Identification of cancer inhibitors from Hystrix brachyura bezoar extracts using LC - MS multivariate data analysis and in silico evaluation on Bcl - 2, cyclin B/CDK1, VEGF and NM23 - H1 / Identificación de inhibidores de cáncer a partir de extractos de bezoar de Hystrix branchyura usando análisis multivariado LC - MS y evaluación in silico en Bcl - 2, cyclin B/CDK1, VEGF, y NM23 - H1

Hystrix brach yura bezoar is calcified undigested material found in the gastrointestinal tract known for various medicinal benefits including as an anticancer agent. However, the H. brachyura population has been declining due to its demand and is under Malaysian law pro tection. Therefore, present study aimed to identify bezoar anticancer active compounds through metabolomics and in - silico approaches. Five replicates of bezoar powder were subjected to extraction using different solvent ratios of methanol - water (100, 75, 5 0, 25, 0% v/v). Cytotoxicity and metabolite profiling using liquid chromatography - mass spectrometry were conducted. Putative compounds identified were subjected to in - silico analysis with targeted anticancer proteins namely, Bcl - 2, Cyclin B/CDK1 complex, V EGF and NM23 - H1. The correlation of LC - MS and cytotoxicity profile pinpointed two compounds, mangiferin and propafenone. In - silico study showed both compounds exerted good binding scores to all proteins with hydrophobic interaction dominating the ligand - pr otein complex binding, suggesting the ligands act as hydrophobes in the interactions.

El bezpar de Hystrix branchyura es material calcificado sin digerir encontr ados en el tracto gastrointestinal, conocido por sus variados beneficios médicos, incluyendo propiedades anticancerosas. De todas formas, la población de H. Branchyura ha ido declinando debido a su demanda y está bajo la protección de la ley de Malasia. Po r esto, este estudio busca identificar los componentes activos anticancerosos del bezoar mediante abordajes metabolómico e in silico. Cinco réplicas de polvo de bezoar fueron sometidos a extracción usando solventes con diferentes proporciones metanol - agua (100, 75, 50, 25, 0% v/v). Se hicieron perfiles de citotoxicidad y de metabolitos usando cromatografía líquida - espectrometría de masa ( LC - MS ). Se identificaron compuestos putativos yse sometieron a a nálisis in silico, buscando las proteínas anticancerosas B cl - 2, complejo Cyclin B/CDK1, VEGF, y NM23 - H1. La correlación LC - MS y el perfil de citotoxicidad identificaron dos compuestos: mangiferina y propafenona. El estudio in silico mostró que ambos compuestos tenían buenos índices de enlace con todas las proteín as con interacción hidrofóbica dominando el enlace complejo proteína - ligando, sugeriendo que los ligandos actúan como hidrófobos en las interacciones

Establishment and verification of a real-time quantitative PCR method for determination of exogenous antibody gene copy number in CHO cells / 中国生物制品学杂志

@#Objective To establish a real-time quantitative PCR method using SYBR GreenⅠto detect the copy numbers of light chain(LC)and heavy chain(HC)of exogenous antibody gene in CHO cells,and verify and preliminarily apply this method.Methods With the B2m(β2-microglobulin)expressed stably in CHO cells as the internal reference gene,suitable primers of LC,HC genes and internal reference gene were designed respectively,and the reaction system and program of the real-time quantitative PCR method were determined. The established method was verified for the specificity,linearity,precision and durability,and used to detect the copy numbers of LC and HC genes in the recombinant cell lines of working cell bank(WCB)and cells of different passages.Results The primers of exogenous genes and internal reference gene showed specific binding to the target fragments;The efficiency of primer amplification for the B2m gene,LC gene,and HC gene was 106. 7%,106. 3% and 99. 1%,respectively,and the correlation coefficients of the linear equations were all greater than 0. 99 with a good linear relationship;The relative standard deviations(RSDs)of precision verification were all less than 1%;Few cycles of freeze-thaw in a short period had little effect on the detection results. The copy numbers of LC and HC genes in different generations of recombinant cell lines detected by the established method showed no obvious changes.Conclusion A real-time quantitative PCR method for the determination of the copy number of exogenous genes in CHO cells was successfully established with good specificity,linearity,precision and durability,which provides a reference for detecting the copy number of exogenous genes expressed in other CHO cell lines

