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Journal of Fluorescence - published by
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... is an international forum for peer-reviewed original articles that advance the practice of this established spectroscopic technique.
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The excitation wavelength dependence of the steady-state and time-resolved emission spectra of ethyl 5-(4-aminophenyl)-3-amino-2,4-dicyanobenzoate
(EAADCy) in tetrahydrofuran (THF) at room temperature has been examined. It is found that the ratio of the fluorescence intensity
of the long-wavelength and short-wavelength fluorescence bands strongly depends on the excitation wavelength, whereas the
wavelengths of the fluorescence excitation and fluorescence bands maxima are independent on the observation/excitation wavelengths.
The dynamic Stokes shift of fluorophore in locally excited (LE) and intramolecular charge transfer (ICT) states has been studied with a time resolution about 30 ps. The difference between Stokes shift in the LE and ICT states was attributed to the solvent response to the large photoinduced dipole moment of EAADCy in the fluorescent charge
transfer state. On this base we can state that, the relaxation of the polar solvent molecules around the fluorophore was observed.
Content Type Journal Article
DOI 10.1007/s10895-010-0711-4
Authors
Marek Józefowicz, Institute of Experimental Physics, University of Gdańsk, ul. Wita Stwosza 57, 80-952 Gdańsk, Poland
Janina R. Heldt, Institute of Experimental Physics, University of Gdańsk, ul. Wita Stwosza 57, 80-952 Gdańsk, Poland
In this manuscript, we report the fluorescence properties of N-(2-(N’,N’-diethylamino)ethyl)perylene-3,4-dicarboximide (1) and its quaternized derivative N-(2-(N’,N’- diethyl-N’-methylammonium)ethyl)perylene-3,4-dicarboximide tosylate (2) in organic solvents. The effects of carboxylic acids and amines on the fluorescence properties of these compounds were investigated.
In addition, we studied the aggregation and fluorescence properties of (2) and its 9-bromo-substituted derivative (3) in aqueous solution. The fluorescent properties of these compounds change dramatically with the extent of aggregation, thus
allowing these compounds to be used as fluorescent probes for changes in temperature and solvent polarity. For instance, the
fluorescence emission intensity of 3 increases by about 28 times as the temperature of the solution increases from 10°C to 85°C. The fluorescent intensities of
2 and 3 in methanol are higher than that in water by about 8 and 25 times, respectively.
Content Type Journal Article
DOI 10.1007/s10895-010-0708-z
Authors
Liming Huang, Department of Chemistry, University of Nevada, Reno, NV USA
Suk-Wah Tam-Chang, Department of Chemistry, University of Nevada, Reno, NV USA
The metal-ligand complexes, [Ru(bpy)2(dppz)]2+ (bpy = 2,2′-bipyridine, dppz = dipyrido[3,2-a:2′,3′-c]phenazine) (RuBD) and [Ru(phen)2(dppz)]2+ (phen = 1,10-phenanthroline) (RuPD), display favorable photophysical properties including long lifetime, polarized emission,
and very little background fluorescence. To check if RuBD and RuPD reflect the overall rotational mobility of small nucleic
acid, we measured the intensity and anisotropy decays of RuBD and RuPD when intercalated into tRNAtyr using pBC SK(+) phagemid as a control. We used frequency-domain fluorometry with a blue light-emitting diode (LED) as the
modulated light source. We observed shorter lifetimes for tRNAtyr than those for the pBC SK(+) phagemid for both probes, however, RuPD showed much larger decrease in the mean lifetime values
(64%). The slow rotational correlation time of RuBD (31.3 ns) and the fast rotational correlation time of RuPD (26.0 ns) reflected
the overall rotational mobility of tRNAtyr. In addition, the steady-state anisotropy and time-resolved anisotropy decay data showed a clear difference between tRNAtyr and pBC SK(+) phagemid. This suggests the possibility of a homogeneous assay for identifying target nucleic acids and/or
nucleic acid binding proteins.
Content Type Journal Article
DOI 10.1007/s10895-010-0710-5
Authors
Woo Suk Hwang, Department of Oral Biochemistry and Molecular Biology, School of Dentistry, Pusan National University, Yangsan, 626-870 South Korea
Yun Hong Jung, Department of Oral Biochemistry and Molecular Biology, School of Dentistry, Pusan National University, Yangsan, 626-870 South Korea
Woo Sung Son, Department of Orthodontics, School of Dentistry, Pusan National University, Yangsan, 626-870 South Korea
Byeng Wha Son, Department of Chemistry, Pukyong National University, Busan, 608-737 South Korea
Jung Sook Kang, Department of Oral Biochemistry and Molecular Biology, School of Dentistry, Pusan National University, Yangsan, 626-870 South Korea
Novel pyrazolo-pyrrolo-pyrimidine (PPP) derivatives having remarkable photophysical properties are designed with the help
of theoretical semiempirical calculations. These compounds then synthesized successfully and studied effect of substituents
on its photophysical properties.
Figure
Content Type Journal Article
DOI 10.1007/s10895-010-0704-3
Authors
Ramhari V. Rote, Organic Chemistry Research Center, Department of Chemistry, K. T. H. M. College, Gangapur Road, Nashik, 422002 MS India
Deepak P. Shelar, Organic Chemistry Research Center, Department of Chemistry, K. T. H. M. College, Gangapur Road, Nashik, 422002 MS India
Sandeep R. Patil, Organic Chemistry Research Center, Department of Chemistry, K. T. H. M. College, Gangapur Road, Nashik, 422002 MS India
Santosh S. Shinde, Organic Chemistry Research Center, Department of Chemistry, K. T. H. M. College, Gangapur Road, Nashik, 422002 MS India
Raghunath B. Toche, Organic Chemistry Research Center, Department of Chemistry, K. T. H. M. College, Gangapur Road, Nashik, 422002 MS India
Madhukar N. Jachak, Organic Chemistry Research Center, Department of Chemistry, K. T. H. M. College, Gangapur Road, Nashik, 422002 MS India
A new bis(diphenylphosphate)diimine ligand (BP1) was prepared and evaluated for its ability for selective detection of deoxycytidine
5′-monophosphate (dCMP). BP1 exhibited off-type fluorescence in the presence of dCMP. The fluorescence of BP1 was significantly
quenched upon the addition of 2.5 × 10−4 M dCMP and the detection limit was 1.25 × 10−5 M in MeCN-H2O (1:1, v/v). The binding ratio between BP1 and dCMP was determined to be 1:1 with the binding constant of 3.98 ± 0.60 × 10−3 M−1.
Content Type Journal Article
DOI 10.1007/s10895-010-0703-4
Authors
Weerachai Nasomphan, Bioresources Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC) Thailand Science Park, Phaholyothin Road, Klong Luang, Pathumthani 12120, Thailand
Pramuan Tangboriboonrat, Department of Chemistry, Faculty of Science, Mahidol University, Rama 6 Road, Phyathai, Bangkok 10400, Thailand
Srung Smanmoo, Bioresources Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC) Thailand Science Park, Phaholyothin Road, Klong Luang, Pathumthani 12120, Thailand
Two series of phosphors, Na0.5Gd0.5WO4: RE3+ and Na0.5Gd0.5(Mo0.75W0.25)O4: RE3+ (RE = Eu, Sm, Dy) have been synthesized by hydrothermal process to obtain the high purity, which have been characterized
by X-ray powder diffraction (XRD), scanning electron microscope (SEM). The results suggest that Na0.5Gd0.5(Mo0.75W0.25)O4: RE3+ phosphors are more easily to crystallize than Na0.5Gd0.5WO4: RE3+ ones. Both of them present the characteristic luminescence of Eu3+, Sm3+ and Dy3+. Especially the photoluminescent properties of Na0.5Gd0.5WO4: x%Eu3+ (Sm3+) can be obtained to show white luminescence as the suitable doping concentration of Eu3+ or Sm3+.
Content Type Journal Article
DOI 10.1007/s10895-010-0706-1
Authors
Bing Yan, Tongji University Department of Chemistry Shanghai 200092 People’s Republic of China
Lixia Lin, Tongji University Department of Chemistry Shanghai 200092 People’s Republic of China
Jianhua Wu, Tongji University Department of Chemistry Shanghai 200092 People’s Republic of China
Fang Lei, Tongji University Department of Chemistry Shanghai 200092 People’s Republic of China
Using Pb2+ as ion perturber, phenosafranine (PF) and fluorescein isothiocyanate (FITC) could emit strong and stable room temperature
phosphorescence (RTP) signal on the filter paper, respectively. When they were mixed, the phenomenon that the RTP signal of
PF and FITC enhanced significantly was found. And 1.12 ag DNA spot−1 (sample volume was 0.40 μL, corresponding concentration was 2.8 × 10–15 g mL–1) could cause the RTP signal of both PF and FITC to enhance sharply. The content of DNA was proportional to the ΔIp of PF and FITC in the system at 634 and 659 nm. Thus, a new solid substrate room temperature phosphorimetry (SSRTP) for the
determination of trace DNA was established by using FITC-PF as double-luminescent phosphorescence probe. The detection limit
(LD) of this method calculated by 3Sb/k was 14 zg DNA spot–1 for PF and 18 zg DNA spot–1 for FITC, respectively, showing high sensitivity. It has been applied to the determination of trace DNA in practical samples
and the analysis results were in accordance with those of fluorescence probe. The reaction mechanism of SSRTP for the determination
of trace DNA was also discussed.
