Herbicides are a kind of chemical or biological agents that can effectively destroy or inhibit weed growth. Because of the widespread and frequent use of herbicides, herbicide poisonings have often been reported. At present, the main species reported to have caused poisoning are paraquat, diquat, glyphosate, and glufosinate. The main instrumental analysis method is LC-MS. This paper reviews the research progress on analysis methods of common herbicides in biological material and their application, summarizes the sample pretreatment and instrumental analysis situation of qualitative and quantitative analysis of herbicides in biological material, and collects test data of actual poisoning cases, to provide reference for clinical diagnosis and treatment and forensic identification of herbicide poisoning.
Chromatography, Liquid ; Herbicides ; Mass Spectrometry ; Paraquat

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) combines the advantages of high separation ability of chromatography and high selectivity, specificity and sensitivity of mass spectrometry, making it one of the most vibrant new technologies in the field of clinical testing. However, the analytical performance is often limited by the characteristics of the sample to be measured. Due to the limited anti-contamination capability of the mass spectrometer, biological samples need to be properly pre-processed to effectively improve the detection performance and achieve accurate detection. The main function of pre-treatment is to selectively separate the target analyte from the biological matrix to reduce interference from other matrix components. At the same time, the target analytes can be concentrated and enriched to improve the analytical sensitivity. At present, there are many kinds of clinical sample pre-treatment methods, and several methods are time-consuming and cumbersome, which brings difficulties to laboratory personnel in method selection, development and standardized operation. Therefore, the purpose of this consensus is to provide guidance for the establishment of laboratory methods and facilitate the standardized development of clinical mass spectrometry measurement.
Humans ; Chromatography, Liquid ; Consensus ; Tandem Mass Spectrometry

Objective To study the qualitative analysis strategy for unknown synthetic cannabinoid in the suspicious herbal product when no reference substance is available. Methods The synthetic cannabinoid in herbal blend was extracted with methanol. The extract was concentrated by rotary evaporator and separated and purified by preparative liquid chromatography, to obtain high purity synthetic cannabinoid sample. Gas chromatography-mass spectrometry （GC-MS）, ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry （UPLC-QTOF-MS） and nuclear magnetic resonance （NMR） were used to determine the structure of the prepared compound. Results High purity unknown sample （10 mg） was obtained by preparative liquid chromatography. The sample was analyzed by GC-MS, UPLC-TOF-MS and NMR, and through spectrum analysis, the unknown synthetic cannabinoid was determined as 5F-EDMB-PICA. Conclusion The method to extract unknown synthetic cannabinoid from low content herbal products by preparative liquid chromatography was established, and the structure of the unknown sample was identified by comprehensive use of GC-MS, UPLC-QTOF-MS and NMR. The information will assist forensic laboratories in identifying this substance or other compounds with similar structures in their casework.
Cannabinoids ; Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Gas Chromatography-Mass Spectrometry ; Mass Spectrometry

Objective To study the identification method for 4'-F-4-methylaminorex （4'-F-4-MAR） in samples without reference substance. Methods Gas chromatography-mass spectrometry （GC-MS）, ultra-high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry （UPLC-QTOF-MS）, nuclear magnetic resonance （NMR） and Fourier transform infrared （FTIR） were comprehensively used for the structure identification of 4'-F-4-MAR in samples. Results Under the positive electrospray ionization （ESI⁺） mode, quasi-molecular ion in the first order mass spectrometry of the unknown compound was 195.092 6 and its molecular formula was inferred to be C₁₀H₁₁FN₂O. The fragment ions in the mass spectrometry of the unknown compound were compared with the related fragment ions of 4,4'-dimethylaminorex （4,4'-DMAR） in literature. It was found that the main fragment ions of the unknown compound were all 4 bigger than the corresponding fragment ions of 4,4'-DMAR. Therefore, the unknown compound was inferred to be a 4,4'-DMAR analogue with a methyl substituted by a fluorine in the benzene ring. The equivalent protons at δ=7.30 and δ=7.06 in ¹H-nuclear magnetic resonance （¹H-NMR） spectra and the characteristic spin-spin coupling constants （¹J_C-F=245.2 Hz, ²J_C-F=21.3 Hz, ³J_C-F=8.1 Hz） for ¹³C-¹⁹F interactions in carbon spectra, further proved that the fluorine substituted methyl at the para-position of the benzene ring. Finally, the unknown compound was determined as 4'-F-4-MAR. Conclusion A method that comprehensively used the identification materials 4'-F-4-MAR in GC-MS, UPLC-QTOF-MS, NMR and FTIR is established and the fragmentation mechanism of fragmentation ions of 4'-F-4-MAR created under the two modes -- electron impact （EI） and electrospray ionization under collision induced dissociation （ESI-CID） is deduced. The information will assist forensic science laboratories in identifying this compound or other substances with similar structure in their case work.
Aminorex ; Chromatography, High Pressure Liquid ; Gas Chromatography-Mass Spectrometry ; Mass Spectrometry ; Nitroimidazoles ; Spectrometry, Mass, Electrospray Ionization

