PubMed | Shanghai Institute of Forensic Science, Shanghai Institute of Pharmaceutical Industry and Shanghai Institute of Technology
Type: Journal Article | Journal: Bioscience, biotechnology, and biochemistry | Year: 2016
Fluoroacetamide (Mw=77.06) is a lethal rodenticide to humans and animals which is still frequently abused in food storage somewhere in China. The production of antibodies for fluoroacetamide is difficult due to its high toxicity to animals, which limits the application of immunoassay method in poison detection. In this work, aptamers targeting N-fluoroacetyl glycine as an analog of fluoroacetamide were selected by a specific systematic evolution of ligands by exponential enrichment (SELEX) strategy. The binding ability of the selected aptamers to fluoroacetamide was identified using surface plasmon resonance (SPR)-based assay. The estimated KD values in the low micromolar range showed a good affinity of these aptamers to the target. Our work verified that the SELEX strategy has the potential for developing aptamers targeted to small molecular toxicants and aptamers can be employed as new recognition elements instead of antibodies for poison detection.
Liu X.,Fudan University |
Zheng S.,Shanghai Institute of Forensic Science |
Jiang Z.,Thermo Fisher Scientific |
Liang C.,Shanghai Institute of Forensic Science |
And 4 more authors.
Journal of Separation Science | Year: 2014
An in vivo study of Strychnos alkaloids metabolites in rats by ultra high performance liquid chromatography with linear ion trap Orbitrap MS is reported for the first time. Two major Strychnos alkaloids compounds including strychnine and brucine were investigated. To obtain optimal extraction efficiency, samples were pretreated by using an SPE plate. The structures of metabolites and their fragment ions were characterized based on the accurate mass and MSn data. Forty-seven metabolites were identified in rat urine, of which 25 were reported for the first time. Four new metabolism pathways were proposed on the basis of the identified metabolites. This study provides a practical approach for rapidly identifying complicated metabolites, a methodology that could be widely applied not only in forensic and clinically toxicological relevant cases, but also for the structural characterization of metabolites of other compounds. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Yu Z.,Fudan University |
Wu Z.,Shanghai Institute of Forensic Science |
Gong F.,Shanghai Institute of Forensic Science |
Wong R.,Shanghai Institute of Forensic Science |
And 3 more authors.
Journal of Separation Science | Year: 2012
A novel capillary zone electrophoresis separation coupled to electro spray ionization time-of-flight mass spectrometry method was developed for the simultaneous analysis of six toxic alkaloids: brucine, strychnine, atropine sulfate, anisodamine hydrobromide, scopolamine hydrobromide and anisodine hydrobromide in human plasma and urine. To obtain optimal sensitivity, a solid-phase extraction method using Oasis MCX cartridges (1 mL, 30 mg; Waters, USA) for the pretreatment of samples was used. All compounds were separated by capillary zone electrophoresis at 25 kV within 12 min in an uncoated fused-silica capillary of 75 μm id × 100 cm and were detected by time-of-flight mass spectrometry. This method was validated with regard to precision, accuracy, sensitivity, linear range, limit of detection (LOD), and limit of quantification (LOQ). In the plasma and urine samples, the linear calibration curves were obtained over the range of 0.50-100 ng/mL. The LOD and LOQ were 0.2-0.5 ng/mL and 0.5-1.0 ng/mL, respectively. The intra- and interday precision was better than 12% and 13%, respectively. Electrophoretic peaks could be identified by mass analysis. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Wang X.,Shanghai Institute of Pharmaceutical Industry |
Wang X.,Shanghai Institute of Forensic Science |
Wang R.,Shanghai Institute of Forensic Science |
Zhang Y.,Shanghai Institute of Forensic Science |
And 4 more authors.
Journal of Chromatography A | Year: 2012
A method for the simultaneous direct analysis of diazepam oxazepam glucuronide, temazepam glucuronide, oxazepam, nordiazepam, and temazepam in human urine was developed and validated. Urine sample was purified by solid phase extraction (SPE), and the analysis was achieved using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system equipped with an electrospray ionization source (ESI). Multiple reaction monitoring (MRM) mode was used to analyze the target compounds. Extraction recoveries were 65-122% for all the analytes. The method showed acceptable intra-assay and inter-assay precision (both relative standard deviation (RSD) ≤ 11.2%) for quality control (QC) samples. The limits of detections (LODs) were in the range of 0.1-2. ng/mL. The present assay was applied to analyze the urine obtained from three volunteers after oral administration of a single dose 5. mg of diazepam. The results showed that, the detection periods of oxazepam glucuronide and temazepam glucuronide were much longer than diazepam and other metabolites. © 2012 Elsevier B.V.