Content Type Journal Article
DOI 10.1007/s10895-010-0705-2
Authors
Jia-Ming Liu, Zhangzhou Normal College Department of Chemistry and Environmental Science Zhangzhou 363000 People’s Republic of China
Xiao-Mei Huang, Zhangzhou Normal College Department of Chemistry and Environmental Science Zhangzhou 363000 People’s Republic of China
Zhen-Bo Liu, The Third Hospital of Xiamen Xiamen 361100 People’s Republic of China
Fei-Ming Li, Zhangzhou Normal College Department of Chemistry and Environmental Science Zhangzhou 363000 People’s Republic of China
Li-Ping Lin, Zhangzhou Normal College Department of Chemistry and Environmental Science Zhangzhou 363000 People’s Republic of China
Xin-Xing Wang, Zhangzhou Normal College Department of Chemistry and Environmental Science Zhangzhou 363000 People’s Republic of China
Chang-Qing Lin, Zhangzhou Institute of Technology Department of Food and Biological Engineering Zhangzhou 363000 People’s Republic of China
Ya-Hong Huang, Zhangzhou Normal College Department of Chemistry and Environmental Science Zhangzhou 363000 People’s Republic of China
Zhi-Ming Li, Zhangzhou Institute of Technology Department of Food and Biological Engineering Zhangzhou 363000 People’s Republic of China
Shao-Qin Lin, Fujian Education College Department of Biochemistry Fuzhou 350001 China
A novel chromogenic and fluorogenic chemosensor RhB-pMOSal comprising a rhodamine fluorophore and a salicylaldehyde receptor being connected by an iminohydrazine link was synthesized
and fully characterized. Its sensing behavior toward various metal ions in neutral aqueous solution was investigated by absorption
and fluorescence spectroscopy. RhB-pMOSal exhibited a reversible and sensitive “turn-on” response of absorption and fluorescence toward Cu2+ in aqueous acetonitrile solution. Approximate 65 and 6-fold enhancement in the absorbance at 556 nm and fluorescence intensity
at 573 nm were estimated when equivalent Cu2+ was added to the RhB-pMOSal solution. Under the same conditions, RhB-pMOSal displayed more sensitive than a reported analogue RhB-Sal to Cu2+ ion. The competition experiments for Cu2+ mixed with common metal ions exhibited no obvious change in absorption and emission except Cr3+ ion that can induce the fluorescence quenching of RhB-pMOSal to some extent.
Content Type Journal Article
DOI 10.1007/s10895-010-0698-x
Authors
Ruiren Tang, Central South University School of Chemistry and Chemical Engineering Changsha 410083 People’s Republic of China
Kang Lei, Central South University School of Chemistry and Chemical Engineering Changsha 410083 People’s Republic of China
Ke Chen, Central South University School of Chemistry and Chemical Engineering Changsha 410083 People’s Republic of China
Hua Zhao, Product Quality Supervision and Inspection of Yancheng Yancheng 224005 People’s Republic of China
Jingwen Chen, Yancheng Institute of Technology School of Chemical and Biological Engineering Yancheng 224051 People’s Republic of China
This paper reports on the divergent synthesis, photophysical properties and photodegradation of novel PAMAM dendrons, core
and peripherally functionalized with 1,8-naphthalimide fluorophores. The novel compounds were configured as light-harvesting
antennae where the system surface is labeled with blue emitting 4-allyloxy-1,8-naphthalimide “donor” fluorophores capable
of absorbing light and efficiently transferring the energy to a single yellow-green emitting 4-alkylamino-1,8-naphthalimide
“acceptor” dye. The focal 1,8-naphthalimide fluorophores in the antennae were modified with a HALS fragment (2,2,6,6-tetramethylpiperidine
or 1,2,2,6,6-pentamethylpiperidine) with a view to improve their photostability. Novel light-harvesting systems showed highly
efficient energy transfer, depending on the volume of the core substituent. Due to the HALS fragments the chromophoric system
of the novel antennae showed higher photostability, while the photostability of the PAMAM scaffold was found to be lower.
Content Type Journal Article
DOI 10.1007/s10895-010-0689-y
Authors
Nikolai I. Georgiev, University of Chemical Technology and Metallurgy Department of Organic Synthesis Kliment Ohridsky 8 1756 Sofia Bulgaria
Vladimir B. Bojinov, University of Chemical Technology and Metallurgy Department of Organic Synthesis Kliment Ohridsky 8 1756 Sofia Bulgaria
A few new phenoxazine-based conjugated monomers were synthesized, characterized, and successfully used as semiconducting materials.
The phenoxazine-based oligomers have low ionization potentials or high-lying HOMO levels (~4.7 eV), which were estimated from
cyclic voltammetry. Conjugated oligomers offer good film—forming, mechanical and optical properties connected with their wide
application. These results demonstrate that phenoxazine-based conjugated mers are a promising type of semiconducting and luminescent
structures able to be used as thin films in organic electronics.
Content Type Journal Article
DOI 10.1007/s10895-010-0701-6
Authors
Anna Nowakowska-Oleksy, Wrocław University of Technology Faculty of Chemistry Wybrzeże Wyspiańskiego 27 50-370 Wrocław Poland
Jadwiga Sołoducho, Wrocław University of Technology Faculty of Chemistry Wybrzeże Wyspiańskiego 27 50-370 Wrocław Poland
Joanna Cabaj, Wrocław University of Technology Faculty of Chemistry Wybrzeże Wyspiańskiego 27 50-370 Wrocław Poland
The results of our investigation on the sensitized luminescence properties of three Eu(III) β-diketonate complexes of the form [Eu2(fod)6(μ-bpm)], [Eu(fod)3(phen)] and [Eu(fod)3(bpy)] and 4f–4f absorption properties of their Er(III) analogues ( fod = anion of 6,6,7,7,8,8,8- heptafluoro-2,2-dimethyl-3,5-octanedione,
bpm = 2,2′-bipyrimidine, phen = 1,10-phenanthroline and bpy = 2,2′-bipyridyl) in a series of non-aqueous solvents are presented.
The Eu(III) complexes are highly luminescent and their luminescence properties (intensity and band shape) are sensitive to
the changes in the inner coordination sphere of the Eu(III) ion. The luminescence intensity of the mononuclear complexes in
pyridine is drastically decreased. The coordination structure of the complexes in pyridine is transformed into a more symmetrical
one which results into a slow radiative rate of the emission from the complexes. The ancillary ligands, phen and bpy are found
better co-sensitizers as compared to the bpm to sensitize Eu(III)-luminescence. The 4f–4f absorption properties (oscillator strength and band shape) of the Er(III) complexes demonstrate that 4G11/2 ← 4I11/2 and 2H11/2 ← 4I15/2 hypersensitive transitions of Er(III) are very sensitive in some coordinating solvents which reflects complex–solvent interaction
in solution. The hypersensitive transitions of [Er(fod)3(phen)] remain unaffected in any of the solvents and this complex retains its bulk composition in solution. The erbium complexes
as well as the Er(fod)3 chelate are invaded by DMSO. This solvent enters the inner coordination sphere by replacing heterocyclic ligand and the complexes
acquire similar structure [Er(fod)3(DMSO)2] in this solvent. The results reveal that the luminescence and absorption properties of lanthanide complexes in solution
can be controlled by tuning the coordination structure through ancillary ligands and donor solvents. This work shall prove
useful in designing new biological applications with such probes.
Content Type Journal Article
DOI 10.1007/s10895-010-0691-4
Authors
Mir Irfanullah, Jamia Millia Islamia Department of Chemistry New Delhi 110 025 India
Khalid Iftikhar, Jamia Millia Islamia Department of Chemistry New Delhi 110 025 India
Some novel imidazole derivatives were developed for highly sensitive chemisensors for transition metal ions. Since these compounds
are sensitive to different external stimulations such as UV irradiation, heat, increasing pressure and changing the environmental
pH causing colour change and so they can be used as a ′multi-way′ optically switchable material. A prominent fluorescence
enhancement was found in the presence of transition metal ions such as Hg2+, Pb2+ and Cu2+ and this was suggested to result from the suppression of radiationless transitions from the n-π* state in the chemisensors.
The existence of C-H….O intramolecular hydrogen bonding in dmphnpi is confirmed by the Natural Bond Orbital analysis (NBO).
The Mulliken, NBO charge analysis and the HOMO-LUMO energies were also calculated. The electric dipole moment (μ) and the first-hyperpolarisability (β) value of the investigated molecules have been studied both experimentally and theoretically which reveal that the synthesized
molecules have microscopic non-linear optical (NLO) behaviour with non-zero values. Ground and excited state DFT calculation
were carried out in order to find out dipole moment and energy.
Content Type Journal Article
DOI 10.1007/s10895-010-0690-5
Authors
Kanagarathinam Saravanan, Annamalai University Department of Chemistry Annamalainagar 608 002 Tamilnadu India
Natesan Srinivasan, Annamalai University Department of Chemistry Annamalainagar 608 002 Tamilnadu India
Venugopal Thanikachalam, Annamalai University Department of Chemistry Annamalainagar 608 002 Tamilnadu India
Jayaraman Jayabharathi, Annamalai University Department of Chemistry Annamalainagar 608 002 Tamilnadu India
A highly sensitive fluorescent enzyme array for quantitative acetylcholine detection is developed. The enzyme array has been
constructed by spotting of pH sensitive fluorophore 2-phenyl-4-[4-(1,4,7,10-tetraoxa-13-azacycloopentadecyl)benzylidene]oxazol-5-one
and acetylcholinesterase doped in tetraethoxysilane / chitosan matrix via a microarrayer. The constructed tetraethoxysilane
/ chitosan network provided a microenvironment in which the enzyme molecule was active biologically. The optimal operational
conditions for the array developed were investigated. The response of the developed biosensor array to acetylcholine was highly
reproducible (RSD = 3.27%, n = 6). A good linearity was observed for acetylcholine in the concentrations up to 1 × 10−8 M, with a detection limit of 0.27 × 10−8 M.
