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1.
Anal Biochem ; 598: 113690, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32259511

RESUMO

A newly synthesized compound, 5-methyl-1-phenyl-1H-1,2,3-triazole-4- carboxylic acid (MPC) was analyzed for its quantum chemical parameters and theoretical spectrum by computational chemistry. The calculated spectrum was in accord with the experimental measurements in a great degree. Then MPC was successfully designed and synthesized to a novel rhodamine B derivative RMPC. The RMPC exhibited about a 4000-fold increase in fluorescence intensity in the presence of Hg2+ ions over most other competitive metal ions. The triazole appended colorless chemodosimeter RMPC turns to pink upon the complex formation only with Hg2+ ions as a 1: 2 M ratio and enables naked-eye detection. The coordination mechanism of turning on/off fluorescence for Hg2+ ions were well proposed by explaining Hg2+ inducing the ring-opened rhodamine B moiety. The fluorescence imaging experiments of Hg2+ in HeLa cell demonstrated that the probe was labeled and it could be used in biological systems.


Assuntos
Corantes Fluorescentes/química , Mercúrio/análise , Rodaminas/química , Triazóis/química , Teoria da Densidade Funcional , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Íons/análise , Estrutura Molecular , Imagem Óptica
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1191-6, 2016 Apr.
Artigo em Zh | MEDLINE | ID: mdl-30052345

RESUMO

Fourier transform infrared spectroscopy (FT-IR), UV spectroscopy and fluorescence spectroscopy combined with inductively coupled plasma mass spectrometry (ICP-MS) were employed to analyze Alpinia Katsumadai harvested from Hainan Baisha and Bawangling. The results from FT-IR indicated that the emergence of several characteristic absorption peaks around 1 051, 1 390,2 976 and 3 300 cm-1 belong to flavonoids. In light of second derivative spectra, two similar peaks around 2 977.72 and 2 899.94 cm-1 and evident differences peaks around 1 922.36 and 1 650.87 cm-1 were observed, which was obvious to identify and distinguish Hainan Alpinia Katsumadai from different geographical regions. The method of UV spectroscopy were used to determine the different characteristic spectra of Alpinia Katsumadai harvested from Hainan Baisha and Bawangling. An UV-quantitative analysis method for alpinetin and cardamonin in Alpinia Katsumadai was established according to the relevant absorption principle. The results from fluorescence experiments revealed that both ethanol extracts of Alpinia katsumadai Hayata harvestd from Baisha and Bawangling have the similar fluorescence emission spectra and excitation spectra. The difference of fluorescence intensity once again demonstrated the concentration of ethanol extracts of Alpinia katsumadai Hayata harvestd from Baisha was bigger than that of Bawangling. The good relative recovery was in the range of 84.28%~117.41% with the RSDs (n=3) of 0.42%~0.29%. The content of alpinetin and cardamomin in Alpinia katsumadai from various habitats are 4.23% and 3.83% for Baisha, 3.72% and 3.34% for Baiwangling, respectively. Seventeen kinds of metal elements including K, Ca, Mg, Na, Al,Fe, Mn, Cu, Zn et al were determined by using microwave digestion-ICP-MS. Therefore, FT-IR combined with second derivative spectra was an express and comprehensive to analyze and evaluate the subtle difference among different habitats. It was also indicated that the method of UV-absorption spectroscopy was simple and reliable for identifing Alpinia katsumadai from differern geographical regions and cultivation batches, and determining qualitatively and quantitatively their main active components. The determination results of metal elements according to ICP-MS experiments will provide a theoretical foundation for the further development and utilization Alpinia katsumadai and enhancing the food danger consciousness.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117728, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31748164

