In recent years, the types and quantities of fentanyl analogs have increased rapidly. It has become a hotspot in the illicit drug control field of how to quickly identify novel fentanyl analogs and to shorten the blank regulatory period. At present, the identification methods of fentanyl analogs that have been developed mostly rely on reference materials to target fentanyl analogs or their metabolites with known chemical structures, but these methods face challenges when analyzing new compounds with unknown structures. In recent years, emerging machine learning technology can quickly and automatically extract valuable features from massive data, which provides inspiration for the non-targeted screening of fentanyl analogs. For example, the wide application of instruments like Raman spectroscopy, nuclear magnetic resonance spectroscopy, high resolution mass spectrometry, and other instruments can maximize the mining of the characteristic data related to fentanyl analogs in samples. Combining this data with an appropriate machine learning model, researchers may create a variety of high-performance non-targeted fentanyl identification methods. This paper reviews the recent research on the application of machine learning assisted non-targeted screening strategy for the identification of fentanyl analogs, and looks forward to the future development trend in this field.
Fentanyl ; Substance Abuse Detection/methods* ; Mass Spectrometry/methods* ; Illicit Drugs/analysis*

Objective To establish accurate and rapid methods to identify four new synthetic cannabinoids （JWH-203, JWH-122, 5F-APINACA and AB-CHMINACA） in blood samples. Methods The whole blood samples were extracted by acetonitrile and methanol, screened by gas chromatography-mass spectrometry （GC-MS） then confirmed by liquid chromatography-tandem mass spectrometry （LC-MS/MS） method, and multiple reaction monitoring （MRM） mode was used for quantitative analysis. Results The GC-MS method needed 21 min to complete the analysis, while the LC-MS/MS method needed 5 min. The AB-CHMINACA, JWH-203, 5F-APINACA and JWH-122 all used quasi molecular ion peak as a parent ion. The precursor-product ion combinations were m/z 357.4→312.2, m/z 340.2→125.0, m/z 384.1→135.1 and m/z 356.4→169.2. The four synthetic cannabinoids in blood samples had good linearity in the 1-250 ng/mL mass concentration range （r>0.99）. The limits of detection （LODs） were in the range of 0.1-0.5 ng/mL, the recovery rate was 85.4%-95.2%, the RSD less than 10.0%, and the matrix effect was 80.3%-92.8%. Conclusion The GC-MS and LC-MS/MS chromatographic behaviors and mass spectrometry analysis information of four synthetic cannabinoids were obtained in this study, and the possible causes of differences in chromatographic behaviors were discussed preliminarily. Therefore this study has a suggestive effect on judging the development trend of synthetic cannabinoids. This method can be used for rapid identification of four synthetic cannabinoids in blood, which can provide reference for identification of new synthetic cannabinoids when they are proliferating at present.
Blood Chemical Analysis/methods* ; Cannabinoids/blood* ; Chromatography, Liquid ; Humans ; Limit of Detection ; Substance Abuse Detection/methods* ; Tandem Mass Spectrometry

Although doping with growth hormone (GH) is banned, there is anecdotal evidence that it is widely abused. GH is reportedly used often in combination with anabolic steroids at high doses for several months. Development of a robust test for GH has been challenging because recombinant human 22 kDa (22K) GH used in doping is indistinguishable analytically from endogenous GH and there are wide physiological fluctuations in circulating GH concentrations. One approach to GH testing is based on measurement of different circulating GH isoforms using immunoassays that differentiate between 22K and other GH isoforms. Administration of 22K GH results in a change in its abundance relative to other endogenous pituitary GH isoforms. The differential isoform method has been implemented; however, its utility is limited because of the short window of opportunity of detection. The second approach, which will extend the window of opportunity of detection, is based on the detection of increased levels of circulating GH-responsive proteins, such as insulin-like growth factor (IGF) axis and collagen peptides. Age and gender are the major determinants of variability for IGF-I and the collagen markers; therefore, a test based on these markers must take age into account for men and women. Extensive data is now available that validates the GH-responsive marker approach and implementation is now largely dependent on establishing an assured supply of standardized assays. Future directions will include more widespread implementation of both approaches by the World Anti-Doping Agency, possible use of other platforms for measurement and an athlete's passport to establish individual reference levels for biological parameters such as GH-responsive markers. Novel approaches include gene expression and proteomic profiling.
Doping in Sports ; Growth Hormone ; administration & dosage ; Humans ; Substance Abuse Detection ; methods

