Determination of 13 potential anti-obesity agents in hair by dispersive liquid-liquid microextraction-assisted UHPLC-MS/MS.

As the adulteration of dietary supplements with synthetic drugs remains a prevalent issue, the inclusion of anti-obesity agents may pose health risks, potentially leading to central nervous system or cardiovascular diseases. However, surveillance studies on the use of anti-obesity agents by the Chinese population are limited. This study aims to establish an efficient and rapid hair pretreatment method using dispersive liquid-liquid microextraction (DLLME) combined with high-speed grinding and develop a sensitive and accurate analytical method employing ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for detecting 13 potential anti-obesity agents in hair samples. Herein, hair samples were washed sequentially with 0.1% sodium dodecyl sulfate (SDS), water and acetone, and then ground at high speed using 1 mL of an extraction solution (internal standard solution-n-butanol-1.2 mol/L Na2HPO4, pH10.0, 100:400:500, v/v/v for procaterol; internal standard solution-ethyl acetate-1.2 mol/L Na2HPO4, pH8.0, 100:300:600, v/v/v for other 12 anti-obesity agents) while simultaneously performing DLLME. The developed method successfully detected 13 anti-obesity agents within 11 min, including bambuterol, clenbuterol, ractopamine, clorprenaline, formoterol, salbutamol, terbutaline, procaterol, phentermine, bupropion, sibutramine, desmethyl sibutramine, and N,N-didesmethyl sibutramine, which improved the screening efficiency. The calibration curves exhibited good linearity of 0.025-5 ng/mg, achieving correlation coefficients of r ≥ 0.99. The lower limits of quantification (LLOQs) for the analytes were 0.025 ng/mg, demonstrating acceptable levels of accuracy and precision. Recovery rates ranged between 73.30% and 107.47% across the three concentrations of 0.075, 0.375, and 3.75 ng/mg. The validated method was successfully applied to 369 real cases and detected six analytes, including bambuterol, salbutamol, terbutaline, sibutramine, desmethyl sibutramine, and N,N-didesmethyl sibutramine. This method offers several advantages, including simple pretreatment, high extraction efficiency, rapid extraction, solvent economy, and pollution mitigation, making it highly suitable for large-scale surveillance of usage of added anti-obesity agents.

Quantitative determination of nitrous oxide in human blood by HS-GC-MS: forensic application of two fatal poisoning cases.

Nitrous oxide (N2O), also known as laughing gas, has a euphoric effect and is becoming increasingly popular as a recreational inhalant drug. Deaths caused by recreational nitrous oxide abuse are rare, but may still occur. Although some methods for the quantification of N2O by GC-MS have been reported, elimination of carbon dioxide interference and the choice of a suitable internal standard remain current limitations to accurate N2O quantification. Here, a validated method using headspace-gas chromatography-mass spectrometry (HS-GC-MS) is described that allows the quantification of N2O in human blood samples: sodium hydroxide is used to remove carbon dioxide, and n-pentane is chosen as a suitable internal standard. Collectively, the validation results show a good linear relationship of N2O in blood within the concentration range of 0.02 ∼ 0.5 mL/mL and an LOD of 0.005 mL/mL. Subsequent application of the validated method to two real mortality cases due to N2O intoxication provided reference values for blood concentrations in forensic cases. Other biological specimens (gaseous samples and tissues) of the deceased were also analyzed to demonstrate that the deaths were caused by asphyxia due to the inhalation of N2O.

Investigating alcohol consumption in China via wastewater-based epidemiology.

