A Systematic Investigation of Complement and Coagulation-Related Protein in Autism Spectrum Disorder Using Multiple Reaction Monitoring Technology / 神经科学通报·英文版

Autism spectrum disorder (ASD) is one of the common neurodevelopmental disorders in children. Its etiology and pathogenesis are poorly understood. Previous studies have suggested potential changes in the complement and coagulation pathways in individuals with ASD. In this study, using multiple reactions monitoring proteomic technology, 16 of the 33 proteins involved in this pathway were identified as differentially-expressed proteins in plasma between children with ASD and controls. Among them, CFHR3, C4BPB, C4BPA, CFH, C9, SERPIND1, C8A, F9, and F11 were found to be altered in the plasma of children with ASD for the first time. SERPIND1 expression was positively correlated with the CARS score. Using the machine learning method, we obtained a panel composed of 12 differentially-expressed proteins with diagnostic potential for ASD. We also reviewed the proteins changed in this pathway in the brain and blood of patients with ASD. The complement and coagulation pathways may be activated in the peripheral blood of children with ASD and play a key role in the pathogenesis of ASD.

Content determination of ten flavonoids and alkaloids in Gleditsiae Sinensis Fructus, Gleditsiae Fructus Abnormalis, and Gleditsiae Spina / 中国中药杂志

To study the quality control of three traditional Chinese medicines derived from Gleditsia sinensis [Gleditsiae Sinensis Fructus(GSF), Gleditsiae Fructus Abnormalis(GFA), and Gleditsiae Spina(GS)], this paper established a multiple reaction monitoring(MRM) approach based on ultra-high performance liquid chromatography-triple quadrupole-linear ion-trap mass spectrometry(UHPLC-Q-Trap-MS). Using an ACQUITY UPLC BEH C_(18) column(2.1 mm × 100 mm, 1.7 μm), gradient elution was performed at 40 ℃ with water containing 0.1% formic acid-acetonitrile as the mobile phase running at 0.3 mL·min~(-1), and the separation and content determination of ten chemical constituents(e.g., saikachinoside A, locustoside A, orientin, taxifolin, vitexin, isoquercitrin, luteolin, quercitrin, quercetin, and apigenin) in GSF, GFA, and GS were enabled within 31 min. The established method could quickly and efficiently determine the content of ten chemical constituents in GSF, GFA, and GS. All constituents showed good linearity(r>0.995), and the average recovery rate was 94.09%-110.9%. The results showed that, the content of two alkaloids in GSF(2.03-834.75 μg·g~(-1)) was higher than that in GFA(0.03-10.41 μg·g~(-1)) and GS(0.04-13.66 μg·g~(-1)), while the content of eight flavonoids in GS(0.54-2.38 mg·g~(-1)) was higher than that in GSF(0.08-0.29 mg·g~(-1)) and GFA(0.15-0.32 mg·g~(-1)). These results provide references for the quality control of G. sinensis-derived TCMs.

Simultaneously quantitative analysis of 35 components in gualoupi injection using hydrophilic interaction liquid chromatography tandem mass spectrometry / 药学学报

A hydrophilic interaction chromatography tandem mass spectrometry method was developed for simultaneous quantification of 35 components in gualoupi injection. The analytes were separated with an ACQUITY XBridge Amide column using 20 mmol·L-1 ammonium formate aqueous solution (pH 3.0) as mobile phase A and 20 mmol·L-1 ammonium formate (pH 3.0)∶acetonitrile (1∶9) as mobile phase B for gradient elution. Mass spectrometry with dynamic multiple reaction monitoring and external standard method were used for quantitative analysis. A total of 35 components were determined in 10 batches of gualoupi injection. The results showed that the 35 compounds had a good linear relationship within their respective concentration ranges with the correlation coefficients (R2 > 0.998 0), the recoveries ranged from 76.6% to 118.5%. The results showed that γ-aminobutyric acid, trigonelline, alanine, threonine, homoserine, citrulline, and leucine were abundant in gualoupi injection, while nicotinamide, methylsuccinic acid, cytosine and choline account for a low percentege. The present study provides an important reference for elucidation of the effective material basis and the improvement of quality standard of gualoupi injection.