Structural identification of the related substances in phloroglucinol injection by two-dimensional liquid chromatography-quadrupole time-of-flight mass spectrometry / 药学学报

This study aimed to identify the related substances of phloroglucinol injection by two-dimensional liquid chromatography quadrupole time-of-flight mass spectrometry (2D-LC-Q-TOF/MS). The first-dimensional separation was carried out on an HSS T3 (250 mm × 4.6 mm, 5 μm) column by gradient elution using 1.36 g·L-1 potassium dihydrogen phosphate buffer solution (pH adjusted to 3.0 with diluted phosphoric acid) and acetonitrile as the mobile phases. The separated components were then trapped in switch valve tube lines respectively and delivered to the second-dimensional desalting gradient elution which was performed with a BDS C18 (100 mm × 4.6 mm, 2.4 μm) column using 0.1% formic acid and methanol as the mobile phases. After rapid desalting, electrospray-ionization quadrupole time-of-flight high resolution mass spectrometry was used for determining the accurate masses and elemental compositions of the parents and their product ions for both phloroglucinol and its related substance. Structures of the related substances were then figured out by mass spectrometry elucidation, organic reaction mechanism analysis, and/or comparison with reference substances. Under the established analytical conditions, phloroglucinol and its related substances were adequately separated, 17 main related substances were detected and identified in the injection and its stressed samples for the first time. The identification results can provide reference for the quality control of phloroglucinol injection.

Development and validation of a method for quantitation of cefepime/avibactam in M-H broth: application to antibacterial activity using in vitro PK/PD Model / 中国临床药理学与治疗学

AIM: To establish a method for quantitation of cefepime and avibactam in M-H broth, and applicated in the in vitro dynamic PK/PD model. METHODS: The cefepime was also determined using the high-performance liquid chromatography method (HPLC), the avibactam was also determined using the liquid chromatography-mass spectrometry (LC-MS/MS), an in vitro dynamic PK/PD model was established to study the PK/PD relationship of cefepime/avibactam against carbapenem resistant Klebsiella pneumoniae (CRKP). RESULTS: The linear ranges of cefepime and avibactam were good at (0.5-20) and (0.1-25) μg/mL (r=0.999), and the lower limit concentrations were 0.5 and 0.1 μg/mL. The extraction recoveries of cefepime and avibactam in M-H broth were 88.0%-101.7% and 90.9%-95.2%, the relative standard deviation of intra-day precision and inter-day precision were less than 5.2%. The concentration-time curves were well simulated by the PK/PD model. All observed concentrations in each experiment were in the range of 20% of the targeted values. For the CRKP of MIC=8 μg/mL and MIC=16 μg/mL, the colony decreased to 2.783Log10 CFU/mL and 1.325Log10 CFU/mL at the cefepime/avibactam 2.5 g q8 h administration after 24 h. CONCLUSION: The determination method of cefepime and avibactam in broth established in this study has high sensitivity and good stability. For the CRKP with MIC≤8 μg/mL,cefepime/avibactam showed that good anti-CRKP activity under routine administration in vitro dynamic PK/PD model.

Analysis of effective components of Agaricus blazei Murill extract by LC-MS and network pharmacology analysis in treatment of chronic myeloid leukemia / 中国药理学通报

Aim To explore the potential targets and related signaling pathways of Agaricus blazei Murill (AbM ) extract in the treatment of chronic myeloid leukemia (CML) based on liquid chromatography mass spectrometry ( LC-MS ), network pharmacology, molecular docking, and were further verified by experiments in vitro. Methods The active components of AbM extract were retrieved from LC-MS, Swiss Target Prediction database was used to predict related targets, and CML disease target genes were obtained from Gen- eCards and DisGeNET databases. After screening the common targets of drug and CML, the protein-protein interaction network of the common targets was performed by STRING, and GO and KEGG enrichment a- nalysis were done by DAVID database. Cytoscape software was used to construct the network of target protein. Molecular docking was carried out by DockThor, and the Pymol software was used to make a visual picture. The inhibitory effect of AbM extract on leukemia cells K562 was determined by CCK-8 experiment, and the effect of AbM extract on the expression and phosphorylation level of related proteins was verified by Western blot. Results The prediction results showed that 126 active components of AbM extract, and 172 common targets were collected. KEGG pathway analysis results showed that PI3K/Akt/mTOR signaling pathway might play an important role in the treatment of CML disease. The IC