Alcohol abuse and addiction is a public health issue of global concern. Wastewater-based epidemiology (WBE) is a forceful and effective complementary tool for investigating chemical consumption. This study examined alcohol consumption in major cities of China via WBE and compared WBE estimates with other data sources. A simple and valid ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the determination of two alcohol metabolites, ethyl glucuronide (EtG) and ethyl sulfate (EtS) in wastewater. The optimized method was applied to 62 sewage samples collected from wastewater treatment plants (WWTPs) in 31 provincial capital cities across China in the fourth quarter of 2020. The methodology established in this study was validated with the lower limit of quantification (LLOQ) up to 0.1 µg/L, good linearity in the range of 0.1-50 µg/L, intra-day and inter-day precision less than 5.58% and 5.55%, respectively, and the recoveries of the extracts were higher than 97.14%. The consumption range of alcohol estimated via WBE was 6.09 ± 4.56 ethanol/person/day (EPD) in the capital cities of China. Alcohol consumption varies significantly between cities in China, with WBE estimating lower alcohol consumption than WHO and lower than foreign countries. Investing in alcohol consumption based on WBE has great potential to accurately and efficiently estimate alcohol consumption.

An antibacterial packaging film based on amylose starch with quaternary ammonium salt chitosan and its application for meat preservation.

A new generation of food packaging films is gradually replacing traditional plastic packaging films because of their biodegradability, safety, and some functional properties such as anti-bacterial and oxidant resistance. In the present work, an antibacterial packing film based on amylose starch and 2-hydroxypropyl-trimethylammonium chloride chitosan (HTCC) was prepared for meat preservation. The interfacial bonding mechanism between amylose, HTCC, and glutaraldehyde (GA) was determined experimentally and through molecular dynamics (MD) simulation. The macromolecular chains of amylose starch and HTCC became entangled via inter-molecular H-bonds and then cross-linked with GA via the Schiff base reaction. The interaction of amylose starch and HTCC improved the mechanical properties of the amylose films. Compared with the amylose films, the tensile strength and elongation at break of the optimal HTCC/amylose films reached to 16.13 MPa (an increase of 206.65 %) and 53.86 % (an increase of 109.49 %). The HTCC/amylose films were found to provide obvious bacteriostatic performance, a relatively low cytotoxicity, the lower transmittance in the UV region, and thus the ability to enhance the preservation of fresh meat. These excellent characteristics therefore suggest that HTCC/amylose films might be promising candidates for application in antibacterial food packaging films.

Low-Cytotoxicity, Broad-Spectrum Corn Starch-Based Antibacterial Particles that Inhibit Multidrug-Resistant Bacteria.

Antimicrobial resistance is a serious problem in biomedical applications that seriously increases the risk of medical failure. Therefore, developing highly efficient antibacterial agents that inhibit the growth of multidrug-resistant bacteria is a long-standing research goal. In this report, a low-cytotoxicity and highly efficient alternative to antibiotics was designed and prepared using edible corn starch as the scaffold and 2-hydroxypropyl-trimethylammonium chloride chitosan (HTCC) as the antimicrobial agent. The HTCC/starch particles were found to have a positively charged surface over a wide pH range and to possess broad-spectrum and highly efficient antimicrobial properties. These particles inhibited the growth of standard Gram-positive and Gram-negative bacteria from the China Pharmacopoeia and a clinical multidrug-resistant bacterial strain. Moreover, after treating the HTCC/starch particles with simulated gastric fluid (SGF, pH 1.2) for 4 h, the growth of clinical multidrug-resistant Escherichia coli (NT 2036) was inhibited effectively, indicating that these particles tolerate a gastric acid environment. Although the mass of SGF-treated HTCC/starch particles required to achieve similar antibacterial activity was ∼20-fold that of chloramphenicol or ampicillin, antibiotic-containing products require considerable amounts of pharmaceutical excipients to prepare. Therefore, the HTCC/starch particles described herein are potentially cost-effective alternatives to antibiotics that resolve the antimicrobial resistance issue, especially for inhibiting the growth of pathogenic intestinal bacteria.

Design and development of a lanthanide-labeled immunochromatographic strip for simultaneous detection of morphine, methamphetamine and ketamine in hair.

