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Lin Q.-B.,University of Jinan | Che L.-L.,Shanxi University | Guo J.,Shanxi Academy of Analytical science | Wang R.-Z.,Shanxi Academy of Analytical science
Food Analytical Methods

Ultrahigh-performance liquid chromatography tandem mass spectrometry with 4-chloro-3,5-dinitrobenzotrifluoride (CNBF) derivatization was developed for simultaneous determination of 20 free amino acids in Chinese jujube date. The MS/MS conditions, choice of mobile phase, the extraction process, and matrix effects were studied with a view to a method of optimization. The limits of detection for measurement of the amino acids ranged from 0.8 to 600.0 μg L-1. The correlation coefficients (r2 ≥ 0.9947) indicated good correlation between the concentrations of amino acids and the peak areas for the CNBF-derivatives. Recoveries for samples spiked at 25.0, 50.0, and 100.0 mg kg-1 ranged from 66.3 to 106.6 % (except tryptophan spiked at 25.0 and 50.0 mg kg-1, which provided recoveries of 61.2 and 60.4 %, and tyrosine spiked at three different concentrations, which provided recoveries of 54.8-58.6 %), with relative standard deviation values of less than 9.1 %. © 2013 Springer Science+Business Media New York. Source

Sun Y.,Taiyuan University of Technology | Fan S.,Taiyuan University of Technology | Zhang S.,Shanxi Academy of Analytical science | Zhao D.,Taiyuan University of Technology | And 2 more authors.
Sensors and Actuators, B: Chemical

A new fluorescent turn-on probe for HSO3 - bearing a benzo[e]indolium moiety was developed. The HSO3 - undergoes 1,4-addition reaction with the C-4 atom in the ethylene group, resulting in a prominent fluorescence enhancement and a fluorescent color change. The reaction could be completed in 1 min in PBS buffer, and displayed a high selectivity and sensitivity for HSO3 - against other anions, including CN-. Moreover, the practical value of the probe was confirmed by application to detect the level of HSO3 - in sugar samples. © 2013 Elsevier B.V. Source

Zhang S.,Shanxi Academy of Analytical science
Gongneng Cailiao/Journal of Functional Materials

A new type of fluorene derivative, 2-(2, 4-difluorophenyl)-7-(4-methoxyphenyl)-9, 9-dioctylfluorene(compound 1) was synthesized and characterized by elemental analysis, IR spectra and NMR Spectroscopy. Its optoelectric properties were measured by UV-Vis absorption spectra and fluorescence spectra. The results show that compound 1 has low-energy absorption bands ranging from 350 nm to 400 nm in dichloromethane solution, which can be assigned to the π-π* charge transfer transitions. The optical band gap (Eg) of compound 1 was estimated to be 3.39 eV. The title compound exhibits strong blue photoluminescence under 310 nm excitation at room temperature. The fluorescence quantum yields of compound 1 in CH2Cl2 was up to 0.70. In addition, the wavelength of the absorption and emission spectra of compound 1 depend on the polarities of the solvents. ©, 2014, Journal of Functional Materials. All right reserved. Source

Zhang M.,Shanxi University | Xie J.,Shanxi University | Wang Z.,Shanxi University | Zhao L.,Shanxi University | And 2 more authors.
Atmospheric Research

Sixteen polycyclic aromatic hydrocarbons (PAHs) present in PM2. 5 were analyzed in 2012 in Taiyuan (China) using high performance liquid chromatography (HPLC) with fluorescence and ultraviolet detectors. The average daily mass concentrations of σPAHs in different seasons ranged from 10.36 ng/m3 to 215.93 ng/m3 and had strong seasonal variation, with highest values in winter and lowest in summer. Over the whole year, PAHs appeared in the following order of frequency: 4-ring > 6-ring > 5-ring > 3-ring; in winter, the percentage of 4-ring PAHs was the highest (62.68%), while in summer, the percentages of 5-ring and 6-ring PAHs (cumulative total of 50.57%) were higher. The ratio method was employed to investigate potential source categories of PAHs in PM2.5 in Taiyuan, with data suggesting that the main PAH sources are coal and wood combustion and vehicle emissions. Finally, a risk assessment of PAHs was performed based on benzo(a)pyrene equivalent (BaPeq) values and individual cancer risk ratios, with results suggesting that the toxicity of PAHs was high during winter and spring time in Taiyuan. The values of incremental lifetime cancer risk (ILCR) induced by whole year inhalation exposure(Ri) for all age groups were larger than 10-6 in spring and winter, while Ri values for male and female adults in summer and autumn were also larger than 10-6, indicating high potential carcinogenic risk. During the same season, the ILCR of adults was greater than that of other age groups and that of females was a little higher than of males. With respect to the season, the ranking of ILCR in decreasing order was as follows: winter, spring, autumn, and summer. © 2016 Elsevier B.V. Source

Liu Y.,Shanxi University | Zhang S.,Shanxi Academy of Analytical science | Lv X.,Shanxi University | Sun Y.-Q.,Shanxi University | And 2 more authors.

A but-3-yn-2-one-based 7-diethylaminocoumarin dye was exploited as a fluorescent probe to specifically detect Cys over Hcy/GSH in pure PBS buffer. The probe itself is nonfluorescent due to the donor-excited photoinduced electron transfer (d-PET) process. The Cys-induced Michael addition- rearrangement cascade reaction leads to an amino-substituted product 3a with strong fluorescence due to inhibiting CC isomerization induced fluorescence quenching by a produced intramolecular N-H⋯O hydrogen bond. The Hcy (or GSH)-induced Michael addition reaction leads to a thiol-substituted product 2b (or 4), which lacks any intramolecular hydrogen-bonding interaction, and thus displays very poor fluorescence due to the efficient CC isomerization induced fluorescence quenching. Even in the presence of Hcy (or GSH), the probe could also detect Cys with the obvious fluorescence enhancement. Assisted by using a laser scanning confocal microscope, we demonstrated that the probe could selectively image Cys in the human renal cell carcinoma 786-0 cells. This journal is © the Partner Organisations 2014. Source

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