LC-MS/MS AND GC-MS PROFILING AND THE ANTIOXIDANT ACTIVITY OF CARISSA CARANDAS LINN. FRUIT EXTRACTS

Objective: The present study was carried out with three varieties (green, pink, and sweet) of Carissa carandas fruit extract for the identification of phytochemical constituents in C. carandas fruit extracts using Liquid Chromatography-Mass Spectrometry (LC-MS/MS) and Gas Chromatography-Mass Spectrometry (GCMS)Methods: LC MS/MS and GCMS analysis were adopted to study three varieties of C. carandas fruit, namely green, pink, and sweet, using different solvent extractions such as ethanol, methanol, and aqueous.Results: High levels of phenolic acids and flavonoids in the green variety were beneficial for anti-diabetic activity due to their antioxidant properties. Among the three varieties of tested samples, the maximum concentration was observed in the ethanol extract of the green varieties (2.485 mg/g FW) compared to the ethanol extract of the pink (1.564 mg/g FW) and sweet (1.285 mg/g) varieties, respectively. Ethanol extract of the green variety has a high level of anthocyanin, which increases tolerance to disease. The separation and identification of fatty acids in C. carandas fruit were determined through analysis. The sweet C. carandas variety recorded the highest concentration of fatty acids (147.2 mg/100g FW) compared to the pink and green varieties (94.9 mg/100 g FW) and (72.79 mg/100 g FW), respectively, and could successfully identify the number of phytonutrients that have health benefits. Further work is being carried out, which may lead to the development of herbal medicine.Conclusion: The present study concludes that phytochemicals present in C. carandas fruit, extracted by LC-MS and GC MS analysis, contain antioxidant and anti-diabetic effects.

An LC-MS/MS Method Development and Validation for the Quantification of Infigratinib in K2EDTA Human Plasma

A validated liquid chromatography with tandem mass spectrometry (LC-MS-MS) technology was developed for the quantification of infigratinib, using a simple and specific approach. This method utilizes a liquid-liquid extraction (LLE) strategy to achieve high sensitivity. The analytical approach that was developed underwent validation in terms of many characteristics including specificity, sensitivity, carry-over, recovery, precision, matrix effect, accuracy, and stability. The elution of the drug and IS occurred in a time frame of 6.5 minutes using a PhenomenexSB-C18 column (250 × 4.6 mm x 5 ?m). The mobile phase consisted of a mixture of acetonitrile and 0.1% v/v formic acid in water, with a ratio of 80:20. The infusion flow rate was set at 0.9 mL/min. The retention times (RT) of infigratinib and IS were determined to be 5.12 and 3.31 minutes, respectively. The elution time required for complete separation of infigratinib was 6.5 minutes. The equation of the linear regression line was determined to be y = 0.994x + 2.662, and the coefficient of determination (r2) was calculated to be 0.999. The coefficient of variation (%CV) obtained for the calibration graph of infigratinib was determined to be less than or equal to 3.73. The matrix effect was assessed by calculating the coefficient of variation (%CV) for the High and low quality control (QC) samples, yielding values of 1.64 and 0.70% respectively.

Simultaneous determination of bepotastine and hydroxychloroquine concentrations in human breast milk by LC-MS/MS / 中国药房