Design, synthesis and degradation activity of BRD4-targeting ATTECs / 药学实践杂志

Objective To design and synthesize autophagic degraders targeting BRD4 based on autophagosome tethering compound (ATTEC) strategy and test their BRD4 degradation activity. Methods BRD4-targeting ATTECs were constructed by conjugating ispinesib that used as a LC3 ligand and JQ1 through a variety of alkane linkers. The final compounds were confirmed by 1H NMR, 13C NMR and ESI-MS, and their degradation activity in different cell lines were tested by Western Blot. Results Five BRD4-ATTEC molecules were successfully synthesized for the first time. Compound 4 showed moderate BRD4 degradation activity in different cell lines. Conclusion The novel BRD4 autophagic degraders were discovered, which expanded the applicability of targeted autophagic degradation via ATTEC.

Pharmacokinetic study of HMS-01 in mice / 药学实践杂志

Objective To study the pharmacokinetics of HMS-01 in mice and provide support for subsequent studies. Methods Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to establish a sensitive and specific method for the determination of the concentration of HMS-01 in plasma and other biological samples. The pharmacokinetics of HMS-01 in C57BL/6J mice were studied by the established method. To obtain the basic pharmacokinetic parameters, three doses of HMS-01 were given orally and one dose of HMS-01 was given intravenously. Results The pharmacokinetic results of mice showed that the intestinal absorption of HMS-01 was fast, the oral bioavailability of HMS-01 in mice was moderate (50% to 70%). The exposure levels (AUC and cmax) of HMS-01 in mice increased with the increase of dosage, while the AUC was linearly correlated with the increase of dosage. After intravenous administration of HMS-01, the half-life period in mice was about 1 h which was not long. The plasma clearance rate (CLtotal.p) was 2.8 L/h·kg, which was similar to the hepatic blood flow of mice. The apparent volume of distribution (VSS) was 5 L/kg, which was much larger than the total mouse fluid. There were significant differences in AUC and F (P<0.05), but no significant differences in parameters such as cmax,AUC0−∞,t1/2,CLtot,p,MRT,Vss in male and female mice which were given 30 and 60mg/kg HWS-01 orally. Conclusion The pharmacokinetic process of HMS-01 in mice showed gender differences, and the area under the curve of blood concentration time and bioavailability of female mice were higher than that of male mice. As oral bioavailability was reasonable, further in vivo studies on HMS-01 in mice with heart failure by oral administration could be considered to provide evidence.

Structure identification and content analysis of active components in Xiaoyao pills / 药学学报

Xiaoyao pills are a famous traditional Chinese medicine collected in Welfare Pharmacy, which is a classic prescription for treating liver depression and spleen deficiency. However, its composition is complex. In order to better control the quality of Xiaoyao pills, in this study, HPLC-ion-trap time-of-flight mass spectrometry (LC-IT-TOF/MS) was used to identify the main ingredients of Xiaoyao pills, paeoniflorin, albiflorin, glycyrrhizic acid, saikosaponin A and saikosaponin B2. Then a liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed for simultaneous determination and quantification of the main compounds. Fragmentation pathways of five active components were obtained. The method was validated. Five active ingredients in Xiaoyao pills had a good linear relationship, and the values of RSD (%) of repeatability were all less than 5%, the recovery ranges were between 90% and 115%, and the values of RSD (%) of each substance were less than 10% after the sample solution is placed for 24 hours. Three batches of Xiaoyao pills (concentrated pellets) and two batches of Xiaoyao pills (water pellets) were determined, the contents of paeoniflorin in concentrated pills were more than 4.0 mg·g-1, and those in water pills were more than 2.5 mg·g-1, which was accordance with Chinese Pharmacopoeia. However, other compounds behave differently. This method has high sensitivity and reliable measurement results, which provides basis for quality control of Xiaoyao pills and material basis for pharmacology research.