Colloidal gold immunoassay is the most widely used method in the field of drug detection. However, this method often has poor quantitative identification ability and low analytical sensitivity, which is not suitable for the analysis of hair poisoning ingredients. In order to solve these limitations, we developed an immunochromatographic test strip for simultaneously screening multiple drugs in this study. This hand-held test strip used fluorescent nanoparticles loaded with lanthanide chelates as the signal carrier of fluorescence reading, and conducted quantitative testing of various drugs based on the competitive immune reaction between the analyte and antigen. Under the optimal conditions, the competition curves of morphine (MOP), methamphetamine (MET) and ketamine (KET) were obtained on a single band. The detection limit (LOD) of this analytical method was 100-1000 times lower than that of colloidal gold test strips. The detection limits of MOP, MET and KET were 0.06 ng mL-1, 0.1 ng mL-1 and 1.0 ng mL-1, respectively. No cross-reaction was observed when morphine, methamphetamine and ketamine were tested simultaneously with this method. And 184 hair samples were tested simultaneously, and the detected amount was very close to the results of LC-MS. The immunochromatographic strip showed good stability in repeated tests, and the coefficient of variation was less than 15%. Fluorescence immunochromatography strips and handheld strip readers have the characteristics of portability, speed, ease of operation and high sensitivity, and may become powerful tools for screening drug abuse in hair in forensic medicine.

Hepatic retinaldehyde deficiency is involved in diabetes deterioration by enhancing PCK1- and G6PC-mediated gluconeogenesis.

Type 2 diabetes (T2D) is often accompanied with an induction of retinaldehyde dehydrogenase 1 (RALDH1 or ALDH1A1) expression and a consequent decrease in hepatic retinaldehyde (Rald) levels. However, the role of hepatic Rald deficiency in T2D progression remains unclear. In this study, we demonstrated that reversing T2D-mediated hepatic Rald deficiency by Rald or citral treatments, or liver-specific Raldh1 silencing substantially lowered fasting glycemia levels, inhibited hepatic glucogenesis, and downregulated phosphoenolpyruvate carboxykinase 1 (PCK1) and glucose-6-phosphatase (G6PC) expression in diabetic db/db mice. Fasting glycemia and Pck1/G6pc mRNA expression levels were strongly negatively correlated with hepatic Rald levels, indicating the involvement of hepatic Rald depletion in T2D deterioration. A similar result that liver-specific Raldh1 silencing improved glucose metabolism was also observed in high-fat diet-fed mice. In primary human hepatocytes and oleic acid-treated HepG2 cells, Rald or Rald + RALDH1 silencing resulted in decreased glucose production and downregulated PCK1/G6PC mRNA and protein expression. Mechanistically, Rald downregulated direct repeat 1-mediated PCK1 and G6PC expression by antagonizing retinoid X receptor α, as confirmed by luciferase reporter assays and molecular docking. These results highlight the link between hepatic Rald deficiency, glucose dyshomeostasis, and the progression of T2D, whilst also suggesting RALDH1 as a potential therapeutic target for T2D.

Preparation of poly(methacrylic acid-co-ethylene glycol dimethacrylate)-functionalized magnetic polydopamine nanoparticles for the extraction of six cannabinoids in wastewater followed by UHPLC-MS/MS.