OBJECTIVE To establish a liquid chromatography-tandem mass spectrometry （LC-MS/MS） method for the simultaneous determination of bepotastine and hydroxychloroquine concentrations in human breast milk and apply it in clinical practice. METHODS The milk samples （50 μL） were precipitated with 200 μL methanol containing the internal standard （100 ng/mL chloroquine）， and the supernatant was taken for analysis after vortexing and centrifugation. The separation was performed on a Waters ACQUITY UPLC HSS T3 column with mobile phase consisted of 0.1% formic acid-10 mmol/L ammonium acetate solution （phase A） and methanol （phase B） at gradient elution of 0.35 mL/min. The injection volume was 2 μL， and the analysis time was 4 min. The detection of the analytes was performed by electrospray ionization in positive mode by multiple reaction monitoring with the transition of m/z 388.9→201.9 （bepotastine）， m/z 336.3→247.1 （hydroxychloroquine）， and m/z 320.2→247.2 （chloroquine）. The established LC-MS/MS method was researched in methodology and used to determine the drug concentrations in the breast milk of 1 case of lactating patient. RESULTS The linear range of bepotastine was 2-200 ng/mL（ r＝0.999）， and hydroxychloroquine was 50-1 000 ng/mL （r＝0.998）. The intra-assay and inter-assay precisions were both ≤15%， and the accuracy， extraction recovery， matrix effect， and stability all met the acceptance criteria for bioanalytical method validation. The concentration result of bepotastine and hydroxychloroquine in the breast milk of the lactating patient showed， after 2 h and 14 h， the concentrations of bepotastine in the breast milk of the patient were 34.95 ng/mL and 5.72 ng/mL； those of hydroxychloroquine were 211.92 ng/mL and 104.18 ng/mL， respectively. The relative infant doses were 1.83% and 0.56%， respectively. CONCLUSIONS The established method is simple， rapid， and sensitive. It is suitable for simultaneous determination of bepotastine and hydroxychloroquine concentrations in human milk and can provide reference for safe drug use during lactation.

Simultaneous determination of bepotastine and hydroxychloroquine concentrations in human breast milk by LC-MS/MS / 中国药房

OBJECTIVE To establish a liquid chromatography-tandem mass spectrometry （LC-MS/MS） method for the simultaneous determination of bepotastine and hydroxychloroquine concentrations in human breast milk and apply it in clinical practice. METHODS The milk samples （50 μL） were precipitated with 200 μL methanol containing the internal standard （100 ng/mL chloroquine）， and the supernatant was taken for analysis after vortexing and centrifugation. The separation was performed on a Waters ACQUITY UPLC HSS T3 column with mobile phase consisted of 0.1% formic acid-10 mmol/L ammonium acetate solution （phase A） and methanol （phase B） at gradient elution of 0.35 mL/min. The injection volume was 2 μL， and the analysis time was 4 min. The detection of the analytes was performed by electrospray ionization in positive mode by multiple reaction monitoring with the transition of m/z 388.9→201.9 （bepotastine）， m/z 336.3→247.1 （hydroxychloroquine）， and m/z 320.2→247.2 （chloroquine）. The established LC-MS/MS method was researched in methodology and used to determine the drug concentrations in the breast milk of 1 case of lactating patient. RESULTS The linear range of bepotastine was 2-200 ng/mL（ r＝0.999）， and hydroxychloroquine was 50-1 000 ng/mL （r＝0.998）. The intra-assay and inter-assay precisions were both ≤15%， and the accuracy， extraction recovery， matrix effect， and stability all met the acceptance criteria for bioanalytical method validation. The concentration result of bepotastine and hydroxychloroquine in the breast milk of the lactating patient showed， after 2 h and 14 h， the concentrations of bepotastine in the breast milk of the patient were 34.95 ng/mL and 5.72 ng/mL； those of hydroxychloroquine were 211.92 ng/mL and 104.18 ng/mL， respectively. The relative infant doses were 1.83% and 0.56%， respectively. CONCLUSIONS The established method is simple， rapid， and sensitive. It is suitable for simultaneous determination of bepotastine and hydroxychloroquine concentrations in human milk and can provide reference for safe drug use during lactation.

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.

Determination of hydrogen sulfide in Blood by LC-MS/MS / 中国法医学杂志

Objective To establish a method for determining hydrogen sulfide(H2S)in blood and apply it to practical cases.Methods A delute solution was achieved by adding 0.8 mL saturated borax solution into 0.2 mL blood sample was diluted with.1 mL acetonitrile solution containing 0.1％formic acid was then taken in a test tube,followed by adding 0.1 mL dilute solution and 0.1 mL thiozine aqueous solution(1％).After thorough mixing,the mixture was left to stand for 30 minutes.Subsequently,the sample was subjected to liquid chromatography-tandem mass spectrometry(LC-MS/MS)analysis after centrifugation and membrane filtration.Results The results showed that H2S exhibited good linearity within the concentration range of 10～2 000 ng/mL,with the R2 value of 0.998 5.The detection limit was 5 ng/mL,and the quantification limit was 10 ng/mL.In three cases of H2S poisoning,sulfur ions were detected in the blood of the deceased individuals,with concentrations ranging from 0.17 to 0.56 μg/mL.Conclusion For the first time,this study established a LC-MS/MS method for determining H2S in blood,which can meet the detection needs of H2S poisoning cases.