Proteomic Difference Analysis of Whole Blood and Bloodstains / 法医学杂志

OBJECTIVES@#To study the changes of protein levels in peripheral blood after it dried.@*METHODS@#The proteins from whole blood and bloodstains were detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and normalized by the label-free quantification (LFQ) method. The differential proteins were analyzed by using R 4.2.1 software, limma and edgeR package. The analysis of biological function, signaling pathway and subcellular localization for the differential proteins was then performed.@*RESULTS@#A total of 623 and 596 proteins were detected in whole blood and bloodstains, respectively, of which 31 were statistically significant in the quantitative results, including 10 up-regulated and 21 down-regulated proteins in bloodstains.@*CONCLUSIONS@#The protein abundances in whole blood and bloodstains are highly correlated, and the variation of protein abundances may be related to the changes of endogenous and structural proteins in cells. The application of proteomics technology can assist the screening and identification of protein biomarkers, thereby introducing new biomarkers for forensic research.

Metabonomics Analysis of Brain Stem Tissue in Rats with Primary Brain Stem Injury Caused Death / 法医学杂志

OBJECTIVES@#To explore the potential biomarkers for the diagnosis of primary brain stem injury (PBSI) by using metabonomics method to observe the changes of metabolites in rats with PBSI caused death.@*METHODS@#PBSI, non-brain stem brain injury and decapitation rat models were established, and metabolic maps of brain stem were obtained by LC-MS metabonomics method and annotated to the HMDB database. Partial least square-discriminant analysis (PLS-DA) and random forest methods were used to screen potential biomarkers associated with PBSI diagnosis.@*RESULTS@#Eighty-six potential metabolic markers associated with PBSI were screened by PLS-DA. They were modeled and predicted by random forest algorithm with an accuracy rate of 83.3%. The 818 metabolic markers annotated to HMDB database were used for random forest modeling and prediction, and the accuracy rate was 88.9%. According to the importance in the identification of cause of death, the most important metabolic markers that were significantly up-regulated in PBSI group were HMDB0038126 (genipinic acid, GA), HMDB0013272 (N-lauroylglycine), HMDB0005199 [(R)-salsolinol] and HMDB0013645 (N,N-dimethylsphingosine).@*CONCLUSIONS@#GA, N-lauroylglycine, (R)-salsolinol and N,N-dimethylsphingosine are expected to be important metabolite indicators in the diagnosis of PBSI caused death, thus providing clues for forensic medicine practice.

Metabolomics of nasal lavage fluid in patients with allergic rhinitis treated by Xiaoqinglong Decoction / 中国中药杂志

This study used nasal lavage fluid for metabolomics to explore its feasibility, and applied it to the clinical metabolomics study of Xiaoqinglong Decoction in the treatment of allergic rhinitis(AR), aiming to investigate the molecular mechanism of Xiaoqing-long Decoction in the treatment of AR through differential changes in local nasal metabolism. AR patients were selected as the research subjects, and nasal lavage fluid was collected as the sample. Metabolomics analysis using liquid chromatography-mass spectrometry was performed on normal group, AR group, and Xiaoqinglong Decoction group. The differences in metabolic profiles among the groups were compared using principal component analysis and partial least squares discriminant analysis, and differential metabolites were identified and subjected to corresponding metabolic pathway analysis. The results showed that Xiaoqinglong Decoction significantly improved the symptoms of AR patients. The metabolomics analysis revealed 20 differential metabolites between AR group and Xiaoqinglong Decoction group. The core metabolite with a trending return in comparison to normal group was trimethyladipic acid. The metabolites were involved in multiple pathways, including β-alanine metabolism, glutathione metabolism, and phenylalanine, tyrosine, and tryptophan biosynthesis. The feasibility of applying nasal lavage fluid in nasal metabolomics was preliminarily demonstrated. Differential metabolites and enriched pathways in the treatment of AR patients with Xiaoqinglong Decoction were identified, indicating that it may improve rhinitis symptoms through the regulation of various metabolites, including antioxidant effects and correction of Th1/Th2 imbalance.