Male ; Humans ; Liquid Chromatography-Mass Spectrometry ; Chromatography, Liquid ; Tandem Mass Spectrometry ; Varicocele/diagnosis* ; Biomarkers

OBJECTIVES: To establish a method for the simultaneous quantitative analysis of etomidate and its metabolite etomidate acid in blood, and to discuss its application value in actual cases. METHODS: Acetonitrile precipitate protein method was used, and C₁₈ column was selected. Gradient elution was performed with acetonitrile and 5 mmol/L ammonium acetate within 6 min. Electrospray ionization source in positive ion mode was used. The internal standard etomidate acid-d₅ was obtained by etomidate-d₅ alkaline hydrolysis reaction. Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used for quantitative analysis. The methodological verification was conducted. RESULTS: Etomidate and etomidate acid in blood showed good linear relationship in the quantitative linear range (r>0.999), with the lower limit of quantification was 2.5 ng/mL and 7.5 ng/mL, respectively. The accuracy, precision, recovery rate, and matrix effect of the method met the professional verification standards. The practical application results showed that etomidate and etomidate acid could be detected in the blood of the abusers, and their mass concentrations ranged from 17.24 to 379.93 ng/mL. CONCLUSIONS The method established in this study can simultaneously quantify etomidate and etomidate acid in blood, which is simple and convenient to operate with accuracy. It can meet the detection needs of actual cases and provide technical support for law enforcement to crack down on etomidate abuse.
Chromatography, High Pressure Liquid/methods* ; Chromatography, Liquid ; Etomidate ; Tandem Mass Spectrometry/methods* ; Liquid Chromatography-Mass Spectrometry ; Acetonitriles

Objective To establish an ion chromatography method for the salt form determination of new psychoactive substances （NPS）. Methods The method of conducting qualitative and quantitative analysis of six types of organic acid ions （acetate ion, tartrate ion, maleate ion, oxalate ion, fumarate ion, citrate ion） and five types of inorganic anions （fluoride ion, chloride ion, nitrate ion, sulfate ion, phosphate ion） in NPS sample by ion chromatography was developed. The salt forms of 222 seized NPS samples （103 samples with synthetic cannabinoids, 81 samples with cathinones, 44 samples with phenylethylamines, 12 samples with tryptamines, 7 samples with phencyclidines, 6 samples with piperazines, 2 samples with aminoindenes, 26 samples with fentanyls and 43 samples with other types of NPS） were analyzed by this method. Results Each anion had good linearity in the corresponding linear range, the correlation coefficients （r） were greater than 0.999, the limits of detection were 0.01-0.05 mg/L, and the limits of quantitative were 0.1-0.5 mg/L. Except that 5F-BEPIRAPIM was hydrochloride, the salt forms of the other 102 synthetic cannabinoids were all base. The salt form of 81 cathinone samples, 44 phenylethylamine samples, 7 phencyclidine samples and 2 aminoindene samples were all hydrochloride. The salt forms of tryptamine samples included base, hydrochloride, fumarate and oxalate. The salt forms of piperazine samples included base and hydrochloride. The salt forms of fentanyl samples and samples of other types included base, hydrochloride and citrate. Conclusion Ion chromatography is a simple, accurate and efficient method for determining the salt form of NPS samples, which makes the qualitative and quantitative conclusions of NPS more scientific and rigorous.
Chromatography, Liquid ; Gas Chromatography-Mass Spectrometry ; Ions ; Psychotropic Drugs/chemistry*