Detecting Ketamine analogues in hair samples by QTRAP LC-MS/MS / 中国法医学杂志

Objective To develop a method for the determination of ketamine analogues in hair samples by liquid chromatography quadrupole linear ion trap mass spectrometry(QTRAP LC-MS/MS).Methods 20 mg of washed and dried hair was added to 1 mL extracting solution and then prepared using an ultrasonic extraction with frozen pulverization method.After centrifugation and purification with membrane,the supernatant was separated in a ACQUITY UPLC? HSS T3 column with gradient elution,finally tested with multiple reaction monitoring for the detection of 10 ketamine analogues.The above method was applied for quantitative analysis of ethylfluamine,F-norketamine and tiletamine in 20 positive samples.Results When the concentration ranged from 0.01 to 2.00 ng/mg,there was good linearity for 10 ketamine analogues with the correlation coefficients over 0.99.The recoveries ranged from 89.1％to 106.1％,and the matrix effects were between 88.3％and 106.0％.Among the 20 positive samples,the contents of ethylfluamine,F-norketamine and tiletamine in hair ranged between 0.02～8.35 ng/mg,0.01～0.94 ng/mg and 0.02～10.93 ng/mg,respectively.Their mean values were 1.59 ng/mg,0.28 ng/mg and 2.69 ng/mg.Their medians were 0.40 ng/mg,0.19 ng/mg and 2.11 ng/mg.Conclusion The established method was simple,efficient,reliable and suitable for the determination of ketamine analogues in hair.The data provided reference for the drug control and forensic science practice.

Aplicação da Toxicologia Analítica Verde no desenvolvimento de metodologias baseadas em LC-MS para detecção de Novas Substâncias Psicoativas em amostras biológicas / Application of Green Analytical Toxicology to the development of LC-MS-based methodologies for the detection of New Psychoactive Substances in biological samples

No início dos anos 2000, as Novas Substâncias Psicoativas (NPS) emergiram de forma sem precedentes causando uma drástica mudança no mercado de drogas sintéticas mundial. Estas substâncias são sintetizadas para fins ilícitos e mimetizam o efeito psicoativo das drogas tradicionais. Até o momento, mais de 1000 substâncias foram reportadas mundialmente, representando um grande problema de saúde pública principalmente associado ao desconhecimento das suas propriedades toxicológicas. Por este motivo, métodos analíticos para detectar e quantificar estas substâncias em materiais biológicos são importantes nos casos de toxicologia analítica e forense. Contudo, a tendência de reduzir o impacto ambiental destas metodologias tem ganhado popularidade com a Toxicologia Analítica Verde (GAT). Portanto, o objetivo do presente trabalho foi desenvolver novas técnicas analíticas para analisar as principais classes de NPS em amostras biológicas enquanto aplicando os princípios sustentáveis estabelecidos pela GAT. Os resultados obtidos no presente trabalho são apresentados como coletânea de artigos científicos publicados em revistas. Estes estão descritos nos capítulos 4 a 8. No capítulo 4, uma revisão sobre os desafios no desenvolvimento de técnicas de preparo de amostra para fins forenses é abordada com foco no uso das matrizes secas. No Capítulo 5, está descrito a aplicação da microextração líquido-líquido dispersiva para catinonas sintéticas em amostras de sangue total e urina. No capítulo 6, o artigo descreve o desenvolvimento da técnica microextração líquido-líquido homogênea com solventes de hidrofilicidade comutável para canabinoides sintéticos em amostras de plasma. No capítulo 7, a microextração em fase líquida em placas de 96 poços, cunhada extração paralela em membranas artificiais líquidas, foi desenvolvida para diferentes classes de drogas de abuso, incluindo NPS. O capítulo 8 mostra o desenvolvimento de uma extração por eletromembrana também no formato de placa de 96 poços para catinonas sintéticas em amostras de sangue total. Em todos os trabalhos, as técnicas de extração foram desenvolvidas, otimizadas e validadas. Os princípios da GAT foram aplicados de diferentes formas, como reduzindo o volume de amostra, simplificando os procedimentos, evitando o uso de solventes orgânicos, dentre outros. Assim, alternativas mais sustentáveis para a análise de drogas de abuso em amostras biológicas foram apresentadas e estas ajudam a consolidar e difundir o conceito do desenvolvimento de métodos analíticos com consciência ambiental além de fornecer ferramentas para auxiliar o controle das NPS no país