Quantitative determination of multi-class bioactive constituents for quality control of Yiqi Jiangzhi Granules / 中草药·英文版

Objective: To establish a reliable and sensitive method for evaluating quality of Yiqi Jiangzhi Granules (YQJZG). Methods: Ultra performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) was employed for simultaneous determination of eight marker components. Separation was performed on an AQUITY UPLC® HSS T3 column, the mobile phase consisted of acetonitrile as the organic phase and 0.1% (volume percentage) formic acid as the aqueous. Eight marker components, ginsenoside Rg1 (GRg1), ginsenoside Re (GRe), ginsenoside Rb1 (Gb1), typhaneoside (TEO), isorhamnetin-3-O-neohespeidoside (IN), hesperidin (HPD), aurantio-obtusin-6-O-β-D-glucoside (AG) and curcumin (CCM), were detected by multiple reaction monitoring (MRM) mode. The Chinese Pharmacopoeia (2020 edition) was regarded as the guidance document for this method validation. Results: The method showed good linearity (R

An ultra-robust fingerprinting method for quality assessment of traditional Chinese medicine using multiple reaction monitoring mass spectrometry / 药物分析学报

Chromatographic fingerprinting has been perceived as an essential tool for assessing quality and chemical equivalence of traditional Chinese medicine.However,this pattern-oriented approach still has some weak points in terms of chemical coverage and robustness.In this work,we proposed a multiple reaction monitoring(MRM)-based fingerprinting method in which approximately 100 constituents were simultaneously detected for quality assessment.The derivative MRM approach was employed to rapidly design MRM transitions independent of chemical standards,based on which the large-scale finger-printing method was efficiently established.This approach was exemplified on QiShenYiQi Pill(QSYQ),a traditional Chinese medicine-derived drug product,and its robustness was systematically evaluated by four indices:clustering analysis by principal component analysis,similarity analysis by the congruence coefficient,the number of separated peaks,and the peak area proportion of separated peaks.Compared with conventional ultraviolet-based fingerprints,the MRM fingerprints provided not only better discriminatory capacity for the tested normal/abnormal QSYQ samples,but also higher robustness under different chromatographic conditions(i.e.,flow rate,apparent pH,column temperature,and column).The result also showed for such large-scale fingerprints including a large number of peaks,the angle cosine measure after min-max normalization was more suitable for setting a decision criterion than the unnormalized algorithm.This proof-of-concept application gives evidence that combining MRM tech-nique with proper similarity analysis metrices can provide a highly sensitive,robust and comprehensive analytical approach for quality assessment of traditional Chinese medicine.

Determination of 53 pesticide residues in different category of Fritillaria by QuEChERS and GC-MS/MS / 中草药

Objective: To establish a method for simultaneous determination of 53 kinds of pesticides residual in different category of Fritillaria by using QuEChERS and gas chromatography tandem mass spectrometry, and applying to 193 batches sample screening. Methods: The forbidden, restricted and commonly used pesticides were selected as detecting indexes according to the result of this investigation. The samples were prepared by QuEChERS, and quantitative analysis was carried out by GC-MS/MS multiple-reaction monitoring (MRM) model. There were three supplemental levels for determining recoveries and RSD. Results: The results showed that all the 53 pesticides had good linearity in certain ranges with the correlation coefficients (R) higher than 0.997 8. The recoveries of more than 86.8% pesticides were ranged from 60% to 140% at three supplemental levels (1×LOD, 2×LOD, and 10×LOD), with the RSDs less than 15%. The LOD ranged of all pesticides were below 0.01 mg/kg. The result of 193 batches sample screening showed that 91 batches sample were detected 14 pesticides, and the detection rate was 47.2%. Conclusion: The detecting indexes is meaningful and the developed method is simple, rapid, sensitive, and reliable for screening multiple pesticide residues in different category of Fritillaria. The result has certain reference value for the cultivation and circulation supervision of different category of Fritillaria.