Content Type Journal Article
DOI 10.1007/s10895-010-0700-7
Authors
Gulsiye Ozturk, University of Dokuz Eylul Faculty of Arts and Sciences, Department of Chemistry Tinaztepe 35160 Izmir Turkey
Karl-Heinz Feller, University of Applied Sciences Jena Department of Medical Engineering and Biotechnology Carl-Zeiss-Promenade 2 07745 Jena Germany
Kay Dornbusch, University of Applied Sciences Jena Department of Medical Engineering and Biotechnology Carl-Zeiss-Promenade 2 07745 Jena Germany
Suna Timur, Ege University Faculty of Science, Department of Biochemistry Bornova 35100 Izmir Turkey
Serap Alp, University of Dokuz Eylul Faculty of Arts and Sciences, Department of Chemistry Tinaztepe 35160 Izmir Turkey
Yavuz Ergun, University of Dokuz Eylul Faculty of Arts and Sciences, Department of Chemistry Tinaztepe 35160 Izmir Turkey
In this paper, we attempted to develop a novel application of Mn-doped ZnSe quantum dots (Mn: ZnSe d-dots) as probes to detect
L-tyrosine (L-Tyr). The bio-conjugates of horseradish peroxidase (HRP)-conjugated Mn: ZnSe d-dots were used in the enzyme
catalyzed reaction of L-Tyr with H2O2. Compared with traditional CdTe QDs, Mn: ZnSe d-dots have better biocompatibility and less negative impact on enzyme catalyzed
system. In HRP-conjugated Mn: ZnSe-L-Tyr-H2O2 system, electron transfer occurred between Mn: ZnSe d-dots and HRP. It resulted in the luminescence quenching of the Mn:
ZnSe d-dots., which can be used to detect L-Tyr. The coupling of efficient quenching of Mn: ZnSe d-dots photoluminescence
(PL) and the effective enzyme-catalysis can afford a simple and sensitive method for L-Tyr detection. The Mn: ZnSe d-dots-enzyme
catalyzed system displays great potential in the development of enzyme-based biosensing systems for various analytes.
Content Type Journal Article
DOI 10.1007/s10895-010-0696-z
Authors
Qiang Ma, Jilin University Department of Analytical Chemistry, College of Chemistry Qianwei Road 10 Changchun Jilin 130012 China
Wei Yu, Jilin University Department of Analytical Chemistry, College of Chemistry Qianwei Road 10 Changchun Jilin 130012 China
Hui Huang, Jilin University Department of Analytical Chemistry, College of Chemistry Qianwei Road 10 Changchun Jilin 130012 China
Xingguang Su, Jilin University Department of Analytical Chemistry, College of Chemistry Qianwei Road 10 Changchun Jilin 130012 China
The photophysical properties of 5-(4-fluorophenyl)-2-hydroxypyridine (FP2HP) have been studied by steady state and time resolved
spectroscopy in combination with quantum chemical calculations. The molecule FP2HP exists as lactim and lactam form in the
ground state due to small stability difference but does not undergo lactim to lactam isomerisation due to high barrier energy.
Whereas in the excited state the lactim form undergoes tautomerization producing red shifted emission of the lactam tautomer
along with the local emission of the lactim form. In polar protic solvents, the barrier for lactim-lactam tautomerization
rapidly decreases forming the lactam tautomer only. Temperature has pronounced effect on the excited state tautomerization
equilibrium and is clearly reflected in the measured equilibrium constant (Ktau0) and free energy change (ΔG0). Structural calculations at Hartree Fock and Density Functional Theory levels, calculated stability of the isomers in different
solvents using Polarized Continuum Model and the theoretical potential energy surfaces for the ground and excited states along
the proton transfer coordinate are reported for the tautomeric equilibrium of FP2HP.
Content Type Journal Article
DOI 10.1007/s10895-010-0692-3
Authors
Anuva Samanta, University of Calcutta Department of Chemistry 92 A. P. C. Road Kolkata 700009 India
Bijan Kumar Paul, University of Calcutta Department of Chemistry 92 A. P. C. Road Kolkata 700009 India
Samiran Kar, University of Calcutta Department of Chemistry 92 A. P. C. Road Kolkata 700009 India
Nikhil Guchhait, University of Calcutta Department of Chemistry 92 A. P. C. Road Kolkata 700009 India
Nanoporous silica gel was employed to extract uranyl from contaminated soil and to enhance the fluorescence intensity and
lifetime. The fluorescence lifetime and intensity of uranyl ions absorbed within nanoporous silica gel was measured from pH 1–13.
The results show that the uranyl fluorescence intensity can be enhanced by approximately two orders of magnitude by the silica
nanoporous matrix from pH 4–12 with the greatest enhancement occurring from pH 4–7. The enhanced fluorescence lifetime can
be used in time-gated measurements to help minimize the influence of background environmental fluorophores.
Content Type Journal Article
DOI 10.1007/s10895-010-0695-0
Authors
Chien-Cheng Chen, Virginia Commonwealth University Department of Mechanical Engineering Richmond VA 23284 USA
Dmitry Pestov, Virginia Commonwealth University Department of Mechanical Engineering Richmond VA 23284 USA
Jean D. Nelson, Topographic Engineering Center US Army Engineer Research and Development Center Alexandria VA 22315 USA
John E. Anderson, Topographic Engineering Center US Army Engineer Research and Development Center Alexandria VA 22315 USA
Gary Tepper, Virginia Commonwealth University Department of Mechanical Engineering Richmond VA 23284 USA
A rapid, simple and highly sensitive first derivative synchronous fluorometric method has been developed for the simultaneous
analysis of binary mixture of sulpiride (SUL) and mebeverine hydrochloride (MEB). The method is based upon measurement of
the synchronous fluorescence intensity of these drugs at ∆λ = 100 nm in water. The different experimental parameters affecting
the fluorescence of the two drugs were carefully studied and optimized. The fluorescence-concentration plots were rectilinear
over the range of 0.05–1 µg/mL and 0.2–3.2 µg/mL for SUL and MEB respectively with lower detection limits (LOD) of 0.006 and
0.01 µg/mL and quantification limits (LOQ) of 0.0.02 and 0.05 µg/mL for SUL and MEB, respectively. The proposed method was
successfully applied for the determination of the two compounds in synthetic mixtures and in commercial tablets. The high
sensitivity attained by the proposed method allowed the determination of both of SUL and MEB metabolite (veratic acid) in
real human plasma samples applying second derivative synchronous fluorometric technique. The mean% recoveries (n = 3) for both MEB metabolite (veratic acid) and SUL were 99.82 ± 2.53 and 98.84 ± 6.20 for spiked human plasma respectively,
while for real human plasma, the mean% recoveries (n = 3) were 91.49 ± 4.25 and 91.36 ± 8.46 respectively.
Content Type Journal Article
DOI 10.1007/s10895-010-0679-0
Authors
M. Walash, University of Mansoura Department of Analytical Chemistry, Faculty of Pharmacy 35516 Mansoura Egypt
M. Sharaf El-Din, University of Mansoura Department of Analytical Chemistry, Faculty of Pharmacy 35516 Mansoura Egypt
Nahed El-Enany, University of Mansoura Department of Analytical Chemistry, Faculty of Pharmacy 35516 Mansoura Egypt
M. Eid, University of Mansoura Department of Analytical Chemistry, Faculty of Pharmacy 35516 Mansoura Egypt
Sh. Shalan, University of Mansoura Department of Analytical Chemistry, Faculty of Pharmacy 35516 Mansoura Egypt
In this paper, we report a novel biological fluorescent probe for the diagnosis of human ovarian tumor based on sandwiched
TiO2 nanoparticles. The fluorescence nanoparticles consist of a fluorescent molecule, tetramethyl rhodamine isothiocyanate (TRITC),
sandwiched between titanium dioxide (TiO2) nanoparticles and nano-gold via reacting with each other. The antibodies HER2, labeled on the surface of the biofluorescence
nanoparticles, have granted nanoparticles the privilege of aiming at peculiar tumor antigen. The specificity of antibody-nanoparticles
interacting with cells was characterized by Laser Scanning Confocal Microscope. The results showed that these sandwiched nanoparticles
were innocuous and stable, and the method offered potential advantages of sensitivity and simplicity due to high combing efficiency
between nanoparticles and cells and provided an alternative method for the diagnosis of human ovarian tumor (HOT).
Content Type Journal Article
DOI 10.1007/s10895-010-0702-5
Authors
Peisi Zhu, Shanghai Normal University College of Life and Environment Shanghai 200234 China
Shasheng Huang, Shanghai Normal University College of Life and Environment Shanghai 200234 China
Mengyao Li, Shanghai Normal University College of Life and Environment Shanghai 200234 China
Na Ding, Shanghai Normal University College of Life and Environment Shanghai 200234 China
Bing Peng, Shanghai Normal University College of Life and Environment Shanghai 200234 China
Lingmi Kong, Shanghai Normal University College of Life and Environment Shanghai 200234 China
Yang Bo, Shanghai Normal University College of Life and Environment Shanghai 200234 China
We found that the fluorescence intensity of the lanthanum (La3+)-curcumin (CU) complex can be highly enhanced by proteins in the presence of sodium dodecyl benzene sulphonate (SDBS). Based
on this finding, a new fluorimetric method for the determination of protein was developed. Under optimized conditions, the
enhanced intensities of fluorescence are quantitatively in proportion to the concentrations of proteins in the range 0.0080–20.0 μg·mL−1 for bovine serum albumin (BSA) and 0.00080–20.0 μg·mL−1 for human serum albumin (HSA) with excitation of 425 nm, and 0.00020–20.0 μg·mL−1 for bovine serum albumin (BSA) and 0.00080–20.0 μg·mL−1for human serum albumin (HSA) with excitation of 280 nm, while corresponding qualitative detection limits (S/N ≥ 3) are as
low as 5.368, 0.573, 0.049, 0.562 µg·mL−1, respectively. Study on reaction mechanism reveals that proteins can bind with La3+, CU and SDBS through self-assembling function with electrostatic attraction, hydrogen bonding, hydrophobic interaction and
van der Waals forces, etc. The proteins form a supermolecular association with multilayer structure, in which La3+-CU is clamped between BSA and SDBS. The unique high fluorescence enhancement of CU is resulted through synergic effects of
favorable hydrophobic microenvironment provided by BSA and SDBS, and efficient intermolecular energy transfer among BSA, SDBS
and CU. In energy transfer process, La3+ plays a crucial role because it not only shortens the distance between SDBS and CU, but also acts as a “bridge” for transferring
the energy from BSA to CU.
