Simple and rapid detection of three amatoxins and three phallotoxins in human body fluids by UPLC-MS-MS and its application in 15 poisoning cases.

Amatoxins and phallotoxins are toxic cyclopeptides found in the genus Amanita and are among the predominant causes of foodborne sickness and poisoning-related fatalities in China. This study introduces and validates a simple, rapid and cost-effective ultra-performance liquid chromatography-mass spectrometry method for the simultaneous determination and quantification of α-amanitin, ß-amanitin, γ-amanitin, phallisacin, phallacidin and phalloidin in human blood and urine. Quick therapeutic decision-making is supported by a 9 min chromatographic separation performed on a Waters Acquity UPLC HSS T3 column (100 mm × 2.1 mm, 1.8 µm) using a gradient of high-performance liquid chromatography (HPLC)-grade water and methanol:0.005% formic acid. The analyte limit of quantification was 1-3 ng/mL in blood and 0.5-2 ng/mL in urine. Calibrations curves, prepared by spiking drug-free blood and urine, demonstrated acceptable linearity with mean correlation coefficients (r) greater than 0.99 for all phallotoxins and amatoxins. Acceptable intraday and interday precision (relative standard deviation <15%) and accuracy (bias, -4.8% to 13.0% for blood and-9.0% to 14.7% for urine) were achieved. The validated method was successfully applied to analyze 9 blood samples and 2 urine samples testing positive for amatoxins and/or phallotoxins. Amatoxins and/or phallotoxins were identified in each whole blood sample at a range of 1.12-5.63 ng/mL and in two urine samples from 1.01-9.27 ng/mL. The method has the benefits of simple sample preparation (protein precipitation) and wide analyte coverage, making it suitable for emergency quantitative surveillance toxicological analysis in clinics and forensic poisoning practice.

Development of an LC-MS/MS method for the determination of multiple mycotoxins in human urine.

A sensitive liquid chromatography-tandem mass spectrometry method was developed for the determination of 17 mycotoxins in human urine. The method incorporates a two-step liquid-liquid extraction with ethyl acetate:acetonitrile (7:1), which had good extraction recovery. The LOQs of all mycotoxins ranged from 0.1 to 1 ng/mL. Intra-day accuracy ranged from 94 to 106%, and intra-day precision ranged from 1 to 12% for all mycotoxins. Inter-day accuracy and precision were 95-105% and 2-8%, respectively. The method was successfully applied to investigate the urine levels of 17 mycotoxins from 42 volunteers. Deoxynivalenol (DON, 0.97-9.88 ng/mL) was detected in 10 (24%) urine samples and zearalenone (ZEN, 0.13-1.11 ng/mL) in 2 (5%) urine samples.

Metabolic profiling of clonazolam in human liver microsomes and zebrafish models using liquid chromatography quadrupole Orbitrap mass spectrometry.

Clonazolam is a designer benzodiazepine with strong sedative and amnesic effects. As we all know, the detection of metabolites is the key to confirming the use of substances in the field of forensic toxicology. In order to better describe clonazolam metabolism completely, we performed the two different experiments exploiting the unique characteristics of the models used. In this study, in vivo and in vitro samples were analyzed with liquid chromatography-quadrupole/electrostatic field orbitrap mass spectrometry. The results showed that seven Phase I metabolites and one Phase II metabolite were detected in zebrafish model. The remaining Phase I and II metabolites were also found in the incubation solution of pooled human liver microsomes. The main types of metabolic reactions of clonazolam included hydroxylation, dealkylation, nitroreduction, dechlorination, N-Acetylation, and O-glucuronidation. In this paper, the main metabolites and metabolic pathways of clonazolam are clarified in detail in order to further improve the metabolic rule of clonazolam. Based on these results, to better detect and judge the abuse of clonazolam, we suggest that M1, its nitro reduction product, is used as its biomarker. The results of this study provide a theoretical basis for the pharmacokinetics and forensic medicine of clonazolam.

Detection of mescaline in human hair samples by UPLC-MS/MS: Application to 19 authentic forensic cases.

Mescaline, a natural alkaloid found in the peyote cactus (Lophophora williamsii) in the Americas, has gradually become a drug of abuse in China because of its psychedelic properties. Its intake may lead to hallucinations and confusion or even be life-threatening. Mescaline is classified as a class Ⅰ psychotropic drug in China, which means its use in medicine or scientific research is under strict control of the government. However, studies on surveillance of mescaline abuse in the Chinese population are lacking. A rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the determination and quantification of mescaline in hair. The method had good linearity in the range from 10 to 1000 pg/mg, with the limit of detection (LOD) of 3 pg/mg and the limit of quantitation (LOQ) of 10 pg/mg. The total runtime was 5 min. Acceptable intraday and interday precision (RSD < 15%) and accuracy (bias, -11.2% ∼ 6.8%) were achieved. The recovery was 85.0-101.0%, and the matrix effect was 92.0-105.0%. The validated method was successfully applied to 19 real forensic cases. The concentrations of mescaline in hair ranged from 10 to 784 pg/mg. The method has the benefits of simple sample preparation, high sensitivity, and short running time, making it suitable for large-scale quantitative surveillance analysis of mescaline in forensic toxicology.