Guo L.,Shanghai University of Traditional Chinese Medicine |
Lin Z.,Fudan University |
Huang Z.,Fudan University |
Liang H.,Fudan University |
And 6 more authors.
Forensic Toxicology | Year: 2015
We developed a simple and rapid analysis method for the determination of four amphetamines in human whole blood and urine using gas chromatography–mass spectrometry (GC–MS). During the course of sample preparation, the evaporation process was found to be the weak point for amphetamine and methamphetamine analysis. Liquid–liquid extraction in this study was conducted without the evaporation step, and the upper solvent layer was injected directly without derivatization, which effectively prevented the volatile amphetamines from vanishing during evaporation and guaranteed the linearity of the calibration curves. This method showed good selectivity, precision, and accuracy, and at the same time was simple and fast. The limits of detection were 5 ng/ml. As an application of this study, a whole blood sample and urine sample from a drug abuse suspect were analyzed. This method may be able to meet the need for rapid and accurate confirmation of positive immunoassay results as well as quantification in clinical and forensic toxicological cases. To our knowledge, no forensic toxicologists have noted that such a basic and simple method, without evaporation or derivatization, is useful for routine analysis of amphetamines using GC–MS. © 2014, Japanese Association of Forensic Toxicology and Springer Japan.
PubMed | Shanghai Institute of Forensic Science and Fudan University
Type: Journal Article | Journal: Journal of separation science | Year: 2015
A liquid chromatography with tandem mass spectrometry method was developed for the simultaneous screening of 34 drugs and poisons in forensic cases. Blood (0.5 mL, diluted 1:1 with water) or 1.0 mL of urine was purified by solid-phase extraction. Gastric contents (diluted 1:1 with water) were treated with acetonitrile, centrifuged, and supernatant injected. Detection was achieved using a Waters Alliance 2695/Quattro Premier XE liquid chromatography tandem mass spectrometry system equipped with electrospray ionization, operated in the multiple reaction monitoring modes. The method was validated for accuracy, precision, linearity, and recovery. The absolute recovery of drugs and toxic compounds in blood was greater than 51% with the limit of detection in the range of 0.02-20 ng/mL. The absolute recovery of drugs and toxic compounds in urine was greater than 61% with limit of detection in the range of 0.01-10 ng/mL. The matrix effect of drugs and toxic compounds in urine was 65-117% and 67-121% in blood. The limit of detection of drugs and toxic compounds in gastric content samples were in the range of 0.05-20 ng/mL. This method was applied to the routine analysis of drugs and toxic compounds in postmortem blood, urine, and gastric content samples. The method was applied to actual forensic cases with examples given.
PubMed | Shanghai Institute of Forensic Science, Chinese Academy of Sciences, Copenhagen University and Fudan University
Type: Journal Article | Journal: International journal of legal medicine | Year: 2016
Only sporadic data are available on hair concentrations of diazepam and some of its metabolites (nordazepam, oxazepam, and temazepam) following a single controlled dose. The aim of this study was to investigate the deposition of diazepam and its metabolites in human hair after eight healthy volunteers (four women and four men, ages 24-26, East Asian) consumed 10mg of diazepam. Hair was collected from all volunteers 1month after exposure, and also 2months post-exposure from men and 10months post-exposure from women. Diazepam and the complete metabolite profile, including oxazepam glucuronide and temazepam glucuronide, were measured by ultra-high pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) with limits of quantifications (LOQs) of 0.5-2.5pg/mg for diazepam, nordazepam, oxazepam, and temazepam, and of 10pg/mg for oxazepam glucuronide and temazepam glucuronide. There were no differences by gender in the amounts of diazepam or metabolites found. The concentration of the main metabolite nordazepam was consistently higher than that of diazepam at both 1 and 2months after consumption. Oxazepam and temazepam traces were found in some volunteers hair, but the glucuronides were not detected. Diazepam and nordazepam levels at 10months post-exposure were extremely low (near the LOQ), indicating drug loss by personal hygiene and physical handling. To our knowledge, this is the first single-dose diazepam study using black hair and the first study to include measurements of oxazepam glucuronide and temazepam glucuronide in human hair.