LC-MS fingerprint and multi-indicator components analysis of classical formula Gualou Xiebai Banxia Decoction / 中国中药杂志

This study developed an optimal pre-processing technique for the reference substance of the classic formula Gualou Xiebai Banxia Decoction(GXBD) and established a comprehensive quality control method for GXBD reference substance to provide a reference for its overall quality evaluation. The authors prepared 15 batches of GXBD samples and innovatively used the extracted ion chromatogram under the base peak chromatogram mode to establish a liquid chromatography-mass spectrometry(LC-MS) fingerprint, identify characteristic peaks, and perform quantitative analysis of indicator components. The yield of the 15 batches of GXBD samples ranged from 50.28% to 76.20%. In the positive ion mode, 12 common characteristic peaks were detected in the LC-MS fingerprint, and the structures of five common peaks were identified by comparison with reference standards. The similarity between the fingerprint profiles of different batches of samples and the reference fingerprint profile ranged from 0.920 to 0.984. Finally, liquid chromatography-triple quadrupole mass spectrometry(LC-QQQ/MS) in multiple reaction monitoring(MRM) mode was used to determine the content of eight indicator components in GXBD, including loliolide, chrysoeriol, rutin, cucurbitacin D, macrostemonoside Ⅰ, 25S-timosaponin B Ⅱ, 25R-timosaponin B Ⅱ, and peptide proline-tryptophan-valine-proline-glycine(PWVPG). The method established in this study can reduce matrix interference in the compound, and it has good accuracy, stability, and practical value. It effectively reflects the quality attributes of GXBD samples and can be used for the comprehensive quality control of GXBD.

Pharmacokinetic study about compatibility of Eucommia ulmoides and Psoralea corylifolia / 中草药·英文版

OBJECTIVE@#The compatibility of Eucommia ulmoides (Eu) and Psoralea corylifolia (Pc) on the pharmacokinetic (PK) properties in the rat was explored in this study.@*METHODS@#Eu extract, Pc extract and the combined extracts (crude drug ratio was 2:1) was administered by gavage, respectively. Two PK experiments were conducted. In first one, the blood samples were collected via the occuli chorioideae vein to get the PK properties of the components. In second one, the blood samples were simultaneously collected via the internal jugular vein or portal vein at different time points and the concentrations of target ingredients were detected by LC/MS/MS to clear the location where the interaction of Eu and Pc took place in vivo.@*RESULTS@#Eight of 11 ingredients in Eu and Pc extract were determined in rat plasma. The exposure levels of geniposidic acid (GPA), aucubin (AU), geniposide (GP), pinoresinol diglucoside (PDG), psoralen glycosides (PLG) and isopsoralen glycosides (IPLG) were decreased 1/5-2/3 after administration of combined extracts. Comparing to the combined administration, the exposure of GPA and AU in plasma of single Eu administration collected via the portal vein were decreased 1/3-2/3, and the values of AUC0-24h and AUC0-∞ of GP collected from the portal vein or internal jugular vein were double increased. The other components' parameters were not significantly changed.@*CONCLUSION@#In summary, the Pc and Eu combined administration could affect the exposure of the main components of Eu extract in rats due to the changed intestinal absorption. The research on the compatibility of Pc and Eu was helpful to guide the clinical administration of Eu and Pc simultaneously.

Research progress in role of autophagy in diabetic wound healing and traditional Chinese medicine intervention / 中国中药杂志

Diabetic ulcer(DU) is a chronic and refractory ulcer which often occurs in the foot or lower limbs. It is a diabetic complication with high morbidity and mortality. The pathogenesis of DU is complex, and the therapies(such as debridement, flap transplantation, and application of antibiotics) are also complex and have long cycles. DU patients suffer from great economic and psychological pressure while enduring pain. Therefore, it is particularly important to promote rapid wound healing, reduce disability and mortality, protect limb function, and improve the quality of life of DU patients. By reviewing the relevant literatures, we have found that autophagy can remove DU wound pathogens, reduce wound inflammation, and accelerate ulcer wound healing and tissue repair. The main autophagy-related factors microtubule-binding light chain protein 3(LC3), autophagy-specific gene Beclin-1, and ubiquitin-binding protein p62 mediate autophagy. The traditional Chinese medicine(TCM) treatment of DU mitigates clinical symptoms, accelerates ulcer wound healing, reduces ulcer recurrence, and delays further deterioration of DU. Furthermore, under the guidance of syndrome differentiation and treatment and the overall concept, TCM treatment harmonizes yin and yang, ameliorates TCM syndrome, and treats underlying diseases, thereby curing DU from the root. Therefore, this article reviews the role of autophagy and major related factors LC3, Beclin-1, and p62 in the healing of DU wounds and the intervention of TCM, aiming to provide reference for the clinical treatment of DU wounds and subsequent in-depth studies.