Rapid chemical profiling of Artemisiae Scopariae Herba using reversed phase liquid chromatography-hydrophilic interaction liquid chromatography-predictive multiple reaction monitoring / 中国中药杂志

Chemical profiling of a given herbal medicine( HM) is the prerequisite for clarifying the effective material basis and therapeutic mechanisms,and it is an important integral part of traditional Chinese medicine chemical biology( TCMCB). In current study,we aimed to propose a new strategy for fast chemical characterization of HM by using reversed phase liquid chromatography-hydrophilic interaction chromatography-predictive multiple reaction monitoring( RPLC-HILIC-p MRM),and Artemisiae Scopariae Herba was employed in this study to illustrate the entire strategy. In response to wide polarity spanning of the diverse chemical clusters in Artemisiae Scopariae Herba,RPLC and HILIC were coupled in series to retain and separate hydrophilic and hydrophobic components simultaneously by identifying the characteristics of chromatographic separation. Most of the chemical constituents in traditional Chinese medicine can be predicted by summarizing the results of chemical constituents of the same genera and introducing primary metabolites and possible substitution reaction types. Therefore,we constructed predictive ion pairs to rapidly identify the chemical constituents of Artemisiae Scopariae Herba. After comparison with control products,discussion on fragmentation pattern,and access to relevant information from literature and databases,a total of 139 components were detected and structurally annotated by matching the obtained spectral data with the information of authentic compounds. Above all,RPLC-HILIC-p MRM could be used as an eligible analytical tool for the chemical profiling of HMs.

Screening for potential bioactive components of Yin-zhi-huang using high bilirubin HepaRG cells incubating with serum from animals / 药学学报

A hyper-bilirubin cell model was established for its relevance to the pathological state of jaundice in human. This model was used to screen for the pharmacological components of Yin-Zhi-huang (YZH). Total bilirubin, indirect bilirubin in cells, and direct bilirubin in extracellular fluid were quantified after HepaRG cells were incubated with serum from rats injected with multiple components of YZH. Cellular uptake was determined by dynamic multiple reaction monitoring (DMRM) using LC-MS/MS. We found that the stable hyper-bilirubin HepaRG cell model could be established by incubating cells with 40 μg·mL-1 bilirubin and 50 μg·mL-1 probenecid. When the hyper-bilirubin cell model was incubated with serum from rats of YZH injection, there were 52.4% and 60.1% decrease in intercellular total bilirubin and indirect bilirubin, respectively, and 52.5% increase in extracellular direct bilirubin. Using DMRM mode, 53 components could be determined, and 8 potential bioactive candidates were identified from the serum. This method could be used to screen for bioactive metabolites of YZH. This strategy is simple, highly active, sensitive and specific, providing a new method for high throughput screening of therapeutic or toxic metabolites from traditional Chinese medicine. The regulations of Ethics Committee in the First Hospital of Lanzhou University were abided in the rat experiment of this study.

Fingerprint and multi-ingredient quantitative analyses for quality evaluation of hawthorn leaves and Guang hawthorn leaves by UPLC-MS

ABSTRACT This paper aimed to evaluate the quality of hawthorn leaves and Guang hawthorn leaves by an UPLC-MS method from two aspects, fingerprint analysis and multi-ingredient quantification. Chromatographic separation was carried out on an UPLC system, the standardized characteristic fingerprints was established by Similarity Evaluation System for chromatographic fingerprinting of traditional Chinese medicine and cluster analysis. Eight components were simultaneously determined by mass spectrometry in multiple reaction-monitoring mode. The method was validated in terms of linearity (R2 > 0.9971), intraday and interday precision (RSD < 2.0%), repeatability (RSD < 2.3%), stability (RSD < 2.5%) and recovery (96.2-103.8%). The developed method was successfully applied to the quality evaluation between hawthorn leaves and Guang hawthorn leaves, and there were differences in the component and the content, hawthorn leaves and Guang hawthorn leaves cannot substitute each other in clinical medication.