OBJECTIVES: To establish a combined high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) method to detect the synthetic cannabinoid CUMYL-PEGACLONE in e-cigarette oil and hair. METHODS: HPLC-MS/MS and GC-MS were used to establish the detection method of CUMYL-PEGACLONE, and the hair of drug-involved persons and the seized e-cigarette oil were detected. RESULTS: The main mass spectrometry characteristic ions m/z of CUMYL-PEGACLONE measured by GC-MS were 91, 179, 197, 254 and 372. CUMYL-PEGACLONE had a good linear relationship in the mass concentration range of 2-50 ng/mL, and the linear correlation coefficient (r) was greater than 0.99. The limit of detection (LOD) of CUMYL-PEGACLONE in hair was 0.01 ng/mg, and the limit of quantitation (LOQ) was 0.02 ng/mg. The LOD of CUMYL-PEGACLONE in e-cigarette oil was 1 ng/mg, and the LOQ was 2 ng/mg. The average recoveries of CUMYL-PEGACLONE under the attempt at high, intermediate and low levels in blank human hair and e-cigarette oil matrix were 98.2%-132.4% and 93.5%-110.6%, and the intraday and intraday precision were 1.2%-12.9% and 0.7%-2.9%. CUMYL-PEGACLONE was detected in the hair of 15 drug-involved persons. Except for 1 person who was lower than LOQ, the concentration of CUMYL-PEGACLONE in the hair of other 14 persons was 0.035-0.563 ng/mg. The mass fraction of CUMYL-PEGACLONE in 2 e-cigarette oil were 0.17% and 0.21%, respectively. CONCLUSIONS The established HPLC-MS/MS and GC-MS methods are applied to the detection of HPLC-MS/MS in drug-related cases, which provides strong evidence support for the handling authority to quickly investigate these cases, and also provides a reference for the identification of such substances in future.
Humans ; Illicit Drugs/analysis* ; Tandem Mass Spectrometry ; Electronic Nicotine Delivery Systems ; Cannabinoids ; Hair/chemistry* ; Limit of Detection ; Substance Abuse Detection/methods*

Saliva is an easily collected body fluid and has simple composition. Some drugs concentrations in saliva can reflect their blood level. This paper analyzes the mechanisms of drug transfer from blood into saliva and the influencing factors, reviews the methods of sample collection, preparation, analysis of the abused drugs in saliva, and the relationship between abused drugs content in saliva and in blood. We believe that saliva is a valuable sample in clinic and forensic medicine. It is important in forensic science field to estimate abused drugs concentrations in blood by via their saliva concentrations.
Forensic Medicine/methods* ; Humans ; Illicit Drugs/pharmacokinetics* ; Saliva/chemistry* ; Specimen Handling/methods* ; Substance Abuse Detection/methods* ; Substance-Related Disorders/prevention & control*

OBJECTIVE: To propose a method for simultaneous determination of codeine(COD), 6-monoacetyl-morphine (6-MAM), morphine (MOR), morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) in human urine by ultra performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). METHODS: After precipitation of protein by acetonitrile, the urine samples, with added the morphine-d3 (MOR-d3) and morphine-3-Glucuronide-d3 (M3G-d3) as internal standards, were pre-treated by Sirocco protein precipitation plate, and then analyzed by UPLC-MS/MS. RESULTS: The limit of detection was 0.2 ng/mL for both COD and MAM, the limit of quantitation was 0.5 ng/mL for both COD and MAM. The limit of detection was 0.5 ng/mL for MOR, M3G and M6G, the limit of quantitation was 1 ng/mL for them. The linear correlation coefficients were not less than 0.9997, both the inter-day and intra-day precisions were less than 10%, the recoveries were in the range of 70.0% to 98.3%, the matrix effects were about 50.5% to 99.0%. CONCLUSION This proposed method is simple, rapid and accurate, it could be applied in forensic toxicological analysis.
Chromatography, Liquid/methods* ; Codeine/urine* ; Humans ; Limit of Detection ; Morphine/urine* ; Morphine Derivatives/urine* ; Reproducibility of Results ; Sensitivity and Specificity ; Substance Abuse Detection/methods* ; Tandem Mass Spectrometry/methods*