Phytocannabinoids and their synthetic analogs (natural and synthetic cannabinoids) are illicit drugs that are widely abused worldwide. Wastewater-based epidemiology (WBE) is an objective approach for the estimation of population-level exposure to a wide range of substances, especially drugs of abuse. However, the concentrations of cannabinoids in wastewater are extremely low (frequently at the levels of nanograms per liter), and the existing pretreatment procedures for wastewater have the disadvantages of time-consumption or low extraction recoveries. This study aimed to propose a novel poly (methacrylic acid-co-ethylene glycol dimethacrylate)-functionalized polydopamine-coated Fe3O4 nanoparticle (Fe3O4@PDA@poly (MAA-co-EGDMA)) as an adsorbent, and provide a highly sensitive quantitative analytical technique for the detection of five synthetic cannabinoids (SCs: 5 F-EDMB-PINACA, FUB-APINACA, MDMB-4en-PINACA, MDMB-FUBINACA, and PB-22) and one cannabis-related human metabolite (THC-COOH) in wastewater. The magnetic adsorbents were fully characterized by transmission electron microscopy (TEM), infrared spectroscopy (IR), vibrating sample magnetometry (VSM) and X-ray photoelectron spectroscopy (XPS). Subsequently, an MSPE-UHPLC-MS/MS method was developed and validated for the determination of six trace analytes in wastewater. The validation results showed that the method has limits of quantification as low as 0.1-1.0 ng/L. Additionally, the recoveries ranged from 62.81 to 124.02%, and the relative standard deviations (RSDs) of intraday and interday precision were less than 15%. This MSPE-UHPLC-MS/MS method was successfully applied to real wastewater samples, and the whole analytical process of one sample from pretreatment to the obtained quantitative results was completed in less than 30 min. Thus, the proposed method based on Fe3O4@PDA@poly (MAA-co-EGDMA) is a convenient, rapid, sensitive and reliable method for the determination of trace psychoactive drugs in wastewater.

ATR-FTIR combined with machine learning for the fast non-targeted screening of new psychoactive substances.

Due to the diversity and fast evolution of new psychoactive substances (NPS), both public health and safety are threatened around the world. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), which serves as a simple and rapid technique for targeted NPS screening, is challenging with the rapid structural modifications of NPS. To achieve the fast non-targeted screening of NPS, six machine learning (ML) models were constructed to classify eight categories of NPS, including synthetic cannabinoids, synthetic cathinones, phenethylamines, fentanyl analogues, tryptamines, phencyclidine types, benzodiazepines, and "other substances" based on the 1099 IR spectra data items of 362 types of NPS collected by one desktop ATR-FTIR and two portable FTIR spectrometers. All these six ML classification models, including k-nearest neighbor (KNN), support vector machine (SVM), random forest (RF), extra trees (ET), voting, and artificial neural networks (ANNs) were trained through cross validation, and f1-scores of 0.87-1.00 were achieved. In addition, hierarchical cluster analysis (HCA) was performed on 100 synthetic cannabinoids with the most complex structural variation to investigate the structure-spectral property relationship, which leads to a summary of eight synthetic cannabinoid sub-categories with different "linked groups". ML models were also constructed to classify eight synthetic cannabinoid sub-categories. For the first time, this study developed six ML models, which were suitable for both desktop and portable spectrometers, to classify eight categories of NPS and eight synthetic cannabinoids sub-categories. These models can be applied for the fast, accurate, cost-effective, and on-site non-targeted screening of newly emerging NPS with no reference data available.

Nail analysis for the assessment of caffeine abuse in Northwest China: A population-based study.

Caffeine is the most widely consumed psychoactive agent worldwide and has the potential for abuse, but studies monitoring caffeine abuse in China are scarce. This study aims to estimate the prevalence of caffeine abuse in northwest China and investigate the correlation between caffeine and other drugs in hair and nails using an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Fingernail clippings were collected from 376 participants in northwest China to detect caffeine and 13 other illicit psychoactive drugs and their metabolites. Paired hair and nail samples were collected from 39 participants to investigate the correlation between caffeine and other drugs in hair and nails. The samples were decontaminated, pulverized, and extracted by a high-throughput nail sample preparation method and analyzed by UPLC-MS/MS. The results showed a risk of caffeine abuse in northwest China, with concentrations ranging from 0.43 to 10.6 ng/mg for healthy volunteers, 0.49-246 ng/mg for caffeine abusers, and 0.25-363 ng/mg for drug addicts in community rehabilitation centers. Caffeine was detected together with other illicit psychoactive drugs and their metabolites. Furthermore, positive detection correlations were found between hair and nail samples. This study provides a current perspective on caffeine abuse in northwest China and demonstrates the practical use of UPLC-MS/MS for the simultaneous detection of caffeine and 13 illicit psychoactive drugs and their metabolites in hair and nails. The results highlight the potential of nails as a supplementary matrix when hair samples are unavailable and emphasize the need for handling caffeine carefully given its potential for abuse.

