Time filter

Source Type

Zhang S.,Chongqing Traffic Management Bureau | Cao J.-H.,Chongqing Traffic Management Bureau | Liu W.-W.,Chongqing Institute of Forensic Science
Journal of Chinese Mass Spectrometry Society | Year: 2015

O6-Monoacetylmorphine, morphine, morphine-3-β-D-glucuronide in addicts' blood samples were analyzed by solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The samples were extracted by extraction column (Oasis HLB), and then were flushed into the analytical column (AtlantisTM dC18 (150 mm×3.9 mm×5 μm)) with methanol and water containing formic acid as mobile phase and morphine-3-β-D-glucuronide-d3 as internal standard. The positive electric spray ionization, multiple reaction monitoring (MRM) mode were applied to analyze target compounds. Identification was based on the compound's retention time and two pairs of precursor-to-product ion transitions. The results show that the limit of detections are 3-5 μg/L for morphine, O6-monoacetylmorphine and morphine-3-β-D-glucuronide. The linear relationship is well, and the linear correlation coefficient is greater than 0.997 5. The average recoveries are 80.6%-98.9% with the spiked levels of 50, 500, 1 000 μg/L, and the accuracies are -7.3%-9.1%. The method has high sensitivity and selectivity, which is suitable for analyzing the heroin and its metabolites in addicts' blood samples. ©, 2015, Chinese Society for Mass Spectrometry. All right reserved. Source

Yu B.,Zhengzhou University | Qi P.-P.,Zhengzhou University | Shi X.-J.,Zhengzhou University | Huang R.,Central South University | And 4 more authors.
European Journal of Medicinal Chemistry | Year: 2016

A series of steroidal hybrids with different terminal bioactive scaffolds were synthesized using the molecular hybridization approach and further evaluated for their antiproliferative activity against several cancer cell lines of different origins using the MTT assay. The preliminary results indicated that compounds 12a-h with the terminal isatin motif were remarkably sensitive to SH-SY5Y cells, thereby exerting potent growth inhibition in vitro. This selectivity is possibly attributed to LSD1 inactivation (IC50 = 3.18 μM). Besides, we also found that the chloro atom at the 7-position on the isatin core was beneficial for the activity through the SARs studies. Among this series, compound 12g showed the best inhibitory activity (IC50 = 4.06 μM) against SH-SY5Y cells, which was comparable to that of 5-FU. Compound 12g arrested cell cycle at G2/M phase, induced apoptosis accompanied with decrease of mitochondrial membrane potential, and inhibited LSD1 potently (IC50 = 3.18 μM). Docking studies showed that compound 12g formed interactions with surrounding amino acid residues and the steroid nucleus occupied the tubular hydrophobic cavity of the active site. Compounds 13-18 represented weak to moderate activity against the tested cancer cell lines. The steroidal dimer 20 and the structurally simplified non-steroidal dimer 21 were found to be devoid of the inhibitory activity. © 2016 Elsevier Masson SAS. All rights reserved. Source

Gao X.,Chongqing Technology and Business University | Guo H.,Chongqing Institute of Forensic Science | Du Y.,Hospital of Traditional Chinese Medicine | Gu C.,EnerVault
Journal of Analytical Toxicology | Year: 2015

Xylazine as veterinary medicine for sedation, but intoxication cases in humans were identified in the last few years. A highly sensitive method is required for analyzing xylazine and its metabolites in human blood and urine. This article presents an ultra high performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry (UHPLC-QTOF) study for simultaneous determination of xylazine and 2,6-dimethylaniline (DMA) in human blood and urine. The samples were extracted and cleaned up by Oasis MCX solid-phase extraction. The analysis is performed using an UHPLCQTOF. Analysis precision, accuracy, sensitivity, linear range, limit of detection (LOD) and limit of quantification (LOQ) were validated for the proposed method. In the blood and urine samples, the linear calibration curves with high linearity are obtained over the range of 2.0- 1,000.0 ng/mL. The LOD for xylazine and DMA in blood are 0.2 and 0.1 ng/mL, in urine are 0.4 and 0.2 ng/mL; the LOQ for xylazine and DMA in blood are 0.6 and 0.3 ng/mL, in urine are 1.0 and 0.6 ng/mL, respectively. The intra- and interday precision is better than 8.6 and 11.9%. In conclusion, the proposed method is highly sensitive and reproducible, thus suitable for accurate quantification of xylazine and its metabolites in blood and urine. © The Author 2015. Source

Shi Y.,Chongqing Institute of Forensic Science | Guo J.,Chongqing Institute of Forensic Science | Wang H.,Chongqing Institute of Forensic Science | Duan J.,Chongqing Institute of Forensic Science | And 3 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2014

A high-throughput method was developed for screening antidepressants in blood by automated solid phase extraction and liquid chromatography with high resolution quadrupole-time-of-flight mass spectrometry ( ASPE-LC-Q-TOF/MS). The samples were cleaned up by an HLB solid phase extraction cartridge and analyzed by LC-Q-TOF/MS under electrospray ionization ( ESI) mode with scanning range of m/z 50-1 000 Da. The chromatographic separation was performed on an Agilent Eclipse Plus C18 column (50 mm × 2.1 mm, 1. 8 μm) with gradient elution using methanol and 5 mmol/L ammonium formate aqueous solution ( containing 0. 2% formic acid ) as mobile phases. Rapid screening and confirmation can be achieved using MS matching scores, deviation of retention time, measured mass, isotopic abundance matching scores, isotope space matching scores and MS/MS matching scores. The quantitative analysis was carried out by correlating the extracting peak area with accurate mass. Good linearities were observed in the range of 1-500 μg/L with the correlation coefficients from 0. 997 6 to 0. 999 7. The limits of detection were 0.01-0.5 μg/L. The spiked recoveries were 79.6%-96.4% with the relative standard deviations of 4. 1% 6.4%. The result screening database was built us ng Ag lent MassHunter PCDL Manager software and then used for the analys s of sp ked samples. MS matching scores, isotopic abundance matching scores, isotope space matching scores (all > 95 points) and MS/MS matching scores (> 70 points ) were applied to identify the ana-lytes. The results showed that all the sp ked ant depressants could be correctly dent f ed w th low deviation of retention time (< 0. 1 min) and mass ( < 1 mDa). The developed method was further applied for the analysis of poisoning cases, and amitriptyline, carbamazepine, doxepin were detected. In brief, the method is rapid, sensitive, simple, reliable, and suitable for the screening and confirmation of ant depressantsin forensic and clinical analytical toxicology. Source

Guo J.,Chongqing Institute of Forensic Science | Xu J.,Chongqing Institute of Forensic Science | Guo H.,Chongqing Institute of Forensic Science
Chemistry Bulletin / Huaxue Tongbao | Year: 2014

A method for detecting amitraz pesticide residues in paddy field water by liquid phase extraction combining with GC-MS was established. The influences of solvent and pH value on extraction efficiencies were investigated. The analysis was performed by selected ion monitoring (SIM) mode. Under the optimal conditions, the calibration curve of amitraz was in the range of 20~2000ng/mL with a correlation coefficient of 0.9991. The average recoveries were 86.7% with RSD of 5.3%. The detection limit was 10ng/mL. The results showed that the method is rapid, sensitive and accurate, and can be used to detect of amitraz in paddy field water. Source

Discover hidden collaborations