Recently the cases after drinking are increasing, but the systematic studys on ethanol content in vivo and correlative problems are still absent. According to the measured results of ethanol content in vivo, ethanol metabolic distributed rules, mechanisms of ethanol toxicological effect and its production in vivo, this study analysed systematically the time after drinking, total quantity of absorbed ethanol, psychological situations, behavioral dominated ability, death causes and manners in order to find out the implied forensic medical information and provide the reference for colleague.
Alcohol Drinking/metabolism* ; Alcohol-Induced Disorders ; Ethanol/metabolism* ; Forensic Medicine ; Humans ; Postmortem Changes ; Substance Abuse Detection/methods* ; Time Factors

OBJECTIVES: To identify the new designer drugs which are totally unknown and not in the routine testing list by the technologies such as high-resolution mass spectrometry in drug facilitated sexual assault, in order to solve the problem in actual cases. METHODS: The milky fluid from an actual case was extracted and analyzed using LC-QE, ¹H-NMR and GC-MS, respectively. The accurate masses and cluster ions isotope patterns of unknown compound were obtained by LC-QE. The molecular formula was confirmed as C₁₆H₁₂C₂N₂O based on the protons number of ¹H-NMR. The isomers diclazepam and 4-chlorodiazepam were separated and detected with GC-MS. RESULTS: The new designer benzodiazepine as diclazepam in the milky fluid was identified. The results provided direct evidence for the investigation and qualitative analysis of such cases. CONCLUSIONS The combined application of various methods, including LC-QE, ¹H-NMR and GC-MS, can be used to detect unknown new psychoactive substances.
Benzodiazepines/chemistry* ; Benzodiazepinones ; Chromatography, Liquid/methods* ; Designer Drugs/chemistry* ; Female ; Gas Chromatography-Mass Spectrometry/methods* ; Humans ; Male ; Mass Spectrometry/methods* ; Sex Offenses ; Substance Abuse Detection/methods* ; Toxicology/methods*

OBJECTIVE: To develop a method for determining ethyl glucuronide (EtG) in blood and urine by liquid chromatograph coupled with tandem mass spectrometer (LC-MS/MS). METHODS: After blood and urine de-proteined by acetonitrile, the supernate obtained from a centrifuge was analyzed by LC-MS/MS. RESULTS: Determination limit of EtG in both blood and urine was 0.05 pg/mL, with a linear range of 0.10-5.00 microg/mL (r > 0.999). Accuracy in both matrixes was 95%-109%. Inter- and intra-day RSD were less than 12%. The method showed an excellent performance when it was used to analyze authentic blood and urine samples for EtG. CONCLUSION The method is capable for blood and urine EtG analysis.
Alcoholism/urine* ; Biomarkers/urine* ; Chromatography, Liquid/methods* ; Ethanol/metabolism* ; Forensic Toxicology/methods* ; Glucuronates/urine* ; Humans ; Reproducibility of Results ; Sensitivity and Specificity ; Substance Abuse Detection/methods* ; Tandem Mass Spectrometry/methods*

The abuse of ketamine has gained popularity in recent years. It is important to develop rapid and accurate methods to determine ketamine and its metabolites in biological samples. The metabolites of ketamine are norketamine and dehydronorketamine in vivo. At present, there are blood, urine, hair and so on as specimens for detection, while the methods include GC, GC/MS, HPLC, LC/MS, HPCE etc. In this paper, these methods used for ketamine and its metabolites were reviewed in order to provide some preference for the study in relative fields.
Anesthetics, Dissociative/chemistry* ; Chromatography, High Pressure Liquid/methods* ; Forensic Medicine ; Gas Chromatography-Mass Spectrometry/methods* ; Hair/chemistry* ; Humans ; Ketamine/metabolism* ; Sensitivity and Specificity ; Substance Abuse Detection/methods*