Application of wastewater-based epidemiology to estimate the usage of beta-agonists in 31 cities in China.

The illegal use of beta-agonists could cause severe problems to human health. In this study, the usage of beta-agonists in 31 cities across China was estimated using wastewater-based epidemiology (WBE). The proposed method is based on solid-phase extraction (SPE) and LC-MS/MS and was developed and validated to determine the concentration of seven beta-agonists in wastewater. A population model based on cotinine (COT), NH4-N and the flow volume was constructed to estimate the population equivalents for different wastewater treatment plants (WWTPs). Clenbuterol and ractopamine are banned in China for both animal husbandry and medical use, but were nevertheless detected in some wastewater samples at rates of 6.2 % and 4.7 %, respectively (n = 339). The WBE-based consumption of clenbuterol and ractopamine were compared with the acceptable daily intake (ADI) and the health risks were assessed by their hazard quotients (0.26-6.62 for clenbuterol and 9.27 × 10-4-0.05 for ractopamine). Salbutamol, clorprenaline and terbutaline were observed in practically all wastewater samples at concentrations of up to several ng/L, whereas the formoterol and bambuterol concentrations were below the detection limit in all samples. Salbutamol consumption (7.35 ± 4.14 mg/1000 inh/day) was highest among the examined beta-agonists and varied regionally. Beta-agonist consumption based on WBE was higher in some cities than that based on medical survey data, indicating potential illegal use. These results show that WBE can be a straightforward and supplementary method for monitoring beta-agonist usage at the population level and spatially.

A comprehensive analytical strategy based on characteristic fragments to detect synthetic cannabinoid analogs in seized products and hair samples.

Synthetic cannabinoids, one of the most widely abused new psychoactive substances (NPS), are now placed under national control generally in China. Due to continuous modification of synthetic cannabinoid structure, an ongoing dilemma in the forensic laboratory is that newly emerging substances cannot be detected by established methods. Thus, the screening methods for simultaneous detection of known or unknown substances have become research hotspots. In this study, the ultra high performance liquid chromatography tandem triple quadrupole mass spectrometry (UPLC-QqQ-MS) with precursor ion scan (PIS) as acquisition mode was used for prescreening purposes of all possible synthetic cannabinoids-related substances. In detail, four common characteristic fragments, m/z of 144.0, 145.0, 135.1, and 109.0 corresponding to acylium-indole, acylium-indazole, adamantyl, and fluorobenzyl cation respectively, were selected for PIS mode, and their collision energies were optimized by 97 available synthetic cannabinoids standards with relevant structures. Those suspicious signals observed in the screening experiment were confirmed by ultra high performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) via high-resolution MS and MS2 data obtained by full scan (TOF MS) and product ion scan mode. After methodological validation, the integrated strategy established above was applied to the screening and identification of the seized e-liquids, herbal blends and hair samples, confirming the presence of multiple synthetic cannabinoids in these samples. In particular, a novel synthetic cannabinoid was identified as 4 F-ABUTINACA, for which no relevant high-resolution mass spectrometry (HRMS) data has been retrieved until now, making this study the first to report the cleavage pattern of this compound in electrospray ionization (ESI) mass spectrometry. In addition, four other suspected by-products of the synthetic cannabinoids were found in the herbal blends and e-liquids, and their possible structures were also deduced via the information from high-resolution mass spectra.

Application of the metal ions as potential population biomarkers for wastewater-based epidemiology: estimating tobacco consumption in Southern China.

