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Ping Xiang

Department of Forensic Toxicology, Academy of Forensic Science, Shanghai Key Laboratory of Forensic Medicine (21DZ2270800), Shanghai Forensic Science Platform, Key Laboratory of Forensic Sciences, Ministry of Justice, Shanghai, PR China. Electronic address: xiangping2630@163.com.

11 papers in the library · 51 citations · publishing 2021-2025

Papers

Analysis of 28 hair samples from users of the hallucinogenic beverage ayahuasca

Forensic Science International April 20, 2021 Mengxi Liu, Huan Yang, Jing Hu et al. 14 citations

A fast and reliable UPLC-MS/MS method was developed and validated for measuring dimethyltryptamine (DMT) in hair samples. The method, which pulverizes 20-milligram hair samples with methanol below 4 °C, achieved a lower limit of quantitation of 3 pg/mg and a calibration curve with R² = 0.992. Intraday and interday precision (RSD < 15%) and accuracy (92-113%) were acceptable, and dilution integrity was confirmed. Applied to 28 forensic cases, DMT concentrations ranged from 3 to 1109 pg/mg.

Sensitive quantitative analysis of psilocin and psilocybin in hair samples from suspected users and their distribution in seized hallucinogenic mushrooms

Forensic Toxicology February 2, 2021 Liying Zhou, Ping Xiang, Di Wen et al. 13 citations

A highly sensitive method for measuring psilocin and psilocybin in hair samples from magic mushroom users was developed using ultra-high pressure liquid chromatography coupled with tandem mass spectrometry. The technique achieved a detection limit of 1 pg/mg and a quantification limit of 5 pg/mg, with linear calibration from 5 to 500 pg/mg. In two authentic hair samples, psilocin concentrations were 161 and 150 pg/mg, while psilocybin was not detected. The method also analyzed psilocin and psilocybin distribution in seven hallucinogenic mushrooms. This represents the first measurement of psilocin in hair from hallucinogenic mushroom consumers and the most sensitive quantitative method for these compounds in hair.

Natural or artificial: An example of topographic spatial distribution analysis of mescaline in cactus plants by matrix-assisted laser desorption/ionization mass spectrometry imaging

Frontiers in Plant Science February 10, 2023 Jiaman Lin, Shuo Yang, Jiaojiao Ji et al. 8 citations

Mescaline, the hallucinogenic compound found in certain cacti such as Trichocereus pachanoi and Lophophora williamsii, is not distributed uniformly in natural plants. Using liquid chromatography-mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry imaging, the spatial distribution of mescaline was mapped at macroscopic, tissue, and cellular levels. In natural plants, mescaline concentrated in active meristems, epidermal tissues, and protruding parts. Artificially spiked Lophophora diffusa products showed no such topographic difference, allowing natural and artificial products to be distinguished. The overlap of mescaline distribution with vascular bundles supported the known synthesis and transport theory of mescaline, suggesting the technique's potential for botanical research.

Tentative identification of in vitro metabolites of O‐acetylpsilocin (psilacetin, 4‐AcO‐DMT) by UHPLC‐Q‐Orbitrap MS

Drug Testing and Analysis March 21, 2022 Wenya Zhai, Le Li, Junbo Zhao et al. 5 citations

4-Acetoxy-N,N-dimethyltryptamine (4-AcO-DMT, psilacetin) is a synthetic psychedelic that may act as a precursor to psilocin, but its metabolism was poorly understood. Incubating 4-AcO-DMT with pooled human liver microsomes produced 15 metabolites: 12 from phase I and 3 from phase II reactions. Transformations included hydrolysis, hydroxylation, N-demethylation, oxidation, and glucuronic acid conjugation. The hydrolysis product was the most abundant. For forensic detection of 4-AcO-DMT use, the beta-hydroxylation metabolite (M2-1) is recommended as a biomarker. These findings may help predict in vivo metabolism and assist drug testing.

High-throughput screening of 311 new psychoactive substances and metabolites in wastewater by direct injection UPLC-MS/MS.

Journal of chromatography. B, Analytical technologies in the biomedical and life sciences August 1, 2025 Yue Xiao, Shuai Yuan, Ruxin Luo et al. 3 citations

A high-throughput screening method using direct injection was developed to detect 311 new psychoactive substances (NPS) and their metabolites in wastewater, covering synthetic cannabinoids, cathinones, phenylethylamines, tryptamines, phencyclidines, benzodiazepines, fentanyls, and piperazines. The method runs in 16 minutes, with 95.8% of targets having a limit of detection at or below 10 ng/L and recoveries between 71.01% and 119.88%. Applied to 976 real samples from a Chinese city, it identified 32 substances, with ketamine detected most frequently. This approach offers a simple analytical tool for wastewater monitoring to support early warning and assessment of drug trends.

In vitro and in vivo metabolic study of three new psychoactive β-keto-arylcyclohexylamines.