PubMed | Fudan University, Shanghai Institute of Forensic Science and Copenhagen University
Type: Journal Article | Journal: Journal of separation science | Year: 2016
A novel and simple online solid-phase extraction liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous determination of diazepam and its five metabolites including nordazepam, oxazepam, temazepam, oxazepam glucuronide, and temazepam glucuronide in human oral fluid. Human oral fluid was obtained using the Salivette() collection device, and 100 L of oral fluid samples were loaded onto HySphere Resin GP cartridge for extraction. Analytes were separated on a Waters Xterra C18 column and quantified by liquid chromatography with tandem mass spectrometry using the multiple reaction monitoring mode. The whole procedure was automatic, and the total run time was 21 min. The limit of detection was in the range of 0.05-0.1 ng/mL for all analytes. The linearity ranged from 0.25 to 250 ng/mL for oxazepam, and 0.1 to 100 ng/mL for the other five analytes. Intraday and interday precision for all analytes was 0.6-12.8 and 1.0-9.2%, respectively. Accuracy ranged from 95.6 to 114.7%. Method recoveries were in the range of 65.1-80.8%. This method was fully automated, simple, and sensitive. Authentic oral fluid samples collected from two volunteers after consuming a single oral dose of 10 mg diazepam were analyzed to demonstrate the applicability of this method.
PubMed | Shanghai Institute of Forensic Science, Fudan University and Shanghai Institute of Pharmaceutical Industry
Type: | Journal: Journal of chromatography. A | Year: 2015
Co-administration of opioids with benzodiazepines is very common around the world. A semi-automated method was developed for the determination of four opioids and two benzodiazepines as well as their metabolites (including glucuronide metabolites) in human urine, based on on-line column-switching-solid-phase extraction (CS-SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The CS-SPE was performed by loading 200L of urine sample to an Oasis HLB cartridge. Detection was achieved using a LC-MS/MS system equipped with an electrospray ionization source (ESI). For unequivocal identification and confirmation, two selected reaction monitoring transitions were registered for each compound, and no co-elution of interferences was observed at the expected retention time. Significant ion suppressions were observed for most analytes during chromatographic runs, but isotope-labeled internal standards (ISs) were used and found to be useful to compensate for the determination error caused by the matrix effect. The assays linearity ranged from 1-20ng/mL to 800-1000ng/mL for 23 compounds, except for lorazepam (LOR), whose linearity was in the range of 1-100ng/mL. This method showed to be precise and accurate. The relative standard deviation (RSD) % values of within-run precision, between-run precision and total precision were not greater than 10.4% (n=3), 12.9% (n=5) and 15.1% (n=15), respectively. Accuracy values were in the range of 87.5-110%. Limits of detection (LODs) ranged from 0.2ng/mL to 5ng/mL, and limits of quantification (LOQs) ranged from 1ng/mL to 20ng/mL. The method was applied to the assay of 12 samples from forensic cases, which exemplified the co-administration of benzodiazepines (BZDs) by some heroin abusers. This method was of high sensitivity, selectivity and reliability, minimum sample manipulation, semi-automation, and fairly high throughput (analysis time per sample was 20min). The method developed will be useful for the detection of co-administrated drugs and the study of the interactions of BDZs with opioids.
Xiong Z.,East China University of Science and Technology |
Zhang L.,East China University of Science and Technology |
Zhang R.,Shanghai Institute of Forensic Science |
Zhang Y.,Shanghai Institute of Forensic Science |
And 2 more authors.
Journal of Separation Science | Year: 2012
A simple and effective preconcentration method based on magnetic core-shell silica nanoparticles with C18-modified surface was developed for the analysis of pesticide residues in environmental water samples by gas chromatography-mass spectrometry. Several kinds of organophosphorous and pyrethroid pesticides including methamidophos, dichlorvos, orthene, phorate, dimethoate, carbofuran, bifenthrin, fenpropathrin, cypermethrin, fenvalerate, and deltamethrin were used as model compounds to systematically evaluate the method. Various parameters, including the amounts of magnetic nanoparticles absorbents, extraction time, eluting solvent, eluting volume, and sample pH values were optimized. The optimized method affords low detection limits (signal-to-noise ratio = 3) from 0.001 to 0.008 μg/L, and shows good linearity with correlation coefficients over 0.9990 in the concentration range of 0.025-0.5 μg/L. Average recoveries at three spiked levels were in the range of 70.2-110.2% with relative standard deviations below 9.6%. A maximum enrichment factor of 1015 times was achieved. Analysis results of poisoned pond water indicate that this method is fast, convenient, and efficient for the detections of low-concentration pesticides in aqueous samples. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.