Wastewater-based epidemiology (WBE) is an objective approach for the estimation of population-level exposure to a wide range of substances, in which the use of a population biomarker (PB) could significantly reduce back-calculation errors. Although some endogenous or exogenous compounds such as cotinine and other hormones have been developed as PBs, more PBs still need to be identified and evaluated. This study aimed to propose a novel method to estimate population parameters from the mass load of metal ion biomarkers in wastewater, and estimate the consumption of tobacco in 24 cities in Southern China using the developed method. Daily wastewater samples were collected from 234 wastewater treatment plants (WWTPs) in 24 cities in Southern China. Atomic absorption spectroscopy (AAS) was applied to determine the concentrations of common health-related metal ions in wastewater, including sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), iron (Fe), and zinc (Zn), and compared them with the daily mass load of cotinine corresponding to catchment populations. The concentrations of cotinine in wastewater samples were measured using liquid chromatography-tandem mass spectrometry. There were clear and strong correlations between the target metal ion equivalent population and census data. The correlation coefficients (R) were RK = 0.78, RNa = 0.66, RCa = 0.81, RMg = 0.77, and RFe = 0.69, at p < 0.01 and R2 > 0.6. Subsequently, the combination of WBE and metal ion PBs was used to estimate tobacco consumption. Daily consumption of nicotine was estimated to be approximately 1.76 ± 1.19 mg/d/capita, equivalent to an average of 13.0 ± 8.75 cigarettes/d being consumed by smokers. The data on tobacco consumption in this study were consistent with those in traditional surveys in Southern China. The metal ion potassium is an appropriate PB for reflecting the real-time population and could be used to evaluate the tobacco consumption in WBE study.

Bile duct ligation differently regulates protein expressions of organic cation transporters in intestine, liver and kidney of rats through activation of farnesoid X receptor by cholate and bilirubin.

Body is equipped with organic cation transporters (OCTs). These OCTs mediate drug transport and are also involved in some disease process. We aimed to investigate whether liver failure alters intestinal, hepatic and renal Oct expressions using bile duct ligation (BDL) rats. Pharmacokinetic analysis demonstrates that BDL decreases plasma metformin exposure, associated with decreased intestinal absorption and increased urinary excretion. Western blot shows that BDL significantly downregulates intestinal Oct2 and hepatic Oct1 but upregulates renal and hepatic Oct2. In vitro cell experiments show that chenodeoxycholic acid (CDCA), bilirubin and farnesoid X receptor (FXR) agonist GW4064 increase OCT2/Oct2 but decrease OCT1/Oct1, which are remarkably attenuated by glycine-ß-muricholic acid and silencing FXR. Significantly lowered intestinal CDCA and increased plasma bilirubin levels contribute to different Octs regulation by BDL, which are confirmed using CDCA-treated and bilirubin-treated rats. A disease-based physiologically based pharmacokinetic model characterizing intestinal, hepatic and renal Octs was successfully developed to predict metformin pharmacokinetics in rats. In conclusion, BDL remarkably downregulates expressions of intestinal Oct2 and hepatic Oct1 protein while upregulates expressions of renal and hepatic Oct2 protein in rats, finally, decreasing plasma exposure and impairing hypoglycemic effects of metformin. BDL differently regulates Oct expressions via Fxr activation by CDCA and bilirubin.

Machine Learning-Assisted Rapid Screening of Four Types of New Psychoactive Substances in Drug Seizures.