Journal of analytical toxicology May 20, 2024 Linhao Xu, Hui Yan, Yiling Tang et al. 3 citations

Since the 2000s, more new psychoactive substances have appeared on the illicit drug market. β-Keto-arylcyclohexylamine compounds, which have pharmacological roles in anesthesia, are increasingly used recreationally, but detailed toxicity data are lacking. Analyzing their metabolites can help forensic personnel determine whether someone has taken these illicit substances. This study examined the in vitro and in vivo metabolism of three such compounds: deschloro-N-ethyl-ketamine, fluoro-N-ethyl-ketamine, and bromoketamine. Using zebrafish and human liver microsomes, 49 metabolites were identified via liquid chromatography-high-resolution mass spectrometry. Hydroxy-deschloro-N-ethyl-ketamine, hydroxy-fluoro-N-ethyl-ketamine, and hydroxy-bromoketamine are recommended as biomarkers for documenting intake in clinical and forensic cases.

How to sample a seizure plant: the role of the visualization spatial distribution analysis of Lophophora williamsii as an example.

Forensic sciences research June 1, 2023 Jiaman Lin, Keming Yun, Qiran Sun et al. 2 citations

Mescaline is concentrated in the epidermal tissues and the meristematic tissues of the crown of Lophophora williamsii (peyote), as shown by a validated MALDI mass spectrometry imaging method. Low-temperature storage at -80°C, drying of flower samples, and cutting 40 μm thick sections at -20°C using gelatin as embedding medium are appropriate preparation conditions. Using DCTB as an auxiliary matrix and a laser intensity of 45 are favorable parameters for mescaline analysis. These findings provide a basis for determining the best sampling locations for mescaline in peyote and offer a reference for optimizing storage and preparation conditions for raw plant organs before MALDI detection.

Metabolism study of two phenethylamine - derived new psychoactive substances using in silico, in vivo, and in vitro approaches.

Archives of toxicology March 10, 2025 Yiling Tang, Linhao Xu, Zhenshuo Guo et al. 1 citation

Proscaline and methallylescaline are two phenylethylamine derivatives of the classic hallucinogen mescaline, classified as new psychoactive substances (NPS) not controlled by international drug conventions. Limited toxicity information has hindered their identification. Using high-resolution mass spectrometry with three complementary models—computational prediction, zebrafish (in vivo), and human liver microsomes (in vitro)—the study identified 7 proscaline metabolites and 11 methallylescaline metabolites for the first time. Hydroxylated and N-acetylated products were the major metabolites, enabling their selection as biomarkers for detecting intake of these two NPS over a relatively wide detection window.

Qualitative confirmation of 30 phencyclidine analogs in human blood and urine using GC-HRMS and a self-built library search.

Journal of chromatography. B, Analytical technologies in the biomedical and life sciences February 1, 2025 Zixuan Song, Zhenshuo Guo, Yiling Tang et al. 1 citation

A new high-throughput screening method using gas chromatography–high-resolution mass spectrometry (GC-HRMS) identifies 30 phencyclidine analogs in human blood and urine. After a simple extraction with ethyl ether and buffer, analytes are identified using a self-built library and reference spectra; isomers are differentiated by exact molecular mass and retention time. The method shows no interferences, recovery ranges from 30% to 123%, and detection limits from 0.05 to 5 ng/mL. Applied to 800 authentic forensic cases, it detected four analogs—2-F-2-oxo-PCE, 3-MeO-PCE, O-PCE, and 2-FDCK—demonstrating suitability for sensitive, fast high-throughput drug screening.

Concentrations of LSD, 2-oxo-3-hydroxy-LSD, and iso-LSD in hair segments of 18 drug abusers.

Forensic science international March 1, 2023 Jiaming Zheng, Xin Wang, Jiali Zhang et al. 1 citation

A new LC-MS/MS method was developed to simultaneously extract LSD, iso-LSD, 2-oxo-3-hydroxy-LSD, and 1-propionyl-LSD from hair samples. The method was applied to hair from 18 suspected LSD users. Segmental hair analysis showed LSD concentrations decreasing from the proximal to the distal end, while 1 P-LSD was not detected in any hair segments. The authors report concentrations of LSD and iso-LSD in human hair from 18 LSD users, but note that interpreting hair analysis results for LSD remains difficult.

Chiral analysis of ketamine enantiomers in human urine and hair: Application to authentic cases of ketamine use.

Journal of pharmaceutical and biomedical analysis August 15, 2025 Zhen Zhang, Yan Shi, Meiting Lin et al.

A UHPLC-MS/MS method was developed to separate and measure the two mirror-image forms (enantiomers) of ketamine in human urine and hair. After a deceased person used esketamine before death, only S-ketamine appeared in blood and urine, indicating that ketamine does not switch between its enantiomeric forms in the body. In 45 hair samples from ketamine abusers, the ratio of R-ketamine to S-ketamine ranged from 0.809 to 1.43, showing that illegal-market ketamine is mostly racemic (equal parts both enantiomers). A significant difference in this ratio was found between samples from China and Myanmar, likely due to regional variations in synthetic routes.