Determination of ten mycotoxins in food by HPLC-MS/MS / 国际药学研究杂志

Objective: To establish sample preparation and high performance liquid chromatography combined with electro- spray ionization tandem mass spectrometry(HPLC-MS/MS)methods for simultaneous determination of 10 mycotoxins in food. Meth- ods: This work established sample preparation method for mycotoxins in food using accelerated solvent extraction and solid phase ex- traction for solid food,using gel permeation chromatography for liquid food. Furthermore,it simultaneously identified and quantified 10 mycotoxins(aflatoxin M1,aflatoxin B1,aflatoxin B2,aflatoxin G1,aflatoxin G2,neosolaniol,deoxynivalenol,nivalenol,3- acetyldeoxynivalenol,15-acetyldeoxynivalenol)in food using HPLC-MS/MS. Separation and quantification were performed in both pos- itive and negative modes under multiple reaction monitoring(MRM)in a single run. Results: The results indicated as follows:high correlation coefficients(r≥0.999)of ten mycotoxins were obtained within their respective linear ranges and the detection limits for them ranged from 0.006 to 1 μg/L. The average recoveries were between 61.99% and 103.97%,with a relative standard deviation (RSD)varying from 0.76% to 10.63%. Conclusion: This method is rapid,accurate and highly sensitive for quantitative analysis and quality monitoring of mycotoxins in solid and liquid food.

Ultra Performance Liquid Chromatography-Tandem Mass Spectrometric Method for Detection of Pork Peptide Biomarkers / 分析化学

The samples of muscular tissue from pork,beef and lamb which were closely related in the genetic relationship were analyzed by ultra performance liquid chromatography-tandem mass spectrometric (UPLC-MS) technique.The specific peptide biomarkers of pig meat species were found and confirmed.Proteins from three pure meat samples were extracted and digested using trypsin,the digested proteins were identified by UPLC-triple time-of-flight (TOF)-MS,and the total ion chromatogram (TIC) was searched and analyzed against the UniProt database.Three high abundant homologous proteins of three species and 8 potential peptide biomarkers of pork were found.A multiple reaction monitoring (MRM) QTRAP-MS method was established to confirm the specificity of potential peptide biomarkers.As a result,five peptide biomarkers of pig species meat were confirmed,three of which were not reported.

Simultaneous determination of 10 active components in Xintong Oral Liquid by HPLC-MS/MS / 中草药