Over the past few years, new psychoactive substances (NPS) have become a global health and social problem because of their wide variety, constant structural renewal, vague legal definitions, and rapid adaptation to legal restrictions. The rapid structural modifications of NPS have posed significant challenges for the screening and identification of these new substances using traditional mass spectrometric techniques based on reference substances or a mass spectral database. Here, we propose supervised machine learning (ML) classification models such as k-nearest neighbors, support vector machine, random forest, and multigrained cascade forest for the rapid screening of NPS using mass spectrometric data. This approach utilizes ML methods to learn the statistical probability distributions of mass spectral data for NPS and non-NPS. Four classification ML models were generated and evaluated using a data set comprising 567 LC-MS and 732 GC-MS spectra. Through cross validation, we achieved an F1 score of 0.35-0.97. These algorithms were applied in conjunction with mass spectrometry techniques for the detection of six seizures including electronic cigarette oil and suspected powdered substances netted in drug trafficking cases. The models provided warning signals for synthetic cannabinoids, synthetic cathinones, and fentanyl. Thus, an early warning system was successfully established, which provided a useful method for reliable and effective identifications of unknown NPS.

Estimating the prevalence of hypertension in 164 cities in China by wastewater-based epidemiology.

Hypertension is the most common chronic non-infectious disease and a severe problem for public health in China. There were 244.5 million people aged over 18 years in China who had hypertension in 2015, and hypertension-related death accounted for more than 25 % of all causes of death in China every year. To monitor the hypertension prevalence in near real-time, a wastewater-based epidemiology (WBE) approach by using metoprolol acid as a biomarker was conducted in 164 cities in China. LC-MS/MS was utilized to quantify metoprolol acid in sewage, and satisfactory method validation results were achieved. The average concentration of metoprolol acid in sewage was 943.1 ± 671.1 ng/L, and the back-calculated consumption of metoprolol based on metoprolol acid was 932.0 ± 390.5 mg/day/1000inh on average, ranging from 76.7 to 3275.7 mg/day/1000inh. The prevalence of metoprolol was estimated to be 0.83 % ± 0.35 %, and the estimated hypertension prevalence in the population aged over 15 years was ultimately assessed to be 28.56 % ± 10.44 % ranging from 14.28 % to 44.28 % and was consistent with the China Hypertension Survey result of 27.9 %. This research demonstrated that estimating hypertension prevalence by WBE with metoprolol acid as a biomarker is feasible in Chinese cities.

Simultaneous quantification of 106 drugs or their metabolites in nail samples by UPLC-MS/MS with high-throughput sample preparation: Application to 294 real cases.

The nail is an alternative matrix to complement hair analysis in proving drug intake over several months in forensic toxicology investigations. However, because of the high hardness and toughness of nails, the existing pretreatment procedures for nails have the disadvantages of either a high degree of time consumption (from hours to days), or low extraction recoveries. This study aims to propose a high-throughput nail sample preparation method and provide a quantitative analytical method for 106 drugs and their metabolites present in nail. We developed cryogenic grinding, coupled with high-speed grinding in the extraction solvent method, which could improve the extraction recovery by thoroughly destroying the nail keratin for approximately 18 min. Subsequently, an ultra-high-performance liquid chromatography-tandem mass spectrometry method was developed for the identification and quantification of 34 synthetic cannabinoids, 26 fentanyls, 18 synthetic cathinones, 10 phenylethylamines, eight opioids, three phencyclidine, two tryptamines, two piperazine, cocaine, benzoylecgonine, and tetrahydrocannabinol (THC). Nail samples were collected from people with a history of drug abuse from five different regions of China. The analysis of 294 authentic samples resulted in 213 detected samples, and showed a broad concentration range including 5.04-67.26 pg/mg for nine synthetic cannabinoids, 109.29-250.29 pg/mg for a synthetic cathinone, 5.06-434291 pg/mg for four phenylethylamines, 5.06-464278 pg/mg for three phencyclidine, 5.50-192195 pg/mg for six opioids, 19.44-36.11 pg/mg for cocaine, and 50.53 pg/mg for THC in nail. Furthermore, up to 10 different compounds were detected in a single nail sample. This nail analysis method serves as a useful tool for the large-scale surveillance of illicit drugs abuse.

Preclinical Drug Pharmacokinetic, Tissue Distribution and Excretion Profiles of the Novel Limonin Derivate HY-071085 as an Anti-Inflammatory and Analgesic Candidate in Rats and Beagle Dogs.