Content Type Journal Article
DOI 10.1007/s10895-010-0686-1
Authors
Feng Wang, Zaozhuang University Department of Chemistry Zaozhuang 277160 People’s Republic of China
Wei Huang, Zaozhuang University Department of Chemistry Zaozhuang 277160 People’s Republic of China
Yunfeng Zhang, Zaozhuang University Department of Chemistry Zaozhuang 277160 People’s Republic of China
Mingyin Wang, Zaozhuang University Department of Chemistry Zaozhuang 277160 People’s Republic of China
Lina Sun, Zaozhuang University Department of Chemistry Zaozhuang 277160 People’s Republic of China
Bo Tang, Shandong Normal University College of Chemistry, Chemical Engineering and Materials Science Jinan 250014 People’s Republic of China
Wei Wang, Oak Ridge National Laboratory Environmental Sciences Division Oak Ridge TN 37831-6036 USA
Mg+2 and Cu+2 have different binding capacities to quinolone drugs and have different binding modes with calf thymus DNA. Using the method
of absorption and fluorescence spectroscopy, the influence of Mg+2 and Cu+2 on the binding between calf thymus DNA and each of four quinolone drugs has been studied. The results show that both Mg+2 and Cu+2 can bind with the four drugs. In the absence of divalent metal ions, quinolone drugs interact with DNA double helix by forming
hydrogen bonds between the carboxyl and carbonyl groups of the drugs and the phosphate groups of the DNA bases, and the binding
capacity shows a close relationship with the drug structures. The two metal ions show different influences on the binding
between the drug and DNA, which depends on the type of ion, concentration of the metal ions and the structure of drugs. Mg+2 in lower concentrations (0.01 mM to 3.0 mM) can act as a bridge between the carboxyl group/carbonyl group of the drug and
the phosphate group of the DNA by electrostatic interaction, while Cu+2 can act as an intermediary ion between carboxyl group/carbonyl group of the drug and the DNA bases by a co-ordinate bond.
Both actions can increase the interaction of the π electron between the condensed rings of the drugs and the DNA bases. In
some conditions, Cu+2 can weaken the binding between the drug and the DNA by competitive inhibition if there is a site on the drug that can directly
bind both DNA bases and Cu+2.
Content Type Journal Article
DOI 10.1007/s10895-010-0694-1
Authors
Guo Dong-Sheng, Shanxi University College of Environment and Resources Taiyuan 030006 China
Jing Bo-Yu, Shanxi University College of Environment and Resources Taiyuan 030006 China
Yuan Xiao-Ying, Shanxi University College of Chemistry and Chemical engineering Taiyuan 030006 China
CdSe/CdS quantum dots (QDs) capped with L-cysteine can provide an effective platform for the interactions with bovine serum
albumin (BSA). In this study, absorption and fluorescence (FL) spectroscopy were used to study the binding reactions of QDs
with BSA, respectively. The binding constant (≈104 M-1) from FL quenching method matches well with that determined from the absorption spectral changes. The modified Stern-Volmer
quenching constant (5.23 × 104, 5.22 × 104, and 4.90 × 104 M-1) and the binding sites (≈1) at different temperatures (304 K, 309 K, and 314 K) and corresponding thermodynamic parameters
were calculated (∆G < 0, ∆H < 0, and ∆S < 0). The results show the quenching constant is inversely correlated with temperature. It indicates the quenching mechanism
is the static quenching in nature rather than dynamic quenching. The negative values of free energy (∆G < 0) suggest that the binding process is spontaneous, ∆H < 0 and ∆S < 0 suggest that the binding of QDs to BSA is enthalpy-driven. The enthalpy and entropy changes for the formation of ground
state complex depend on the capping agent of QDs and the protein types. Furthermore, the reaction forces were discussed between
QDs and BSA, and the results show hydrogen bonds and van der Waals interactions play a major role in the binding reaction.
Content Type Journal Article
DOI 10.1007/s10895-010-0685-2
Authors
Ling Ding, Wuhan University College of Resource & Environmental Sciences, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory Wuhan 430079 People’s Republic of China
P. J. Zhou, Wuhan University College of Resource & Environmental Sciences, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory Wuhan 430079 People’s Republic of China
S. Q. Li, Wuhan University College of Resource & Environmental Sciences, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory Wuhan 430079 People’s Republic of China
G. Y. Shi, Wuhan University College of Resource & Environmental Sciences, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory Wuhan 430079 People’s Republic of China
T. Zhong, Wuhan University of Science and Technology College of Chemical Engineering and Technology Wuhan 430081 People’s Republic of China
M. Wu, Wuhan University of Science and Technology College of Chemical Engineering and Technology Wuhan 430081 People’s Republic of China
A sensitive and simple spectrofluorimetric method has been developed and validated for the determination of the antidepressant
paroxetine HCl (PXT) in its dosage forms. The method was based on coupling reaction of PXT with 4-chloro-7-nitrobenzo-2- oxa-1,3-diazole
(NBD-Cl) in an alkaline medium (pH 8) to form a highly fluorescent derivative that was measured at 530 nm after excitation
at 460 nm. The factors affecting the formation and stability of the reaction product were carefully studied and optimized.
The fluorescence–concentration plot is rectilinear over the range 0.2-6 μg/mL with LOD of 0.08 μg/mL and LOQ of 0.24 μg/mL
respectively. The method was applied to the analysis of commercial tablets and the results were in good agreement with those
obtained using the reference method. The mean percentage recoveries for paxetin and xandol tablets were 101.27 ± 1.79 and
101.33 ± 1.19 respectively. A proposal of the reaction pathway was postulated.
Content Type Journal Article
DOI 10.1007/s10895-010-0693-2
Authors
M. Walsh, University of Mansoura Department of Analytical Chemistry, Faculty of Pharmacy Mansoura 35516 Egypt
F. Belal, University of Mansoura Department of Analytical Chemistry, Faculty of Pharmacy Mansoura 35516 Egypt
Nahed El-Enany, University of Mansoura Department of Analytical Chemistry, Faculty of Pharmacy Mansoura 35516 Egypt
H. Elmansi, University of Mansoura Department of Analytical Chemistry, Faculty of Pharmacy Mansoura 35516 Egypt
Two cinnamic acid derivatives (CPA and CPC) containing carbazolyl triphenylethylene moiety have been synthesized and characterized. The two derivatives possessed aggregation-induced
emission property. They exhibited different and interesting responsive behaviors to solvents, water and metal ions. Considering
the structural differences between the two derivatives resulting in different interactions between their molecules and the
various media was proposed as a possible explanation for these observations. The intermolecular interactions of CPC were much stronger than those of CPA, which promoted molecular association through intermolecular hydrogen bonding to form multimers. It was found that CPC and CPA exhibited high sensitivity to K+ and Mn2+, respectively. It is suggested that the derivatives have potential technological applications in chemosensor fields.
Content Type Journal Article
DOI 10.1007/s10895-010-0697-y
Authors
Xi-qi Zhang, Sun Yat-sen University PCFM Lab, DSAPM Lab, FCM Institute, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering Guangzhou 510275 China
Zhen-guo Chi, Sun Yat-sen University PCFM Lab, DSAPM Lab, FCM Institute, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering Guangzhou 510275 China
Bing-jia Xu, Sun Yat-sen University PCFM Lab, DSAPM Lab, FCM Institute, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering Guangzhou 510275 China
Hai-yin Li, Sun Yat-sen University PCFM Lab, DSAPM Lab, FCM Institute, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering Guangzhou 510275 China
Wei Zhou, Sun Yat-sen University PCFM Lab, DSAPM Lab, FCM Institute, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering Guangzhou 510275 China
Xiao-fang Li, Sun Yat-sen University PCFM Lab, DSAPM Lab, FCM Institute, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering Guangzhou 510275 China
Yi Zhang, Sun Yat-sen University PCFM Lab, DSAPM Lab, FCM Institute, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering Guangzhou 510275 China
Si-wei Liu, Sun Yat-sen University PCFM Lab, DSAPM Lab, FCM Institute, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering Guangzhou 510275 China
Jia-rui Xu, Sun Yat-sen University PCFM Lab, DSAPM Lab, FCM Institute, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering Guangzhou 510275 China
This paper describes a new fluorescent family of branched dyes containing benzophenone unit including 4-N, N-diphenylamino-4′-phenacyl-stilbene (C1), 4,4′-di(4-benzoylphenylethylene)yl-triphenylamine (C2) and 4,4′,4″-tri(4-benzoylphenylethylene)yl-triphenylamine (C3). Benzophenone part is coupled with core through C–C double bond. The chemical structures of the derivatives are characterized
with 1H and 13C nuclear magnetic resonance and elemental analysis. Strong π–π stacking interactions are discovered with the analysis of
the X-ray crystallographic data of C1. The absorption maxima and emission maxima of the derivatives exhibit gradual bathochromic shift from C1 to C3. The optical density of C1, C2 and C3 are shown to be related to the number of branches. The changes of dipole moments between the excited and ground states for
C1, C2 and C3 were estimated to be 4.356, 8.091 and 8.479 Derby, respectively by Lippert equation, confirming that the internal charge
transfer (ICT) dominates the process of excited singlet state. The possibility as fluorescence probes of the derivatives on
the estimation of what region of micelles interacting with samples was evaluated.
Content Type Journal Article
DOI 10.1007/s10895-010-0699-9
Authors
Fang Gao, Chongqing University College of Chemistry and Chemical Engineering Chongqing 400044 China
Lanying Niu, Chongqing University College of Chemistry and Chemical Engineering Chongqing 400044 China
Nvdan Hu, Chongqing University College of Chemistry and Chemical Engineering Chongqing 400044 China
Jianchao Wang, Chongqing University College of Chemistry and Chemical Engineering Chongqing 400044 China
Hongru Li, Chongqing University College of Chemistry and Chemical Engineering Chongqing 400044 China
Shengtao Zhang, Chongqing University College of Chemistry and Chemical Engineering Chongqing 400044 China
A simple colorimetric and ratiometric fluorescent anion sensor 1, was rationally designed and synthesized by facile one-step
condensation on basis of the mechanism of intramolecular charge transfer (ICT). The sensor 1 shows more highly and selectively
ability to F− that induced the color changes from little yellow to purple, absorption-transferred to long wavelength and emission-transferred
to short wavelength. Accordingly, 1H NMR analysis reveals that the F−-induced colorimetric and fluorometric responses of 1 are simply driven by hydrogen bonding interaction between the NH protons
and F− ions.