Objective: To establish an HPLC-MS/MS method for the simultaneous determination of ferulic acid, tetrahydroxystilbene glucoside, puerarin, calycosin-7-glucoside, naringin, protocatechuic aldehyde, salvianolic acid B, icariin, tanshinone IIA, and synephrine in Xintong Oral Liquid (XOL). Methods: The analysis was performed on Phenomenex Luna-C18 column (250 mm × 4.6 mm, 5 μm) by gradient elution of acetonitrile-mehanol-0.02 mol/L ammonium acetate. The flow rate was 0.9 mL/min. MS conditions: electrospray ionization (ESI) and multiple reaction monitoring (MRM) were adopted, the detected peak areas of ion pairs were used for quantitative determination. Results: The linear ranges of ferulic acid, tetrahydroxystilbene glucoside, puerarin, calycosin-7-glucoside, naringin, protocatechuic aldehyde, salvianolic acid B, icariin, tanshinone IIA, and synephrine were 15.22-15 220 (r = 0.999 3), 19.52-19 520 (r = 0.999 4), 25.41-25 410 (r = 0.999 5), 35.27-35 270 (r = 0.999 2), 30.28-30 280 (r = 0.999 4), 50.11-50 110 (r = 0.999 3), 20.33-20 330 (r =0.999 2), 25.22-25 220 (r = 0.999 6), 25.36-25 360 (r = 0.999 3), and 30.29-30 290 ng/mL (r = 0.999 2). The average recoveries (n = 6) were 98.15% (RSD = 1.04%), 101.84% (RSD = 0.98%), 99.86% (RSD = 0.75%), 101.08% (RSD = 0.87%), 100.52% (RSD =1.31%), 100.67% (RSD = 1.27%), 100.46% (RSD =1.64%), 99.43% (RSD =1.48%), 100.81% (RSD = 0.67%), and 98.37% (RSD =1.16%), respectively. The contents of 10 batches of the 10 active components were 0.294-0.319, 0.640-0.665, 4.671-4.699, 0.244-0.264, 2.211-2.231, 0.180-0.201, 0.306-0.324, 1.540-1.564, 0.504-0.522, and 0.809-0.829 mg/mL. Conclusion: This method is simple and rapid, and can be used for the quality control of XOL with satisfactory separation and repeatability.

Evaluation of regulation of Salvia miltiorrhiza and Panax ginseng on rat liver CYP450 using multiple reaction monitoring / 中草药

Objective: To establish a new specific and high-throughput method for CYP450 quantification, and to investigate the effect of drugs on rat liver CYP450 using Salvia miltiorrhiza and Panax ginseng as tool drugs. Methods: Mass spectrometry with multiple reaction monitoring (MRM) was applied to quantify nine rat liver enzyme CYP450 isoforms from the rat model with S. miltiorrhiza and P. ginseng. With QconCAT heavy peptides as internal standard, we aimed to assess the effects of S. miltiorrhiza and P. ginseng on CYP450 isoforms. Results: The relative standard deviation and relative error of this method were less than 5.9% and 6.8%, respectively, with good linearity (r2>0.9). Nine CYP450s isoforms (CYP1A1, CYP1A2, CYP2B1, CYP2B2, CYP2C6, CYP2C11, CYP3A1, CYP3A2, and CYP17A1) in rat liver microsome treated with S. miltiorrhiza and P. ginseng were also quantified. Compared with the control, S. miltiorrhiza downregulated the expression levels of CYP1A1, CYP2B2, CYP3A2, CYP2C11, and CYP17A1, while upregulated CYP1A2 and CYP2B1. For the effects of P. ginseng, the expression of CYP1A1 and CYP2B2 was decreased, while CYP1A2, CYP2B1, CYP3A2, CYP2C11, and CYP17A1 were increased. Conclusion: We successfully construct a method with MRM to quantify rat liver CYP450 isoforms. And we firstly quantify CYP2B1, CYP2B2, and CYP17A1 in rat liver. The results reveal the regulation of CYP450 by S. miltiorrhiza and P. ginseng, which could provide clinical application for drug compatibility in practice, and avoid adverse drug reactions.

Simultaneous determination of four Sudan dyes in rat blood by UFLC-MS/MS and its application to a pharmacokinetic study in rats☆ / 药物分析学报

A rapid and sensitive method based on ultrafast liquid chromatography-tandem mass spectrometry was developed and validated for simultaneous determination of Sudan Ⅰ, Sudan Ⅱ, Sudan Ⅲ, and Sudan Ⅳ levels in rat whole blood. Cleanert C18 mixed-mode polymeric sorbent was used for effective solid-phase extraction cleanup. Separation was carried out on a reversed-phase C18 column (100 mm × 2.1 mm, 1.8 μm) using 0.1% (v/v) formic acid in water/0.1% (v/v) formic acid in acetonitrile as the mobile phase in gradient elution. Quantification was performed by an electrospray ionization source in the positive multiple reaction monitoring mode using D5-Sudan I as the internal standard. Calibration curves showed good linearity between 0.2 and 20.0 μg/L, with correlation coefficients higher than 0.9990. The average recovery rates were between 93.05% and 114.98%. The intra- and inter-day relative standard deviations were within 6.2%. The lower limit of quantification was 0.2 μg/L. All the analytes were found to be stable in aseries of stability studies. The proposed method was successfully applied to a pharmacokinetic study of four Sudan dyes after oral administration to rats.