LC-MS analysis of 2-(2-phenylethyl) chromones in sodium chloride-treated suspension cells of Aquilaria sinensis / 中国中药杂志

Qualitative and quantitative analysis of 2-(2-phenylethyl) chromones in sodium chloride(NaCl)-treated suspension cells of Aquilaria sinensis was conducted by UPLC-Q-Exactive-MS and UPLC-QQQ-MS/MS. Both analyses were performed on a Waters T3 column(2.1 mm×50 mm, 1.8 μm) with 0.1% formic acid aqueous solution(A)-acetonitrile(B) as mobile phases at gradient elution. MS data were collected by electrospray ionization in positive ion mode. Forty-seven phenylethylchromones was identified from NaCl-treated suspension cell samples of A. sinensis using UPLC-Q-Exactive-MS, including 22 flindersia-type 2-(2-phenylethyl) chromones and their glycosides, 10 5,6,7,8-tetrahydro-2-(2-phenylethyl) chromones and 15 mono-epoxy or diepoxy-5,6,7,8-tetrahydro-2-(2-phenylethyl) chromones. Additionally, 25 phenylethylchromones were quantitated by UPLC-QQQ-MS/MS. Overall, the rapid and efficient qualitative and quantitative analysis of phenylethylchromones in NaCl-treated suspension cells of A. sinensis by two LC-MS techniques, provides an important reference for the yield of phenylethylchromones in Aquilariae Lignum Resinatum using in vitro culture and other biotechnologies.

Pharmacokinetic study of five ingredients from Chitong xiaoyanling granules in rats / 中国药房

OBJECTIVE To study the pharmacokinetics of paeoniflorin， hesperidin， naringenin， formononetin and enoxolone from Chitong xiaoyanling granules in rats. METHODS Six male SD rats fasted but not deprived of water for 12 h were given Chitong xiaoyanling granules （5.0 g/kg） intragastrically at one time. Blood was collected from inner canthus of rats at different time points after administration. Plasma samples were pretreated with acetonitrile precipitated protein （sulfamethoxazole as internal standard）， and the concentrations of 5 ingredients in plasma were determined by liquid chromatography-tandem mass spectrometry （LC-MS/MS）. The pharmacokinetic parameters of each ingredient were calculated using DAS 3.0 software. RESULTS After intragastric administration of Chitong xiaoyanling granules， tmax and t1/2 of formononetin were the shortest among 5 ingredients （0.25 h and 0.39 h， respectively）. For naringenin and enoxolone， the tmax was shorter， but t1/2 was longer， and there was an obvious double-peak phenomenon in the drug-time curve of naringenin. Compared with the other three components， cmax and AUC of paeoniflorin and hesperidin were not directly proportional to the content of in vitro components. CONCLUSIONS Formononetin， naringin and enoxolone in Chitong xiaoyanling granules were absorbed rapidly in rats， while paeoniflorin and hesperidin were absorbed slowly.

Analysis of Forty-Two Psychoactive Substances in a Single Hair by Micro-Segmental Technique / 法医学杂志

OBJECTIVES@#To establish an LC-MS/MS method based on single hair micro-segmental technique, and verify the detection of 42 psychoactive substances in 0.4 mm hair segments.@*METHODS@#Each piece of single hair was cut into 0.4 mm segments and extracted by sonication and the segments were immersed in dithiothreitol-containing extraction medium. Mobile phase A was the aqueous solution containing 20 mmol/L ammonium acetate, 0.1% formic acid, and 5% acetonitrile. Mobile phase B was acetonitrile. An electrospray ionization source in positive ion mode was used for data acquisition in multiple reaction monitoring (MRM) mode.@*RESULTS@#The 42 psychoactive substances in hair had a good linear relationship within their respective linear ranges (r>0.99), the limits of detection were 0.2-10 pg/mm, the limits of quantification were 0.5-20 pg/mm, the intra-day and inter-day precisions were 1.5%-12.7%, the intra-day and inter-day accuracies were 86.5%-109.2%, the recovery rates were 68.1%-98.2%, and the matrix effects were 71.3%-111.7%. The method was applied to hair samples collected from one volunteer at 28 d after a single dose of zolpidem, with zolpidem detected in 5 hairs was 1.08-1.60 cm near the root tip, and the concentration range was 0.62-20.5 pg/mm.@*CONCLUSIONS@#The micro-segmental technique of single hair analysis can be applied to the investigation of drug-facilitated sexual assault cases.