Content Type Journal Article
DOI 10.1007/s10895-010-0681-6
Authors
Yaping Li, Nankai University Department of Chemistry Tianjin 300071 People’s Republic of China
Hai Lin, Nankai University Key Laboratory of Functional Polymer Materials of Ministry of Education Tianjin 300071 People’s Republic of China
Huakuan Lin, Nankai University Department of Chemistry Tianjin 300071 People’s Republic of China
Amyloids are highly organized insoluble protein aggregates that are associated with a large variety of degenerative diseases.
In this work, we investigated the anisotropic architecture of isolated human amyloid samples stained with Congo Red. This
was performed by fluorescence detected linear dichroism (FDLD) imaging in a laser scanning confocal microscope that was equipped
with a differential polarization attachment using high frequency modulation of the polarization state of the laser beam and
a demodulation circuit. Two- and three-dimensional FDLD images of amyloids provided information on the orientation of the
electric transition dipoles of the intercalated Congo Red molecules with unprecedented precision and spatial resolution. We
show that, in accordance with linear dichroism imaging (Jin et al. Proc Natl Acad Sci USA 100:15294, 2003), amyloids exhibit strong anisotropy with preferential orientation of the dye molecules along the fibrils; estimations on
the orientation angle, of around 45°, are given using a model calculation which takes into account the helical organization
of the filaments and fibrils. Our data also show that FDLD images display large inhomogeneities, high local values with alternating
signs and, in some regions, well identifiable µm-sized periodicities. These features of the anisotropic architecture are accounted
for by supercoiling of helically organized amyloid fibrils.
Content Type Journal Article
DOI 10.1007/s10895-010-0684-3
Authors
Gábor Steinbach, Hungarian Academy of Sciences Biological Research Center P.O. Box 521 Szeged 6701 Hungary
István Pomozi, Hungarian Academy of Sciences Biological Research Center P.O. Box 521 Szeged 6701 Hungary
Dávid Péter Jánosa, Hungarian Academy of Sciences Biological Research Center P.O. Box 521 Szeged 6701 Hungary
Josef Makovitzky, University of Heidelberg Department of Neuropathology Heidelberg Germany
Győző Garab, Hungarian Academy of Sciences Biological Research Center P.O. Box 521 Szeged 6701 Hungary
Solid complexes of terbium and europium nitrates with an amino-alkenone type ligand, 1-[2-(6-methylpyridin-2-ylamino)-5,6-dihydro-4H-pyran-3-yl]ethanone
(L) have been prepared and characterized by elemental analysis, conductivity measurements, and IR spectra. The crystal and
molecular structures of the complexes [TbL2(NO3)3(H2O)]·CHCl3 (1) and [EuL2(NO3)3(H2O)]·CH3CO2C2H5 (2) have been determined by single crystal X-ray diffraction. And the coordination spheres of the complexes are similar.
At the same time, the luminescent properties of the Tb3+ complex in solid state and in solvents were investigated at room temperature. Under the excitation of UV light, Tb(III) complex
exhibited characteristic emissions but not for the Eu(III) complex. The lowest triplet state energy level of the ligand in
the complex matches better to the resonance level of Tb(III) than Eu(III) ion.
Content Type Journal Article
DOI 10.1007/s10895-010-0687-0
Authors
Jun Xu, Lanzhou University Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering Lanzhou 730000 People’s Republic of China
Yu-Fei Ma, Lanzhou University Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering Lanzhou 730000 People’s Republic of China
Wei-Sheng Liu, Lanzhou University Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering Lanzhou 730000 People’s Republic of China
Yu Tang, Lanzhou University Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering Lanzhou 730000 People’s Republic of China
Min-Yu Tan, Lanzhou University Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering Lanzhou 730000 People’s Republic of China
In this study we have employed two ionic liquids (ILs) as a new media for the analysis of aluminum in aqueous solutions by
spectrofluorimetric method. ILs are liquid salts and they have no measurable vapor pressure up to their thermal decomposition
point, >300 °C. This lack of vapor pressure makes these materials highly attractive for many studies as they can be used as
clean solvents. Besides they are promising environments for analysis purposes and optical sensor designs. The results revealed
that absorption, excitation and emission spectra of the morin–Al complex exhibited considerable changes in moieties. The morin–Al
complex was stable at aluminum concentrations below 9.1 mg L−1 in 25% 1-butyl-3-methylimidazolium bromide (IL-I)-water binary mixtures. The higher concentrations of IL (>25% by volume)
was not suitable for the complex formation thus in pure IL media the complex formation even at high aluminum concentrations
was not observed. The complex stoichiometry ratio of aluminum:morin was 2:1 in IL-I-water binary mixtures. The linear concentration
range was 0.045–7.2 mg L−1 with a correlation coefficient of r = 0.9909. The detection limit was found to be 0.036 mg L−1. Cu2+, Mn2+ and PO43− ions exhibited less interfering effect in presence of IL-I and the tolerance limit of Cu enhanced 10 times when compared
with ethanol.
Content Type Journal Article
DOI 10.1007/s10895-010-0688-z
Authors
Ozlem Oter, University of Dokuz Eylul Department of Chemistry, Faculty of Arts and Sciences 35160 Buca Izmir Turkey
Sibel Aydogdu, University of Dokuz Eylul Department of Chemistry, Faculty of Arts and Sciences 35160 Buca Izmir Turkey
Spectroscopic studies of the biologically active compound 2-(4-fluorophenylamino)-5-(2,4-dihydroxybenzeno)-1,3,4-thiadiazole
(FABT), have been performed. Absorption studies in the UV-Vis region for FABT in polar solvents, like water or ethanol, exhibit
the domination of the enol form over its keto counterpart, with a broad absorption band centered around 340 nm. In non-polar
solvents such as n-heptane or heavier alkanes the 340 nm absorption band disappears and an increase of the band related to
the keto form (approximately 270 nm) is observed. Fluorescence spectra (with 270 nm and 340 nm excitation energies used) show
a similar dependence: for FABT in 2-propanol a peak at about 400 nm dominates over that at 330 nm while in n-heptane this
relation is reversed. The solvent dependent equilibrium between the keto and enol forms is further confirmed by FTIR and Raman
spectroscopies. As can be expected, this equilibrium also shows some temperature dependences. We note that the changes between
the two tautomeric forms of FABT are not related to the permanent dipole moment of the solvent but rather to its dipole polarizability.
Content Type Journal Article
DOI 10.1007/s10895-010-0682-5
Authors
Mariusz Gagoś, University of Life Sciences in Lublin Department of Biophysics 20-950 Lublin Poland
Arkadiusz Matwijczuk, University of Life Sciences in Lublin Department of Biophysics 20-950 Lublin Poland
Daniel Kamiński, University of Life Sciences in Lublin Department of Chemistry 20-950 Lublin Poland
Andrzej Niewiadomy, University of Life Sciences in Lublin Department of Chemistry 20-950 Lublin Poland
Radosław Kowalski, Central Apparatus Laboratory University of Life Sciences in Lublin Department of Analysis and Evaluation of Food Quality 20-262 Lublin Poland
Grzegorz P. Karwasz, Nicolaus Copernicus University Aleksander Jabłoński Institute of Physics 87100 Toruń Poland
In this study, the interactions of different groups substituted xanthone derivatives with calf thymus DNA (ct DNA) have been
investigated by spectrophotometric methods and viscosity measurements. Results indicate that xanthone derivatives can intercalate
into the DNA base pairs by the plane of xanthone ring and the various substituents may influence the binding affinity with
DNA according to the calculated quenching constant values and the melting temperature of DNA. Furthermore, three tumor cell
lines including esophagus squamous cancer cell line (ECA109), stomach cancer cell line (SGC7901) and lung cancer cell line
(GLC-82) have been used to evaluate the cytotoxic activities of xanthone derivatives by MTT (microculture tetrazolium) method.
Analysis show that the oxiranylmethoxy or piperidinylethoxy substituted xanthones exhibit more effective cytotoxic activity
against three cancer cells than the other substituted xanthones. The effects on the inhibition of tumor cells in vitro agree
with the studies of DNA-binding.
Content Type Journal Article
DOI 10.1007/s10895-010-0680-7
Authors
Rui Shen, Nankai University College of Pharmacy Tianjin 300071 People’s Republic of China
Peng Wang, Nankai University College of Pharmacy Tianjin 300071 People’s Republic of China
Ning Tang, Lanzhou University College of Chemistry and Chemical Engineering Lanzhou 730000 People’s Republic of China
Recently, the graphical analysis of the fluorescence lifetime imaging using the phasor approach has been highlight, and a
series of the reports have made it on the way for the applications by the nonprofessionals. In this paper, we put forward
a similar theory validated by the experiments for the dynamic fluorescence anisotropy imaging. By subtracting the perpendicular
component from the parallel one in the frequency-domain polarization measurement, we deduce a new analytical expression about
the fluorescence joint time, and find that as much as the fluorophore is a single exponential decay and
r¥
is equal to zero, △I(t) is a single exponential decay with the time constant X as well, and the center of its histograms is located on the semicircle in the polarized phasor plot. In the end, we conclude
that the fluorescence joint time is the best parameter to weigh the fluorescence dynamics for the macromolecules.
Content Type Journal Article
DOI 10.1007/s10895-010-0683-4
Authors
Yanzhou Zhou, Guangdong University of Technology Faculty of Automation Guangzhou Guangdong 510006 People’s Republic of China
Long Wu, Guangdong University of Technology Faculty of Automation Guangzhou Guangdong 510006 People’s Republic of China
Qinruo Wang, Guangdong University of Technology Faculty of Automation Guangzhou Guangdong 510006 People’s Republic of China
Yonghua Wang, Guangdong University of Technology Faculty of Automation Guangzhou Guangdong 510006 People’s Republic of China
The fluorescence spectroscopic behavior of three 2-naphthylalanine containing Gonadotropin-releasing hormone (GnRH) antagonists
Cetrorelix, Teverelix and Ozarelix has been investigated concerning their aggregation process in comparison to the non-aggregating
peptide D-Phe6-GnRH. The aim of the present investigation consisted in developing a method to determine the critical aggregation concentration
for these decapeptides. This was achieved by monitoring the incorporation of the fluorescent probe 1-anilino-8-naphthalene
sulfonate (ANS) into aggregates and utilizing the modification of band shape and intensity of the intrinsic peptide fluorescence
emission depending on the analyzed peptide concentrations. Finally an approach for the explanation of the observed band characteristics
is presented analyzing the fluorescence of fragments Cetrorelix1–4 and Cetrorelix1–6.