In the early 2000s, New Psychoactive Substances (NPS) emerged and unprecedentedly changed the illicit drug market. These substances are synthesized for illicit purposes and mimic the psychoactive effect of traditional drugs of abuse. To date, more than 1000 substances have been reported worldwide, representing a major public health problem mainly associated with their mostly unknown toxicological properties. In this context, analytical methods able to detect and quantitate these new drugs in biological specimens are important in cases of analytical and forensic toxicology. However, reducing the environmental impact of these methodologies has recently gained popularity with Green Analytical Toxicology (GAT). Therefore, the aim of this work was to develop new analytical techniques to analyze the main classes of NPS in biological samples while applying the environmentally friendly principles established by GAT. The results obtained throughout the development of the present work were split into four papers (chapters 4-8). In chapter 4, a review of common challenges faced during the development of new sample preparation techniques for forensic applications is described focusing on the use of dried matrices. In chapter 5, the application of dispersive liquid-liquid microextraction for synthetic cathinones in whole blood and urine samples is described. In chapter 6, the application of the somewhat recent switchable hydrophilicity solvent-based homogenous liquidliquid microextraction to synthetic cannabinoids in plasma samples is reported. In chapter 7, liquid-phase microextraction in the 96-well plate format, termed parallel artificial liquid membrane extraction, for different classes of drugs of abuse, including NPS, in plasma samples is presented. In chapter 8, an electromembrane extraction in the 96-well plate format for synthetic cathinones in whole blood samples was developed. In this work, sample preparation techniques were developed, optimized and validated. The principles of sustainable chemistry in method development were applied in different ways, such as reducing the sample volume, simplifying procedures, avoiding the use of organic solvents, among others. Thus, greener alternatives were presented for the analysis of drugs of abuse in biological samples and contribute to consolidate and spread this trend of environmental consciousness during method development. Additionally, valuable techniques that can be used in the combat against NPS were provided

Development and Validation of the Stability Indicating Assay Methodology employing LC-MS/MS for Concurrent Quantification of Dapagliflozin Propanediol Monohydrate and Metformin Hydrochloride: Probable Degradants Based on Mass Spectra

For the concurrent measurement of Dapagliflozin Propanediol Monohydrate (DAPA) and Metformin Hydrochloride (MET) in combined dosage form, a quick, accurate, specific and easy Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) approach was created. The method was performed on a column C8 RRHD Eclipse (150 × 4.60 mm, 5 µm). 5 mM Ammonium Acetate Buffer pH-4.0, Methanol and Acetonitrile were the components of the mobile phase in the ratios of 30:65:05, respectively. The effluent was detected at 227 nm at a flow rate of 0.4 mL/min. The observed retention times for DAPA and MET were 7.297 and 3.230 min, respectively. The drug was stressed by being exposed to acid and alkali hydrolysis. From the mass spectra, it was found that two degradant peaks were observed in the standard mixture and the sample during alkali stress condition and probable degradants formed. The developed approach was validated in accordance with ICH guidelines. With correlation coefficients of 0.9969 for DAPA and 0.9975 for MET, it was discovered that the standard curve was linear over the range of 60-140 µg/mL and 300-700 µg/mL for DAPA and MET, respectively. The limit of detection (LOD) was 2.959 µg/mL and 8.893 µg/mL for DAPA and MET, respectively. The limit of quantification (LOQ) was 8.967 µg/mL and 26.949 µg/mL for DAPA and MET, respectively. The % recovery was determined in between 98 to 102%. The precision was within the limit (Relative Standard Deviation (RSD) <2%). The proposed stability indicating LC-MS/MS method can be successfully utilized for simultaneous estimation of DAPA and MET in combined dosage form without any prior separation of individual drugs and no interference was found due to degradant formed during stress condition.