In this study, ultra-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry(UPLC-Q-TOF-MS) and gas chromatography-mass spectrometry(GC-MS) were combined with non-targeted metabonomic analysis based on multivariate statistics analysis, and the content of five indicative components in nardosinone was determined and compared by UPLC. The main chemical components of Nardostachyos Radix et Rhizoma with imitative wild cultivation and wild Nardostachyos Radix et Rhizoma were comprehensively analyzed. The results of multivariate statistical analysis based on liquid chromatography-mass spectrometry(LC-MS) and GC-MS were consistent. G1 and G2 of the imitative wild cultivation group and G8-G19 of the wild group were clustered into category 1, while G7 of the wild group and G3-G6 of the imitative wild cultivation group were clustered into category 2. After removing the outlier data of G1, G2, and G7, G3-G6 of the imitative wild cultivation group were clustered into one category, and G8-G19 of the wild group were clustered into the other category. Twenty-six chemical components were identified according to the positive and negative ion modes detected by LC-MS. The content of five indicative components(VIP>1.5) was determined using UPLC, revealing that chlorogenic acid, isochlorogenic acid A, isochlorogenic acid C, linarin, nardosinone, and total content in the imitative wild cultivation group were 1.85, 1.52, 1.26, 0.90, 2.93, and 2.56 times those in the wild group, respectively. OPLS-DA based on GC-MS obtained 10 diffe-rential peaks. Among them, the relative content of α-humulene and aristolene in the imitative wild cultivation group were extremely significantly(P<0.01) and significantly(P<0.05) higher than that in the wild group, while the relative content of 7 components such as 5,6-epoxy-3-hydroxy-7-megastigmen-9-one, γ-eudesmol, and juniper camphor and 12-isopropyl-1,5,9-trimethyl-4,8,13-cyclotetrade-catriene-1,3-diol was extremely significantly(P<0.01) and significantly(P<0.05) lower than that in the wild group, respectively. Therefore, the main chemical components of the imitative wild cultivation group and wild group were basically the same. However, the content of non-volatile components in the imitative wild cultivation group was higher than that in the wild group, and the content of some volatile components was opposite. This study provides scientific data for the comprehensive evaluation of the quality of Nardostachyos Radix et Rhizoma with imitative wild cultivation and wild Nardostachyos Radix et Rhizoma.
Gas Chromatography-Mass Spectrometry ; Chromatography, Liquid ; Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal/chemistry* ; Tandem Mass Spectrometry

A UHPLC-Q Exactive Orbitrap MS method was used to analyze the chemical constituents of the classical prescription Qianghuo Shengshi Standard Decoction(QHSS). UHPL conditions were as follows: Waters~(TM) UPLC~(TM) HSS T3 C_(18) column(2.1 mm×100 mm, 1.7 μm) and mobile phase of acetonitrile-0.1% formic acid aqueous solution. Mass spectrometry data of QHSS, each herb extract, and negative sample were collected in both positive and negative ion modes. The chemical constituents of QHSS were identified or tentatively identified based on the accurate molecular weight, retention time, MS fragmentation, comparison with reference substances, and literature reports. A total of 141 compounds were identified, including 18 amino acids, oligosaccharides, oligopeptides, and their derivatives, 19 phenolic acids, 44 coumarins, 18 flavonoids and chromones, 13 saponins, 17 phthalides, and 12 other components. This study comprehensively characterized the chemical constituents of QHSS, laying an experimental basis for the in-depth research on the material basis and quality control of QHSS.
Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal/chemistry* ; Gas Chromatography-Mass Spectrometry ; Mass Spectrometry ; Quality Control

OBJECTIVES: To establish a method to identify unknown sample based on the combined use of Fourier transform infrared spectroscopy (FTIR), gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), ultra-high performance liquid chromatography-linear ion trap quadrupole-orbitrap mass spectrometry (UPLC-LTQ-Orbitrap MS) and ¹H-nuclear magnetic resonance spectroscopy (¹H-NMR) technique. METHODS: The unknown sample was directly analyzed by FTIR. The unknown sample was dissolved in methanol solution containing internal standard SKF_525A and the supernatant was detected by GC-QTOF-MS and UPLC-LTQ-Orbitrap MS. The unknown sample was dissolved in methanol-d4 solution for structural analysis of ¹H-NMR. RESULTS: The characteristic absorption peaks of FTIR spectra obtained from unknown sample were 1 682 (C=O bond), 1 503, 1 488, 1 436, 1 363, 1 256, 1 092, 1 035, 935, 840 and 800 cm^-1, the characteristic fragment ions (m/z) of GC-QTOF-MS were 86.096 4 (base peak), 58.065 1, 149.023 5, 121.028 6 and 65.038 6, the accurate mass [M+H]⁺ detected by UPLC-LTQ-Orbitrap MS was 236.127 7. The sample was identified as synthetic cathinone new psychoactive substance Eutylone by ¹H-NMR. CONCLUSIONS The method established in this study can be used for structural confirmation of Eutylone.
Methanol ; Chromatography, High Pressure Liquid/methods* ; Mass Spectrometry ; Gas Chromatography-Mass Spectrometry/methods* ; Magnetic Resonance Spectroscopy