Limonin is one of the research hotspots in natural drug development. However, its low solubility in water leads to poor oral bioavailability, discouraging the further study of its potential as a candidate compound. In order to overcome this limitation, and to enhance its biological activities, a novel limonin derivative-HY-071085-was synthesized by structural modification, and has exhibited strong anti-inflammatory and analgesic activity. In order to achieve a thorough understanding of the biological actions of HY-071085 in vivo, this study evaluated the pharmacokinetics and bioavailability of HY-071085 in rats and beagle dogs, and the distribution and excretion in rats. Using ultra-high-performance liquid chromatography-tandem mass spectrometry, the kinetic profiles of HY-071085 in the plasma of healthy rats and beagle dogs after a single gavage, repeated gavages and the intravenous injection of HY-071085 were studied. The tissue distribution (heart, liver, spleen, lung, kidney, gastric tissue, intestine, brain, skin, testis, ovary and womb) and excretion of HY-071085 were also studied. These results showed that HY-071085 has nonlinear dynamic characteristics in rat and beagle dog plasma. It was found that the plasma concentrations of HY-071085 in female rats were significantly higher than those in male rats after a single oral administration. There were gender differences in the kinetic behavior of HY-071085 in rats; however, there was no difference identified in dogs. HY-071085 was mainly eliminated as metabolites in rats, and was distributed in most of the tissues except the brain, with the highest content being in the gastric tissue and intestinal arease, followed by the liver, spleen, fat, lung, kidney, ovary and heart. The bioavailability of HY-071085 in male and female rats was 2.8% and 10.8%, respectively, and was about 13.1% in beagle dogs. The plasma protein binding rate of HY-071085 in rats, beagle dogs and humans ranged from 32.9% to 100%, with obvious species differences. In conclusion, our study provides useful information regarding the absorption, distribution and excretion of HY-071085, which will provide a good base for the study of the mechanism of its biological effects.

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.

UPLC-MS/MS method for the simultaneous quantification of caffeine and illicit psychoactive drugs in hair using a single-step high-speed grinding extraction - Insights into a cut-off value for caffeine abuse.

Caffeine is a commonly consumed psychoactive substance whose addictive potential has long been reported. Excessive caffeine intake may lead to severe health damage or drug addiction problems; however, studies on the surveillance of caffeine abuse by the Chinese population are lacking. This study aimed to propose a concentration value for caffeine based on hair analysis to distinguish excessive intake from normal consumption, and provide an analytical tool for forensic toxicology investigations of caffeine and other frequently abused drugs. A sensitive and accurate ultra-high performance liquid chromatography-tandem mass spectrometry method was developed to detect caffeine and 13 illicit drugs and their metabolites in hair. Thereafter, this method was employed to test 479 real samples. Briefly, the hair samples were washed with water and acetone, and subsequently extracted by one-step high-speed grinding with acetonitrile-buffer solution. The lower limit of quantifications of 0.05 ng/mg for caffeine and THC, and 0.005 ng/mg for others, were achieved for all substances. The results revealed a mean caffeine concentration of 0.78 (range 0.008-3.5 ng/mg) based on 24 healthy volunteers, 55.0 (range 3.07-292.2 ng/mg) based on 52 self-reported caffeine abuse participants, and 5.78 (range 0-140.34 ng/mg) based on 403 drug addicts. The mean caffeine concentration in hair from self-reported caffeine abusers was 70-fold higher than that in hair from healthy volunteers. A tentative cut-off level of 5.5 ng/mg as an indicator of excessive caffeine consumption was developed based on receiver operating characteristic analysis. Additionally, the assessment of 403 hair samples from drug addicts indicated that illicit drug abusers had potential for caffeine abuse, especially polydrug users. This hair analysis method serves as a useful tool for the large-scale surveillance of caffeine and illicit drug abuse.