RESUMO

A synthesized compound, ethyl 2,5-diphenyl-2H-1,2,3-triazole-4- carboxylate (EDTC) was investigated on its physiochemical parameters and structural properties by using the quantum-chemical method. The results on the theoretical spectrum of EDTC were line with experimental fluorescence and absorption spectrum in large degree. Then EDTC was successfully synthesized to a novel rhodamine-based fluorescent probe (REDTC), which showed a distinct fluorescence enhancement upon the presence of Hg2+ in dimethyl formamide-water (DMF-H2O) buffer solution (pH 7.4). Meanwhile, the triazole appended colorless compound turns to pink upon complex formation with Hg2+ ions as 1:2 molar ratios and enables naked-eye detection. The chromogenic mechanism was determined by using spectroscopic measurements and TD DFT calculation. The fluorescence imaging experiments of Hg2+ in HeLa cell revealed that the probe REDTC could be labeled and it could be used in biological systems. Also, the intermediate EDTC was developed as a sensitive fluorescent probe for specific studies on the interactions to three kinds of blood proteins including human serum albumin (HSA), human immunoglobulin (HIg) and bovine hemoglobin (BHb) by using a series of spectroscopic methods and molecular docking under the simulative physiological conditions. The interactions between EDTC and these proteins led to the distinct fluorescence enhancement. The thermodynamic measured results further suggested that hydrophobic forces play a dominating role in stabilizing the complexes, which are in correspondence with the results from molecular docking. The UV-visible, synchronous, and three-dimensional (3D) fluorescence measurements demonstrated that EDTC influences the conformational of proteins and the microenvironment surrounding HSA, HIg, or BHb in aqueous solution.


Assuntos
Proteínas Sanguíneas/metabolismo , Corantes Fluorescentes/química , Mercúrio/análise , Rodaminas/química , Triazóis/química , Animais , Cátions Bivalentes/análise , Bovinos , Corantes Fluorescentes/metabolismo , Células HeLa , Humanos , Simulação de Acoplamento Molecular , Imagem Óptica , Ligação Proteica , Rodaminas/metabolismo , Espectrometria de Fluorescência , Triazóis/metabolismo
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(11): 2557-60, 2008 Nov.
Artigo em Zh | MEDLINE | ID: mdl-19271489

RESUMO

Fourier transform infrared spectrum has been developed for application in the quality control of traditional Chinese medicine, and two new indexes, including common peak ratio and variant peak ratio, were applied, and their values were calculated by means of the sequential analysis for eight kinds of essence oil of Alpinia oxyphylla Miq from different cultural areas (Hainan, Guangxi and Guangdong), in which each sample's IR fingerprint spectra were set up and the common peak ratio and variant peak ratio sequences were arranged in the order of size in comparison with other samples. It can be seen that Alpinia oxyphylla samples from Guangxi, Hainan and Guangdong provinces could be successfully revealed directly by the common peak ratio and variant peak ratio sequences. In comparison with their conventional IR spectra, the primary difference in Alpinia oxyphylla is the intensity of characteristic peaks at 1 710 and 1 666 cm(-1). Considering the spectral range of 400-4 000 cm(-1), the common peak ratio of the spectra between Hainan and Guangdong was 62%, while the common peak ratio between Hainan and Guangxi was 52%. But the mix common peak ratio of the spectra in Hainan is 66%. The fingerprint characters of IR can not only identify the main chemical constituents in medicinal materials, but also compare the components differences among the similar samples. The analytical method is an rapid, effective, fast and advanced to evaluate the production area for pharmaceutical market.


Assuntos
Alpinia/química , Medicamentos de Ervas Chinesas/química , Óleos de Plantas/química , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(12): 2346-9, 2006 Dec.
Artigo em Zh | MEDLINE | ID: mdl-17361747

RESUMO

The characteristics of proton-exchanged and annealed proton-exchanged LiNbO3 optical waveguides were studied by X-ray diffraction and infrared absorption spectroscopy. The X-ray diffraction experiments show that there are diffraction peaks of Lil-x, HxNbO3 on the left of the main peak of the LiNbO3 crystal substrate. This result means that the crystal lattice constant of the layer Li1-x, Hx NbO3 is little larger than that of the LiNbO3 crystal substrate, resulting in a stress. After annealing, the X-ray diffraction peaks of the waveguide layer move towards the main peak of the LiNbO3 crystal substrate, and the stress decreases. The infrared absorption spectroscopy experiments show that there are absorption peaks of OH- at 3 500 and 3 300 cm(-1), and after annealing, the intensity of the absorption peak at 3 300 cm(-1) decreases or disappears, while the intensity of the absorption at 3 500 cm(-1) remains almost invariable. Experiments also show that the integral area of the absorption at 3 500 cm(-1) is proportional to square root te.