Detection of Carbamazepine and Its Metabolites in Blood Samples by LC-MS/MS / 法医学杂志

OBJECTIVES@#To establish a method for the detection of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS).@*METHODS@#The blood samples were treated with 1-butyl-3-methylimidazolium hexafluorophosphate as an extraction solvent. The samples were extracted by ultrasound-assisted extraction and separated by ZORBAX Eclipse Plus C18, 95Å column. The mobile phase A aqueous solution containing 0.1% formic acid and 10 mmol/L ammonium acetate, and mobile phase B mixed organic solvent containing acetonitrile/methanol (Vacetonitrile∶Vmethanol=2∶3) were used for gradient elution at the flow rate of 1.00 mL/min. An electrospray ion source in positive mode was used for detection in the multiple reaction monitoring.@*RESULTS@#The linearities of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples were good within the corresponding range, with correlation coefficients (r) greater than 0.995 6. The limits of detection were 3.00, 0.40 and 1.30 ng/mL, respectively. The limit of quantitation were 8.00, 1.00 and 5.00 ng/mL, respectively. The extraction recoveries ranged from 76.00% to 106.44%. The relative standard deviations of the intra-day and inter-day precisions were less than 16%. Carbamazepine and its main metabolite 10,11-dihydro-10,11-epoxycarbamazepine were detected in blood samples of death cases with a mass concentration of 2.71 μg/mL and 252.14 ng/mL, respectively.@*CONCLUSIONS@#This method has high sensitivity and good selectivity, which is suitable for the detection of carbamazepine and its metabolites in blood samples, and can be used for carbamazepine-related forensic identifications.

Determination of 22 phospholipids in serum by ultra performance liquid chromatography-tandem mass spectrometry / 中华劳动卫生职业病杂志

Objective: To establish ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the determination of 22 phospholipids in serum. Methods: In September 2022, Using synthetic non endogenous phospholipids as internal standard, phospholipids in serum were extracted by methanol-dichloromethane (2∶1, V/V) protein precipitation method. Chromatographic separation was achieved on an ACQUITY UPLC BEH shield RP18 column, and the mobile phase was methanol/water (5∶95, V/V) containing 10 mM ammonium formate and methanol. Detection was performed in multiple reaction monitoring mode with ion mode switching. And the method was applied by analyzing phospholipids in the serum of coal workers' pneumoconiosis patients. Results: The 22 phospholipids showed good linear relationships in their respective concentration ranges and the correlation coefficients were higher than 0.990. The spiked recoveries of the 22 phospholipids were 81.03%-121.63% at the three spiked levels. The intra-assay were less than 14.52%, and the inter-assay were less than 15.00%. Conclusion: The method with the advantages of simplicity, stability and high sensitivity, and it can be used for the analysis of phospholipids in serum.

Rapid determination of acetaminophen in plasma by LC-MS/MS / 中华劳动卫生职业病杂志

Objective: To establish a method for the rapid determination of acetaminophen (APAP) in human plasma by LC-MS/MS. Methods: The plasma samples were extracted by methanol and acetonitrile (1: 1) and purified directly. C(18) column was used for sample separation. The mobile phase were methanol (5 mmol/L ammonium acetate) and water (5 mmol/L ammonium acetate). Samples were analyzed by LC MS/MS with the electrospray ionization multi reaction monitoring (MRM) mode. Results: The calibration curves of APAP was linear in the concentration range of 0~10 mg/L, the correlation coefficient (r) was greater than 0.999 0. The relative standard deviation within and between batches was less than 10%. The recovery rate were 96.81%~101.7%. The detection limit of the method was 0.1 μg/L and the lower limit of quantification was 0.3 μg/L. Conclusion: This method has strong specificity, high sensitivity and reliable determination results. It is suitable for the rapid analysis of clinical plasma samples.