Quantitative Determination of Sildenafil in Aphrodisiacs by LC-MS / 医药导报

Objective To establish a method for the quantitative determination of sildenafil in aphrodisiacs by liquid chromatography-mass spectrometry (LC-MS). Methods Chromatography was carried on a Waters BEH C18 column (50 mmí2. 1 mm,1. 7 μm) with the column temperature being 35 ℃ and 0. 02 mol·L-1 ammonium acetate water solution (containing 0. 1% acetic acid)-acetonitril (7030) as the mobile phase at a flow rate of 0. 2 mL·min-1 . Determination was performed by multiple reaction monitoring mode in two channels,475→100,475→283,using electrospray ionization in positive ion mode. Results Sildenafil had a good linear relationship in the range of 0. 1986-1. 986 ng with the linear regression equation being Y=27 750X+15 232 (r=0. 995 2). The average recovery was 96. 6% with RSD being 1. 8% (n=9). The limits of quantitation and detection were 0. 04 ng and 0. 01 ng,respectively. Conclusion The determination results of 10 batches of samples show that the method is sensitive and accurate and can be used as an appropriate technique to detect sildenafil in aphrodisiacs.

Determination of 12 kinds of pesticide residues in Fritiliariae Thunbergii Bulbus by HPLC-MS / 中草药

Objective: To develop an analysis method based on N-propylethylenediamine (PSA)-HPLC-QQQ-MS/MS for the determination of 12 kinds pesticide residues in Fritiliariae Thunbergii Bulbus and to quantify them in 20 batches of Fritiliariae Thunbergii Bulbus produced in various places in Zhejiang province. Methods: Fritiliariae Thunbergii Bulbus samples were extracted with acetonitrile and purified by the small column of PSA. The prepared samples were analyzed by HPLC-QQQ-MS/MS in multiple reaction monitoring (MRM) mode, and the pesticides were qualitified by the internal standard method. Results: All the 12 pesticides showed good linearities in their reasonable range (r = 0.9986-0.9998), and the average recoveries of all the pesticides were in the range of 68.1%-108.0% at three spiked levels of 90, 300, and 900 ng/mL. The RSD values were in the range of 1.1%-6.1%, and the LODs of each pesticide were all in the range of 0.08-1.0 μg/kg. Conclusion: The method is suitable for the multiresidues analysis of pesticides in Fritiliariae Thunbergii Bulbus simultaneously and the quality of Fritiliariae Thunbergii Bulbus is basically good for the safty although it contains a trace of several pesticide residues.

Simultaneous determination of azathioprine and its metabolite 6-mercaptopurine in human plasma using solid phase extraction-evaporation and liquid chromatography–positive electrospray tandem mass spectrometry.

A simple, rapid, specific, sensitive and liquid chromatography coupled with tandem mass spectrophotometric method was developed and validated for the estimation of azathioprine and its metabolite 6-mercaptopurine in human plasma by using lamivudine and 6-mercaptopurine D3 as the internal standard. Azathioprine and 6-mercaptopurine were extracted from human plasma by solid-phase extraction (SPE)-Evaporation method, using Oasis MCX cartridge for cleaning procedure. The stationary phase was chromatographed on a ZORBAX SB CN, (75X50 mm, 5 μ) column where as mobile phase constitutes of acetonitrile: 2mM ammonium acetate (70:30 v/v) at a flow rate of 0.800 ml/min. The detection was performed with an Applied Biosystems Sciex API 4000 mass spectrome-ter by multiple reaction monitoring (MRM). The method validation proofs were carried out as per the USFDA guidelines as described, showing a linearity system (r2 > 0.99) over a range of 2.455 ng/mL to 106.568 ng/mL for azathioprine and 1.165 ng/mL to 101.143 ng/mL concentrations for 6-mercaptopurine and a recovery shows 99.36% and 100.44% for azathioprine and 6-mercaptopurine respectively. The results show that this proposed approach is effective and can be applied to the extraction and analysis of other pharmaceutical compounds.