IN-SILICO TOXICITY ASSESSMENT AND TRACE LEVEL QUANTIFICATION OF VERATRYL CHLORIDE A POTENTIAL GENOTOXIC IMPURITY IN IVABRADINE HYDROCHLORIDE USING LC-MS/MS

A sensitive and selective liquid chromatography-mass spectrometry (LC-MS/MS) method using multiple reaction monitoring (MRM) mode was developed and validated for trace analysis of 4-(chloromethyl)-1, 2-dimethoxybenzene (Veratryl chloride) a potential genotoxic impurity in Ivabradine hydrochloride (IVB). Chromatographic separation was performed on a Poroshell 120EC C18 (50 × 3.0 mm, 2.7 ?m) column using a mixture of 10 mM ammonium formate and acetonitrile in isocratic elution mode at a 0.25 mL/min flow rate. A simple pre-column derivatization with di-ethylamine was employed for the derivatization of the veratryl chloride. The developed LC-MS/MS method was linear and accurate in the 1.5–10.0 ppm concentration range with r2 ? 0.999 and percent recoveries greater than 90%. The developed method was precise with RSD (%) of not more than 4.5%. In-silico genotoxicity and carcinogenicity potential of veratryl chloride was assessed using ICH M7 principles found to be positive. The developed method can identify and quantify veratryl chloride in IVB, hence can be applied by quality control labs of pharmaceutical industries for trace quantification.

Neuroprotective effect of Capparis ovata Desf. var. palaestina Zoh. on H2O2­induced neurotoxicity in SH­SY5Y cells / Efecto neuroprotector de Capparis ovata Desf. var. palaestina Zoh. sobre la neurotoxicidad inducida por H2O2 en células SH ­SY5Y

The neuroprotective effect of flower and fruit parts of Capparis ovata Desf. var. palaestina Zoh. plant was investigated in H2O2-induced cytotoxicity in SH-SY5Y cells. The cells were treated with H2O2 alone or pretreated with flower (COMFL) and fruit extract (COMFR) of C. ovatavar. palaestina. MTT, xCELLigence, and qualitative and quantitative determination of phytochemical constituents in the extracts by LC-MS/MS methods were employed. COMFL and COMFR had a neuroprotective effect and this effect was stronger when the presence of oxidative stress. The mass spectrums revealed the presence of flavonoids and phenolic acid derivatives in the extracts. According to quantitative analyses, the main compounds were myristoleic acid, apigenin, caffeic acid, caffeic acid-3-glucoside, and 5-cynapoil quinic acid in both COMFL and COMFR and rutin was found in COMFL. The extracts could inhibit H2O2induced neuronal cell death which might be beneficial for the pretreatment of oxidative stress in neurodegenerative diseases.

Se investigó el efecto neuroprotector de flores y frutos de Capparis ovata Desf. var. palaestina Zoh sobre la citotoxicidad inducida por H2O2en células SH-SY5Y. Las células se trataron con H2O2solo o se pretrataron con extracto de flores (COMFL) y frutos (COMFR) de C. ovatavar. palaestina. Se emplearon MTT, xCELLigence y determinación cualitativa y cuantitativa de constituyentes fitoquímicos en los extractos mediante LC-MS/MS. COMFL y COMFR que tuvieron un efecto neuroprotector y este efecto fue mayor cuando hubo estrés oxidativo. Los espectros de masas revelaron la presencia de flavonoides y derivados del ácido fenólico en los extractos. Según los análisis cuantitativos, los compuestos principales fueron ácido miristoleico, apigenina, ácido cafeico, ácido cafeico-3-glucósido y ácido quínico 5-cinapoil tanto en COMFL como en COMFR y se encontró rutina en COMFL. Los extractos podrían inhibir la muerte celular neuronal inducida por H2O2, lo que podría ser beneficioso para el pretratamiento del estrés oxidativo en enfermedades neurodegenerativas.