Content Type Journal Article
DOI 10.1007/s10895-010-0674-5
Authors
Alexander Schneider, Technische Universität Dresden Allgemeine Biochemie Bergstr. 66 01069 Dresden Germany
Alexander Lang, Technische Universität Dresden Allgemeine Biochemie Bergstr. 66 01069 Dresden Germany
Wolfgang Naumann, Technische Universität Dresden Allgemeine Biochemie Bergstr. 66 01069 Dresden Germany
UV-VIS absorption and fluorescence spectroscopic properties of six related polyaromatic 2-pyridones have been studied. Excitation
of the lowest and rather weak and structure-less transition [εmax (430 nm) ≈ 3,000 mol−1dm3cm−1] gives rise to a broad fluorescence band in the visible region, for these compounds. These S0 ↔ S1 transitions are compatible with symmetrically forbidden transitions, promoted by intensity borrowing, as is revealed by fluorescence
depolarisation data. With one exception, all compounds exhibit strong fluorescence, with quantum yields in glycerol varying
between 40% and 70%. The corresponding fluorescence lifetimes range from 11 ns to 17 ns, while the radiative lifetimes are
very similar (≈26 ns), for all compounds. Interestingly and rarely observed, the calculated radiative lifetimes for the weak
absorption band are significantly longer, i.e. between 37 and 40 ns.
Content Type Journal Article
DOI 10.1007/s10895-010-0676-3
Authors
Erik Rosenbaum, Umeå University Department of Chemistry SE-90 187 Umeå Sweden
Magnus Sellstedt, Umeå University Department of Chemistry SE-90 187 Umeå Sweden
Fredrik Almqvist, Umeå University Department of Chemistry SE-90 187 Umeå Sweden
Lennart B.-A. Johansson, Umeå University Department of Chemistry SE-90 187 Umeå Sweden
A key feature of Parkinson’s disease is the formation and accumulation of amyloid fibrils of the natively unfolded protein
α-synuclein (ASN) inside neurons. Recently we have proposed novel sensitive monomethinecyanine dye T-284 as fluorescent probe
for quantitative detection of ASN amyloid fibrils. In this study the T-284 dye complex with ASN fibril was characterized by
means of fluorescence anisotropy, atomic force microscopy and time-resolved fluorescence techniques to give further insights
into the mode of dye interaction with amyloid fibrils. The fluorescence anisotropy of T-284 was shown to noticeably increase
upon addition of aggregated proteins indicating on stable dye/amyloid fibril complex formation. AFM imaging of fibrillar wild-type
ASN revealed differences in heights between ASN fibrils alone and in presence of the T-284 dye (6.37 ± 1.0 nm and 8.0 ± 1.1 nm
respectively), that is believed to be caused by embedding of T-284 dye molecules in the “binding channel” running along the
fibril. Fluorescence decay analysis of the T-284 in complexes with fibrillar ASN variants revealed the fluorescence lifetime
values for T-284/fibril complexes to be an order of magnitude higher as compared to the free dye. Also, the fluorescence decay
of free T-284 was bi-exponential, while dye bound to protein yields tri-exponential decay. We suppose that in complexes with
fibrillar ASN variants T-284 dye might exist in different “populations” due to interaction with fibrils in different conformers
and ways. The exact binding mode of T-284 with ASN fibrils needs further studies. Studied parameters of dye/amyloid fibril
complexes are important for the characterization and screening of newly-developed amyloid-sensitive dyes.
Content Type Journal Article
DOI 10.1007/s10895-010-0678-1
Authors
Kateryna D. Volkova, Institute of Molecular Biology and Genetics of the National Academy of Sciences of Ukraine Department of Combinatorial Chemistry 150 Zabolotnogo St. 03143 Kyiv Ukraine
Vladyslava B. Kovalska, Institute of Molecular Biology and Genetics of the National Academy of Sciences of Ukraine Department of Combinatorial Chemistry 150 Zabolotnogo St. 03143 Kyiv Ukraine
Mykhaylo Yu. Losytskyy, Institute of Molecular Biology and Genetics of the National Academy of Sciences of Ukraine Department of Combinatorial Chemistry 150 Zabolotnogo St. 03143 Kyiv Ukraine
Gertjan Veldhuis, University of Twente MESA + Institute for Nanotechnology, Biophysical Engineering Group Enschede The Netherlands
G. M. J. Segers-Nolten, University of Twente MESA + Institute for Nanotechnology, Biophysical Engineering Group Enschede The Netherlands
Olexiy I. Tolmachev, Institute of Organic Chemistry of the National Academy of Sciences of Ukraine 5 Murmans’ka St. 02094 Kyiv Ukraine
Vinod Subramaniam, University of Twente MESA + Institute for Nanotechnology, Biophysical Engineering Group Enschede The Netherlands
Sergiy M. Yarmoluk, Institute of Molecular Biology and Genetics of the National Academy of Sciences of Ukraine Department of Combinatorial Chemistry 150 Zabolotnogo St. 03143 Kyiv Ukraine
New ethynylated triphenylamine boronic acid sensors 1 and 2 were designed and the photophysical properties, as well as the binding with tartaric acid and mandelic acid were studied.
We found the emission intensity of the sensors is sensitive to the polarity of the solvents and the emission of sensor 2 is sensitive to protic solvents. Theoretical calculations on the low-lying excited states of these sensors predicted d-PET
effect. Experimental observations show either a-PET effect or no significant PET effect for the sensors. The sensitivity of
the emission of the sensors toward solvent polarity is used to rationalize the observed emission intensity-pH profiles.
Content Type Journal Article
DOI 10.1007/s10895-010-0677-2
Authors
Lina Chi, Dalian University of Technology State Key Laboratory of Fine Chemicals, School of Chemical Engineering Dalian 116012 People’s Republic of China
Yubo Wu, Dalian University of Technology State Key Laboratory of Fine Chemicals, School of Chemical Engineering Dalian 116012 People’s Republic of China
Xin Zhang, Dalian University of Technology State Key Laboratory of Fine Chemicals, School of Chemical Engineering Dalian 116012 People’s Republic of China
Shaomin Ji, Dalian University of Technology State Key Laboratory of Fine Chemicals, School of Chemical Engineering Dalian 116012 People’s Republic of China
Jingyin Shao, Dalian University of Technology State Key Laboratory of Fine Chemicals, School of Chemical Engineering Dalian 116012 People’s Republic of China
Huimin Guo, Dalian University of Technology Department of Chemistry, School of Chemical Engineering Dalian 116012 People’s Republic of China
Xin Wang, Sichuan University Faculty of Chemistry Chengdu 610064 People’s Republic of China
Jianzhang Zhao, Dalian University of Technology State Key Laboratory of Fine Chemicals, School of Chemical Engineering Dalian 116012 People’s Republic of China
The molecular recognition properties of p-tert-butyl-calix(8)arene with 1,5 -diamino anthraquinone (1,5 DAAQ) were studied by using UV–Visible and Fluorescence spectroscopic
techniques. The binding constant was determined by using the Benesi-Hilde brand expression. It was found that the host–guest
complex was formed between 1,5 DAAQ and p-tert-butyl- calix(8)arene in the 1:2 Stoichiometry ratio.
Content Type Journal Article
DOI 10.1007/s10895-010-0651-z
Authors
G. Suganthi, Madurai Kamaraj University Department of Laser Studies, School of Physics Madurai 625 021 India
C. Meenakshi, Sri Meenakshi Government College for Women, (Autonomous) Department of Chemistry Madurai 625 002 India
V. Ramakrishnan, Madurai Kamaraj University Department of Laser Studies, School of Physics Madurai 625 021 India
Renal cell carcinoma (RCC) remains one of the greatest challenges of urological oncology and is the third leading cause of
death in genitourinary cancers. RCCs are highly vascularized and are amenable to antiangiogenic therapy. Endostatin (ES) is
a fragment of collagen XVIII that possesses antiangiogenic activity. In this study, we examined the potential of erythrocyte
PpIX fluorescence spectroscopy for monitoring the efficacy of antiangiogenic therapy in metastatic renal cell carcinoma (mRCC),
using an orthotopic metastatic mouse model. Balb/C-bearing Renca cells were treated with NIH/3T3-LendSN cells. Lung weight,
nodule area, microvascular area (MVA), and erythrocyte PpIX fluorescence were evaluated. Emission spectra were obtained by
exciting the samples at 405 nm. There was a significant decrease in lung wet weight, lung nodule area and MVA in the treated
group compared to the control group (P < 0.001). Significant differences in autofluorescence shape were observed in the 620–650 nm spectral region. The most intense
fluorescence peak was observed at ∼632 nm. The autofluorescence of the control samples was about 53% higher than that of normal
blood (P < 0.05). In the group treated with ES, the autofluorescence was about 54% lower than in the control group (P < 0.05). Fluorescence intensity was positively correlated with the nodule area (R2 = 0.8859; P < 0.001) and MVA (R2 = 0.9431; P < 0.001) in the ES-treated group. These results demonstrate that the spectroscopic analysis method allows a selective detection
of tumor masses. This preliminary study suggests that PpIX fluorescence may be useful as a biomarker for antiangiogenic cancer
therapy.