Simultaneous determination of azathioprine and its metabolite 6-mercaptopurine in human plasma using solid phase extraction-evaporation and liquid chromatography–positive electrospray tandem mass spectrometry.

A simple, rapid, specific, sensitive and liquid chromatography coupled with tandem mass spectrophotometric method was developed and validated for the estimation of azathioprine and its metabolite 6-mercaptopurine in human plasma by using lamivudine and 6-mercaptopurine D3 as the internal standard. Azathioprine and 6-mercaptopurine were extracted from human plasma by solid-phase extraction (SPE)-Evaporation method, using Oasis MCX cartridge for cleaning procedure. The stationary phase was chromatographed on a ZORBAX SB CN, (75X50 mm, 5 μ) column where as mobile phase constitutes of acetonitrile: 2mM ammonium acetate (70:30 v/v) at a flow rate of 0.800 ml/min. The detection was performed with an Applied Biosystems Sciex API 4000 mass spectrome-ter by multiple reaction monitoring (MRM). The method validation proofs were carried out as per the USFDA guidelines as described, showing a linearity system (r2 > 0.99) over a range of 2.455 ng/mL to 106.568 ng/mL for azathioprine and 1.165 ng/mL to 101.143 ng/mL concentrations for 6-mercaptopurine and a recovery shows 99.36% and 100.44% for azathioprine and 6-mercaptopurine respectively. The results show that this proposed approach is effective and can be applied to the extraction and analysis of other pharmaceutical compounds.

A selective method for the qualitative determination of paroxetine in forensic biological samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Paroxetine is a schedule H antidepressant drug. It has occasionally been implicated in lethal overdoses. To identify and estimate the level of this drug in toxicological samples is a forensic challenge. Attempts have been made in the past to extract and detect paroxetine in blood samples by using a variety of techniques such as gas chromatography, gas chromatography-mass spectrometry, high pressure liquid chromatography, liquid chromatography-mass spectrometry, etc. However, no studies have been reported in other biological samples. In this study, an attempt has been made to identify paroxetine in biological samples by liquid chromatography-tandem mass spectrometry in multiple reaction monitoring mode at 330.15192.11. The product ion spectra proved to be very helpful in identification of the drug. Furthermore, multiple reaction monitoring (MRM) enhances the reliability and specificity of the method. The use of modified mobile phase produces good quality of qualifier ions. This method appears to be simple, sensitive, specific, and reliable.

Detemination of Organochlorine Pesticides in Drinking Water by Gas Chromatography-Mass Spectra-Mass Spectra / 环境与健康杂志

Objective To develop a method for the determination to organochlorine pesticides by gas chromatography-mass spectra-mass spectra.Methods The temperature of inlet was 250 ℃,the injection volume was 1 ?l,without split injection.The temperature of EI source was 300 ℃,the ionization energy was 70 eV,solvent delay time was 3.75 min,transfer line temperature was 280 ℃.181,235,246(m/z)were selected as parent ion,and 145,165,176(m/z)were sub ion.Results In the range of 0-50 ?g/L,every component had a good linearity,r≥0.99,the limit of detection≤0.01 ?g/L.Its average rate of recovery was in the range of 86.1%-101.8%,and the relative standard deviations(RSDs) were between 4.41%-8.07%.Conclusion Gas chromatography-mass spectra-mass spectra is more precise for the qualitative and quantitative determination of trace organochlorine pesticides residues in drinking water.