Selective Separation and Mass Spectral Characterization of Degradants in Viloxazine by LC-MS/MS

This research describes a novel technique for the selective separation of degradants from API employing HPLC and online coupling of a triple quadrupole mass analyzer and PDA detector with a SCIEX QTRAP 5500 mass spectrometer. Chromatography was used to separate all degradants on the column Agilent eclipse XDB (150 mm x 4.6 mm, 3.5 ?) with mobile phase ACN: 0.1% TEA (40:60) %v/v. The highest absorption was found to occur at 220 nm, which allows for simultaneous detection without being impacted by the placebo matrix. According to the general ICH recommendations, the suggested RP-HPLC method was accepted. All of the metrics- specificity, linearity, LoD, LoQ, accuracy, precision and robustness of validation were deemed sufficient. The proposed method exhibits strong correlation and great linearity over the range of (12.5–75 ?g/mL). The accuracy trials produced consistent recoveries (95–105%), while the precision experiments' percent RSD was less than 2%. The intrinsic stability of the drug molecules in the current formulation could be ascertained by conducting forced degradation studies to assess the degradation products produced under various stress settings. The degradants produced were well separated and further characterized by MS/MS studies. The newly devised approach was demonstrated to be stable and sensitive to all degradants during validation tests. Validation trials demonstrate that the newly developed method was also accurate, precise, resilient, selective, and linear within the necessary operating range.

ANALYTICAL METHOD VALIDATION AND BIOEQUIVALENCE STUDY OF ERLOTINIB 150 MG TABLETS IN IRANIAN HEALTHY VOLUNTEERS UNDER FASTING CONDITION

Objective: This study aims to compare a generic formulation of the drug erlotinib 150 mg tablet to the brand-name version to validate the analytical method and bioequivalence studies.Methods: Erlotinib hydrochloride tablets (test versus reference formulation) were compared in a randomized, two-period crossover study to determine their pharmacokinetic properties and bioequivalence in healthy Iranian volunteers. 14 d passed between each treatment during the washout period. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to analyze erlotinib, and the method validation is presented.Results: Over the range of 6.25-3200 ng/ml, the analytical method was verified as linear (R2= 0.998). The technique was also accurate and precise at various concentrations. The results showed that the pharmacokinetics of the two products were comparable. Following administration of the test and reference products, the geometric averages for (Area under the curve) AUC0-72, AUCinf, and maximum plasma concentration (Cmax) were 104.71 (90% CI, 93.39-117.40), 104.68 (90% CI, 93.47-117.23), and 104.85 (90% CI, 94.61-116.21), respectively. The outcomes fell within the permitted tolerance of 0.8 to 1.25.Conclusion: For the determination of erlotinib in plasma, the used analytical approach is accurate, precise, repeatable, and selective. Additionally, the bioequivalence research revealed no appreciable differences in pharmacokinetic characteristics between the reference and test products. Therefore, it is possible to assert that the generic erlotinib product and the reference product are bioequivalent.

Establishment and application for simultaneous determination method of atorvastatin and its active/toxic metabolites in rat plasma / 中国药房

OBJECTIVE To establish a method for simultaneous determination of atorvastatin （ATV） and its active metabolites 2-hydroxy atorvastatin acid （2-HAT）， 4-hydroxy atorvastatin acid （4-HAT） and toxic metabolite atorvastatin lactone （ALT） in rat plasma and apply it for pharmacokinetic study. METHODS LC-MS/MS method was adopted for analysis. The one-step precipitation method was used for processing plasma samples （plasma samples were pretreated by acidification to adjust pH value so as to prevent inversion of configuration）， gradient elution was used to analyze the samples， and the analysis time was 5 min. Electrospray positive ionization was adopted， and positive ion scanning was performed in multi-reaction monitoring. The m/z of quantified ion pairs of ATV and its metabolites such as 2-HAT， 4-HAT and ATL， and internal standard pitavastatin were 559.3→ 440.2， 575.2→440.3， 575.0→440.2， 540.9→448.2 and 422.2→290.0， respectively. After conducting a comprehensive methodological investigation of the analytical method， the concentrations of ATV and its metabolites 2-HAT， 4-HAT，and ATL were determined， and the pharmacokinetic parameters of ATV and its metabolites were calculated using the non- compartment model of WinNonlin 6.1. RESULTS The results of methodological validation showed that endogenous substances in blank plasma did not interfere with the determination of the components to be tested， and the standard curve had a good linear relationship； the lower limits of quantification for ATV， 2-HAT， 4-HAT and ATL were 0.5， 0.5， 0.25 and 0.063 nmol/L， respectively. The precision， accuracy， recovery， matrix effect and stability investigation were all in line with the requirements of biological analysis. Pharmacokinetic analysis showed that after intragastric administration in rats， ATV calcium metabolized rapidly， and was mainly exposed to blood circulation in the form of ATV and 2-HAT， with the lowest concentration of lactone-type metabolites. CONCLUSIONS The established method is precise， rapid and accurate for plasma concentration analysis of ATV and its active/toxic metabolites. The application of the method could help to fully elucidate the pharmacokinetic characteristics of atorvastatin calcium in rats.