Content Type Journal Article
DOI 10.1007/s10895-010-0672-7
Authors
Flávia Gomes de Góes Rocha, IPEN/CNEN-SP Centro de Biotecnologia São Paulo SP Brazil
Karen Cristina Barbosa Chaves, IPEN/CNEN-SP Centro de Biotecnologia São Paulo SP Brazil
Cinthia Zanini Gomes, IPEN/CNEN-SP Centro de Biotecnologia São Paulo SP Brazil
Camila Barricheli Campanharo, UNIFESP Disciplina de Nefrologia, Departamento de Medicina São Paulo SP Brazil
Lilia Coronato Courrol, UNIFESP Departamento de Ciências Exatas e da Terra São Paulo SP Brazil
Nestor Schor, UNIFESP Disciplina de Nefrologia, Departamento de Medicina São Paulo SP Brazil
Maria Helena Bellini, IPEN/CNEN-SP Centro de Biotecnologia São Paulo SP Brazil
Steady-state absorption, fluorescence excitation and emission spectra of 4-(N,N-dimethylamino)benzonitrile (DMABN) have been measured at room temperature in cyclohexane, 1,4-dioxane, dichloromethane, and
acetonitrile solutions. The fluorescence spectra of DMABN are found to exhibit dual emission in 1,4-dioxane, dichloromethane,
and acetonitrile solutions and single emission in cyclohexane solution. The effect of solvent polarity and excitation wavelength
on the emission spectra has also been studied. The fluorescence excitation spectra of DMABN monitored at the emission bands
are different. The presence of two different conformations of the same molecule in the ground state has lead to two close
lying excited states; local excited (LE) and charge transfer (CT), and thereby results in the dual fluorescence of the compound.
The experimental studies were supported by ab initio density functional theory (DFT) calculations performed at the B3LYP/6-31Gd
level of theory. On the basis of the experimental results and our theoretical calculations, we suggest that there are two
conformers of DMABN, which are stable in the ground state, equilibrated in solution at room temperature that give rise dual
fluorescence upon excitation.
Content Type Journal Article
DOI 10.1007/s10895-010-0675-4
Authors
Tesfay Atsbeha, Addis Ababa University Department of Chemistry P .O. Box 1176 Addis Ababa Ethiopia
Ahmed M. Mohammed, Addis Ababa University Department of Chemistry P .O. Box 1176 Addis Ababa Ethiopia
Mesfin Redi-Abshiro, Addis Ababa University Department of Chemistry P .O. Box 1176 Addis Ababa Ethiopia
Probe 1 was designed and synthesized as a new fluorescent molecular probe for thiols in PBS buffer at physiological condition. This
fluorescent molecular probe consists of a thiol reaction moiety bound to a coumarin fluorophore. Its fluorescence quantum
yield is low, but a drastic enhancement of fluorescence intensity was observed in the presence of thiols. Possible interference
with other analytes was examined. Probe 1 displays a highly selective fluorescent enhancement with thiols, and the probe was successfully applied to thiols determination
in intracellular, in human urine and blood samples.
Content Type Journal Article
DOI 10.1007/s10895-010-0673-6
Authors
Qing-Ping Zuo, Central South University Pharmaceutics Department, College of pharmacy Changsha Hunan 410013 People’s Republic of China
Bing Li, Central South University Department of Pharmacy, The Third Xiangya Hospital Changsha Hunan 410013 People’s Republic of China
Qi Pei, Central South University Department of Pharmacy, The Third Xiangya Hospital Changsha Hunan 410013 People’s Republic of China
Zuojun Li, Central South University Department of Pharmacy, The Third Xiangya Hospital Changsha Hunan 410013 People’s Republic of China
Shi-Kun Liu, Central South University Department of Pharmacy, The Third Xiangya Hospital Changsha Hunan 410013 People’s Republic of China
The absorption and fluorescence spectra of imipramine and carbamazepine have been recorded in solvents of different polarity
and β-cyclodextrin (β-CD). The inclusion complexes for both drugs are investigated by UV-visible, fluorimetry and DFT. Solvents
study shows isotropic polarizability structure is present in imipramine while the amide group inhibits the above structure
in carbamazepine. The band width half a maximum of carbamazepine decreased in polar solvents suggest that different species
present in non-polar solvents and among that one of this species is affected in protic solvents. Both drugs form two different
1:2 inclusion complexes with β-CD. The structured longer wavelength emission in β-CD solution suggests viscosity plays major
roles in the inclusion complex. This study also confirms van der Waals forces and hydrophobic interactions are the driving
forces in imipramine and hydrogen bonding interactions play major roles in carbamazepine.
Content Type Journal Article
DOI 10.1007/s10895-010-0669-2
Authors
A. Antony Muthu Prabhu, Annamalai University Department of Chemistry Annamalai nagar 608 002 Tamilnadu India
G. Venkatesh, Annamalai University Department of Chemistry Annamalai nagar 608 002 Tamilnadu India
N. Rajendiran, Annamalai University Department of Chemistry Annamalai nagar 608 002 Tamilnadu India
Up-converting NaRF4-NaR′F4 (R: Y, Yb, Er) nanomaterials with different core-shell combinations were prepared with the co-precipitation method. The X-ray
powder diffraction (XPD) measurements revealed the presence of both the cubic and hexagonal NaRF4 phases. The crystallite sizes calculated with the Scherrer formula were 100 and 150 nm for the cubic and hexagonal phases,
respectively. The FT-IR spectra showed water impurities. The up-conversion luminescence and luminescence decays were studied
with NIR laser excitation at 970 nm. The up-conversion luminescence spectra showed strong red (640–685 nm) (4F9/2 → 4I15/2) and moderate green (515–560 nm) (2H11/2,4S3/2 → 4I15/2) Er3+ luminescence. The strongest up-conversion luminescence and longest red luminescence decay was obtained from the Na(Y,Yb)F4-NaErF4 core-shell combination.
Content Type Journal Article
DOI 10.1007/s10895-010-0655-8
Authors
Iko Hyppänen, University of Turku Department of Chemistry FI-20014 Turku Finland
Jorma Hölsä, University of Turku Department of Chemistry FI-20014 Turku Finland
Jouko Kankare, University of Turku Department of Chemistry FI-20014 Turku Finland
Mika Lastusaari, University of Turku Department of Chemistry FI-20014 Turku Finland
Laura Pihlgren, University of Turku Department of Chemistry FI-20014 Turku Finland
Tero Soukka, University of Turku Department of Biotechnology FI-20520 Turku Finland
In this work, a SiO2 spherical were prepared by the Stöber Method and then recovered with a single layer of Eu2O3 oxide (SiO2@Eu2O3) obtained by the Polymeric Precursor Method. The SiO2@Eu2O3 powder was heated treated at 100, 300, 400, 500 and 800 °C. The samples were characterized by the Scanning Electonic Microscopy
(SEM), Thermal Analysis (TGA/DTA), and the luminescent properties of the SiO2@Eu2O3 powders were studied by their emission and excitation spectra as well as by the lifetime measurements of the Eu3+5D0 → 7F2 transition. The SEM analysis shows that the silica prepared by the Stöber Method is spherical with a particle size of 460 nm.
The emission spectra of the SiO2@Eu2O3 powders presented the Eu3+ characteristics bands related to the 5D0 → 7FJ (J = 0, 1, 2, 3, 4) transitions at 577, 591, 616, 649 and 695 nm, respectively. The band related to the 5D0 → 7F2 transition is the most intense in the spectra, and its intensity decreases with the temperature enhancement. The decay curves
of the SiO2@Eu2O3 samples presented monoexponential features, and the obtained lifetime values were higher than the Eu2O3 oxide. It was possible to conclude that the 5D0 → 7F2 hypersensitive transition is strongly dependent on the Eu3+ surrounding.
Content Type Journal Article
DOI 10.1007/s10895-010-0671-8
Authors
Ieda L. V. Rosa, LIEC-UFSCar Department of Chemistry Caixa Postal 676 13560-905 São Carlos SP Brazil
Larissa H. Oliveira, LIEC-UFSCar Department of Chemistry Caixa Postal 676 13560-905 São Carlos SP Brazil
Elson Longo, LIEC-UNESP, Institute of Chemistry Caixa Postal 355 14801-970 Araraquara SP Brazil
José A. Varela, LIEC-UNESP, Institute of Chemistry Caixa Postal 355 14801-970 Araraquara SP Brazil
The solvatochromic behavior of the 1,4-bis(((2-methylthio) phenylimino)methyl) benzene [BMTPMB] in single solvents and binary
mixtures were investigated. Fluorescence spectra show the dual emission due to twisted intramolecular charge transfer (TICT)
state. The preferential solvation parameters: local mole fraction, X2L, solvation index δs2, exchange constant K12 were calculated for the binary mixtures, ACN+MEOH, DMSO+CCl4 and CCl4+1,2 DCE. The dipole moment ratios between ground and excited states were deduced using the solvatochromic shifts of absorption
and fluorescence spectra as a function of dielectric constant (ε), refractive index (n) and it was found to be 1.25.
Content Type Journal Article
DOI 10.1007/s10895-010-0666-5
Authors
G. Suganthi, Madurai Kamaraj University Department of Laser Studies, School of Physics Madurai 625 021 India
S. Sivakolunthu, Madurai Kamaraj University Department of Inorganic Chemistry, School of Chemistry Madurai 625 021 India
V. Ramakrishnan, Madurai Kamaraj University Department of Laser Studies, School of Physics Madurai 625 021 India
An approach is demonstrated toward the synthesis of four novel cyclohexenone derivatives (CDs) via a convenient route of Michael addition of ethyl acetoacetate. The molecular structures of CDs were confirmed by means of
FT-IR, 1H NMR, EIMS, UV and also by X-ray single crystal structure analysis. CDs are strongly fluorescent compounds and their fluorescent
spectra exhibits intense violet fluorescence. To model the binding to biological membranes the behavior of CDs in micellar
solutions of a cationic surfactant, cetyltrimethylammonium bromide (CTAB) and an anionic surfactant, sodium dodecylsulfate
(SDS) has also been examined. The characteristics of partition and binding interactions of CDs with CTAB and SDS were investigated
by UV-Visible and fluorescence spectroscopic techniques. Higher values of all mentioned interactions in case of CTAB, compared
to SDS, indicate that there are greater interactions between the CDs and CTAB than with SDS.
Content Type Journal Article
DOI 10.1007/s10895-010-0657-6
Authors
Amir Badshah, Quaid-i-Azam University Department of Chemistry 45320 Islamabad Pakistan
Saleem Nawaz, Quaid-i-Azam University Department of Chemistry 45320 Islamabad Pakistan
Muhammad Faizan Nazar, Quaid-i-Azam University Department of Chemistry 45320 Islamabad Pakistan
Syed Sakhawat Shah, Quaid-i-Azam University Department of Chemistry 45320 Islamabad Pakistan
Aurangzeb Hasan, Quaid-i-Azam University Department of Chemistry 45320 Islamabad Pakistan
A novel high-throughput screening method is described in which a family of DNA aptamers selected against E. coli outer membrane proteins (OMPs) is subjected to PCR in the presence of fluorophore-dUTP conjugates using Deep Vent® exo- polymerase.