6.
J Photochem Photobiol B ; 164: 191-203, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27693762

RESUMO

1-(4-Bromophenyl)-5-phenyl-1H-1,2,3-triazole (BPT) was a newly synthesized compound. The acute toxicities of BPT to mice by intragastric administration have been determined and the result indicates that the intragastric administration of BPT did not produce any significant toxic effect on Kunming strain mice. It is also evaluated for the antimicrobial activity of BPT against three kinds of plant mycoplasma, Fusarium Wilt (race 4), Colletotrichum gloeosporioides Penz. and Xanthomonas oryzae by different method in vitro. The compound exhibited distinct inhibitory activities against Fusarium Wilt (race 4) and Colletotrichum gloeosporioides Penz. by mycelium growth rate test and the values of EC50 were 29.34 and 12.53µg/mL respectively. And BPT had also the most potent inhibitory activities against Xanthomonas oryzae when compared with that of control drugs by the agar well diffusion method. In addition, the structural and photophysical properties of BPT including ionization energy, electron affinities, and theoretical spectrum was studied by quantum-chemical methods. Then the interaction of BPT with two kinds of globular proteins, human immunoglobulin (HIg) and bovine hemoglobin (BHg) was investigated by using UV-vis absorption spectra, synchronous fluorescence, 3D fluorescence spectra, and fluorescence titration in combination with molecular modeling. UV-vis absorption, 3D and synchronous fluorescence measurements show that BPT has influence on the microenvironment surrounding HIg or BHg in aqueous solution and the fluorescence experiments show that BPT quenches the fluorescence intensity of HIg or BHg through a static mechanism. The binding parameters including the binding constants, the number of binding site and average binding distance between BPT and HIg or BHg at different temperatures were calculated. The thermodynamic parameters suggest that the hydrophobic interaction is the predominant intermolecular forces in stabilizing the BPT-HIg or BPT-BHg complex. Molecular docking was performed to reveal that the BPT moiety binds to the hydrophobic cavity of HIg or BHg and they are in good agreement with the spectroscopic measurements.


Assuntos
Anti-Infecciosos/farmacologia , Anti-Infecciosos/toxicidade , Triazóis/toxicidade , Animais , Anti-Infecciosos/metabolismo , Bovinos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Ligação Proteica , Triazóis/metabolismo , Triazóis/farmacologia
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(3): 303-4, 2004 Mar.
Artigo em Zh | MEDLINE | ID: mdl-15759981

RESUMO

Z-cut proton-exchanged LiNbO3 optical waveguides exchanged with different proton sources mixed with adipic acid and benzoic acid in different mol ratios were analyzed by infrared absorption spectroscopy. The result shows that there is an absorption peak of OH- free group at 3500 cm(-1) with the characteristic of substitute protons, and the absorption peak of H-bond is nearby 700 cm(-1) with the characteristic of packing protons. The different mixing ratios and different concentrations of H+ in the proton source, result in different proton-exchanged velocities and bring on the change in these absorption peaks. It is very important to study the change in these absorption peaks for making high quality LiNbO3 optical waveguide.

8.
Nat Prod Commun ; 8(10): 1427-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24354193

RESUMO

Two new compounds, (+)-rumphiin (3) and polyalthurea (7), together with seven known ones, 3,4,5-trimethoxy benzoic acid (1), (-)-seselinone (2), cannabisin D (4), allantoin (5), oxostephanine (6) and a mixture of beta-sitosterol (8) and stigmasterol (9) were isolated from the stems of Polyalthia rumphii. The chemical structures of 3 and 7 were elucidated by the combination of spectroscopic data, and the absolute configuration of 3 at C-2 was determined by the matrix method to be R. All compounds were evaluated for their cytotoxicity on four human cancer cell lines, which demonstrated that 3 was a moderate bioactive lignan, and 6 showed significant anticancer activity against SPC-A-1 and BEL-7402 cell lines with IC50 values of 1.47 and 1.73 microg/mL, respectively.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Ácido Gálico/análogos & derivados , Polyalthia/química , Alantoína/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Ácido Gálico/química , Ácido Gálico/isolamento & purificação , Humanos , Células K562 , Lignanas/isolamento & purificação , Caules de Planta/química , Sitosteroides/isolamento & purificação , Estigmasterol/isolamento & purificação
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