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.

An emerging analytical tool for highly sensitive quantitative analysis based on liquid chromatography-multiple-reaction monitoring cubed (MRM3) / 中国药科大学学报

@#Liquid chromatography-multiple-reaction monitoring (LC-MRM) has been widely recognized as the golden standard for multiple components-targeted quantitative analysis of complicated matrices,with extensive applications for analysis in such fields as chemical drugs, traditional Chinese medicines and foods.Unfortunately, when facing the task of quantitatively analyzing trace chemical components in complex matrices, MRM suffers dramatically from the background noise or matrix interference, leading to undesirable sensitivity and selectivity in terms of the lower limits of quantification (LOQ) and detection (LOD).In recent years, MRM cubed (MRM3), also known as MS3 scan, has received much attention because of its unique ability to significantly improve detection selectivity and sensitivity attributing to the successive ion filtering function, enabling LC-MRM3 as an emerging analytical tool.In this review,our attention is devoted to: 1) the illustration of the principle for MRM3; 2) parameter settings; and 3) the application progress of LC-MRM3 in such fields as the pursuit of biomarkers, pharmaceutical analysis, forensic analysis, toxicological analysis, food chemistry, and environmental analysis, aiming to provide a promising analytical tool of LC-MRM3 advantageous in the quantification analysis of trace chemical components in complex matrices.

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.

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.

Pharmacokinetic study of small molecule inhibitor SYHA1809 in Beagle dogs / 中国药房

OBJECTIVE To study the pharmacokinetics of small molecule inhibitor SYHA1809 in Beagle dogs. METHODS LC-MS/MS method was adopted. Beagle dogs were randomly divided into single intravenous administration group （3.75 mg/kg）， single low-dose intragastric administration group （3.75 mg/kg）， single medium-dose intragastric administration group （7.5 mg/kg）， single high-dose intragastric administration group （15 mg/kg） and multiple intragastric administration group （7.5 mg/kg， once a day， for 7 consecutive days）， with 6 dogs in each group， half male and half female. The plasma samples of Beagle dogs were collected in each group according to the set time point， and underwent LC-MS/MS quantitative analysis after preprocessing. The pharmacokinetic parameters were calculated by using Phoenix WinNonlin 8.0 software using obtained data. RESULTS After intravenous injection， CL of SYHA1809 in Beagle dogs was （2.70±0.48） mL/（min·kg）， steady-state distribution volume was 0.757 L/kg， and t1/2 was （3.35±1.36） h； after single intragastric administration of low-dose， medium-dose and high-dose of SYHA1809， average tmax was （0.53±0.02） h， and the blood drug concentration increased with the increase of dose； after single intragastric administration of 3.75 mg/kg SYHA1809， the absolute bioavailability was 83.5%； within the dose range of 3.75-15 mg/kg， the increase in cmax and AUC of SYHA1809 was positively correlated with the dose； after intragastric administration of 7.5 mg/kg SYHA1809 for 7 consecutive days， the pharmacokinetic parameters of SYHA1809 were comparable to those of a single intragastric administration of the same dose， with no statistically significant difference （P＞0.05）. CONCLUSIONS SYHA1809 is absorbed rapidly in Beagle dogs， shows the dose-dependent blood concentration， high bioavailability， no obvious accumulation after multiple intragastric administration， and good pharmacokinetic behavior.

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.