The fluorophore-doped aptamers and their complementary strands are then heated to render them single-stranded and screened
in filter well microtiter plates for fluorescence resonance energy transfer (FRET) assay potential. Using this system, a superior
competitive FRET-aptamer designated EcO 4R was identified and the location of its putative binding pocket was determined by
individually testing FRET potential in each of the secondary loop structures. By labeling the binding pocket with Alexa Fluor
(AF) 647 and binding the aptamer to heavily Black Hole Quencher-3 (BHQ-3)-labeled E. coli bacteria, detection of as few as 30 live unlabeled E. coli per ml was achieved in a competitive displacement FRET assay format. The far red fluorescence emission enables detection
in largely blue-green autofluorescent matrices. In addition, the competitive transfer of AF 647-EcO-4R aptamer to unlabeled
E. coli cells after a 15 min equilibration period was verified by fluorescence microscopy. The present study also demonstrated that
high aptamer affinity is not well correlated with competitive FRET potential.
Content Type Journal Article
DOI 10.1007/s10895-010-0670-9
Authors
John G. Bruno, Operational Technologies Corporation 4100 NW Loop 410, Suite 230 San Antonio TX 78229 USA
Maria P. Carrillo, Operational Technologies Corporation 4100 NW Loop 410, Suite 230 San Antonio TX 78229 USA
Taylor Phillips, Operational Technologies Corporation 4100 NW Loop 410, Suite 230 San Antonio TX 78229 USA
Carrie J. Andrews, Operational Technologies Corporation 4100 NW Loop 410, Suite 230 San Antonio TX 78229 USA
Fluorescence anisotropy measurements were performed on a set of multichromophoric compounds, which contain a different number
of aminopyrenyl moieties linked to a triazine ring, in order to reveal the nature of both the electronic excited states and
relaxation pathways of the compounds. Our experimental results complement quantum chemical calculations. We propose that the
lowest excited state from which fluorescence proceeds is localized on a single individual aminopyrene moiety. In contrast,
excitation to a higher excited state is likely followed by a migration of energy to another nearby aminopyrene chromophore
before the internal conversion to the emitting state takes place. We suggest that this migration is responsible for the experimentally
measured decrease of fluorescence anisotropy of the studied compounds.
Content Type Journal Article
DOI 10.1007/s10895-010-0668-3
Authors
Miroslav Dvořák, Czech Technical University in Prague Department of Physical Electronics, Faculty of Nuclear Sciences and Physical Engineering V Holešovičkách 2 180 00 Praha 8 Czech Republic
Martin Michl, Czech Technical University in Prague Department of Physical Electronics, Faculty of Nuclear Sciences and Physical Engineering V Holešovičkách 2 180 00 Praha 8 Czech Republic
Numan Almonasy, University of Pardubice Institute of Organic Chemistry and Technology, Faculty of Chemical Technology Studentská 95 532 10 Pardubice Czech Republic
Miloš Nepraš, University of Pardubice Institute of Organic Chemistry and Technology, Faculty of Chemical Technology Studentská 95 532 10 Pardubice Czech Republic
Nemiah Ladd, Czech Technical University in Prague Department of Natural Sciences, Faculty of Biomedical Engineering Sítná sq. 3105 272 01 Kladno 2 Czech Republic
Vlastimil Fidler, Czech Technical University in Prague Department of Natural Sciences, Faculty of Biomedical Engineering Sítná sq. 3105 272 01 Kladno 2 Czech Republic
Novel light-emitting organic materials comprising conjugated oligomers chemically attached via a flexible spacer to an electron–or hole-conducting core were synthesized by Stille cross-coupling methodology and designed for tunable charge injection and optical properties. The hyperbranched structures
have been characterized by 1H NMR, 13C NMR, and UV-VIS spectroscopy. The obtained structures show good stability in common organic solvents such as CHCl3, toluene, and CH2Cl2 and exhibit excellent thermal stability. A preliminary electroluminescence properties were also investigated. This class
of materials will help to balance charge injection and transport and to spread out the charge recombination zone, thereby
significantly improving the device efficiency and lifetime of unpolarized and polarized OLEDs.
Content Type Journal Article
DOI 10.1007/s10895-010-0659-4
Authors
Krzysztof Idzik, Wrocław University of Technology Department of Chemistry Wybrzeże Wyspiańskiego 27 Wrocław 50-370 Poland
Jadwiga Sołoducho, Wrocław University of Technology Department of Chemistry Wybrzeże Wyspiańskiego 27 Wrocław 50-370 Poland
Mieczysław Łapkowski, Silesian University of Technology Department of Chemistry Strzody 9 Gliwice 44-100 Poland
Przemysław Data, Silesian University of Technology Department of Chemistry Strzody 9 Gliwice 44-100 Poland
A simple, rapid, sensitive and selective method for simultaneously determining xanthopterin and isoxanthopterin content in
human urine has been developed using synchronous fluorescence spectroscopy based on their intrinsic fluorescence. The synchronous
fluorescence spectra were obtained with Δλ = 65 nm in a pH 8.5 KH2PO4-NaOH buffer solution. The detected wavelengths of quantitative analysis were set at 410 nm for xanthopterin and 325 nm for
isoxanthopterin, respectively. Pretreatment of urine samples only was filtrated through a 0.45 μm membrane filter, which was
free from the tedious separation procedures. Under optimized conditions, the limits of detection (LOD) were 0.94 ng/mL for
xanthopterin and 0.48 ng/mL for isoxanthopterin. The recoveries ranged from 88.0% to 103.8 % for healthy and cancer urine
samples, with coefficient of variation between 2.09% and 7.06%. The proposed method has been successfully applied to the simultaneous
analysis for xanthopterin and isoxanthopterin in human urine. The results showed that the average level of isoxanthopterin
was significantly elevated in urine excreted by stomach cancer patients (P < 0.01), while no significant change of xanthopterin level was found between stomach cancer patients and healthy individuals.
This potentially indicates that an increase in amounts of isoxanthopterin can be associated with the presence of stomach cancer.
Content Type Journal Article
DOI 10.1007/s10895-010-0667-4
Authors
Yi-Qun Wan, Nanchang University State key Laboratory of Food Science and Technology Nanchang Jiangxi 330047 People’s Republic of China
Li-Juan Tang, Nanchang University Center of Analysis and Testing Nanchang Jiangxi 330047 People’s Republic of China
Ting Tan, Nanchang University Center of Analysis and Testing Nanchang Jiangxi 330047 People’s Republic of China
Prostate cancer is one of the most common types of cancer in men, and unfortunately many prostate tumours remain asymptomatic
until they reach advanced stages. Diagnosis is typically performed through Prostate-Specific Antigen (PSA) quantification,
Digital Rectal Examination (DRE) and Transrectal Ultrasonography (TU). The antigen (PSA) is secreted by all prostatic epithelial
cells and not exclusively by cancerous ones, so its concentration also increases in the presence of other prostatic diseases.
DRE and TU are not reliable for early detection, when histological analysis of prostate tissue obtained from a biopsy is necessary.
In this context, fluorescence techniques are very important for the diagnosis of cancer. In this paper we explore the potential
of using endogenous phorphyrin blood fluorescence as tumour marker for prostate cancer. Substances such as porphyrin derivatives
accumulate substantially more in tumours than in normal tissues; thus, measuring blood porphyrin concentration by autofluorescence
intensity may provide a good parameter for determining tumour stage. In this study, the autofluorescence of blood porphyrin
was analyzed using fluorescence and excitation spectroscopy on healthy male NUDE mice and in those with prostate cancer induced
by inoculation of DU145 cells. A significant contrast between the blood of normal and cancer subjects could be established.
Blood porphyrin fluorophore showed an enhancement on the fluorescence band around 632 nm following tumour growth. Fluorescence
detection has advantages over other light-based investigation methods: high sensitivity, high speed and safety. However it
does carry the drawback of low specificity of detection. The extraction of blood porphyrin using acetone can solve this problem,
since optical excitation of further molecular species can be excluded, and light scattering from blood samples is negligible.
Content Type Journal Article
DOI 10.1007/s10895-010-0662-9
Authors
Flávia Rodrigues de Oliveira Silva, UNIFESP Departamento de Nefrologia São Paulo SP Brazil
Maria Helena Bellini, UNIFESP Departamento de Nefrologia São Paulo SP Brazil
Vivian Regina Tristão, UNIFESP Departamento de Nefrologia São Paulo SP Brazil
Nestor Schor, UNIFESP Departamento de Nefrologia São Paulo SP Brazil
Nilson Dias Vieira, IPEN/CNEN-SP Centro de Lasers e Aplicações São Paulo SP Brazil
Lilia Coronato Courrol, UNIFESP Departamento de Nefrologia São Paulo SP Brazil
The fluorescence quenching of 5, 6-benzo-4-azidomethyl coumarin (5BAMC) by aniline have been carried in different solvent
mixtures of benzene (BN) and acetonitrile (AN) at room temperature by steady state fluorescence measurements. The quenching
is found to be appreciable and a positive deviation from linearity was observed in the Stern-Volmer plot for the fluorophore
in all the solvent mixtures. Various parameters for the quenching process have been determined using the extended S-V equation
and have been found to be dependent on the solvent polarity. Further, with the use of finite sink approximation model, it
is concluded that the bimolecular reactions quenching reactions are diffusion limited, and the distance parameter R′ and mutual
diffusion coefficient D are estimated independently.
Content Type Journal Article
DOI 10.1007/s10895-010-0664-7
Authors
Raveendra M. Melavanki, M S Ramaiah Institute of Technology Department of Physics Bangalore 560054 Karnataka India
Raviraj A. Kusanur, Karnatak University Department of Chemistry Dharwad 580003 Karnataka India
Jagadish S. Kadadevaramath, Karnatak University Department of Physics Dharwad 580003 Karnataka India
Manohar V. Kulkarni, Karnatak University Department of Chemistry Dharwad 580003 Karnataka India
