Simultaneous determination of rosuvastatin and fenofibric acid in human plasma by LC-MS/MS with electrospray ionization: assay development, validation and application to a clinical study

A simple, sensitive and specific LC-MS/MS method for simultaneous determination of rosuvastatin (RST) and fenofibric acid (FFA) was developed and validated with 500 microL human plasma using carbamazepine as an internal standard (IS). The assay procedure involved a simple one-step liquid/liquid extraction of RST and FFA and IS from plasma into ethyl acetate. The organic layer was separated and evaporated under a gentle stream of nitrogen at 40 degrees C. The residue was reconstituted in the mobile phase and injected onto X-Terra MS C-18 column (4.6 mm x 50 mm, 5.0 microm). Separation of RST, FFA and IS was achieved with a mobile phase consisting of 0.05 M formic acid:acetonitrile (45:55, v/v) at a flow rate of 0.40 ml/min. The API-3000LC-MS/MS was operated under the multiple reaction-monitoring mode (MRM) using the electrospray ionization technique. Positive ion acquisition chromatographic run was used in the present method. Nominal retention times of RST, FFA and IS were 2.35, 4.70 and 2.32 min, respectively. Absolute recovery of RST, FFA and IS was 74, 61 and 69%, respectively. The lower limit of quantification (LLOQ) of RST and FFA was 1.00 ng/ml and 0.50 microg/ml, respectively. Response function was established for the range of concentrations 1.00-50.0 ng/ml and 0.50-20.0 microg/ml for RST and FFA, respectively, with a coefficient of determination (r2) of 0.999 for both the compounds. The inter- and intra-day precision in the measurement of RST quality control (QC) samples 5, 15, 400 and 800 ng/ml, were in the range 8.93-9.37% relative standard deviation (R.S.D.) and 1.74-16.1% R.S.D., respectively. Similarly, the inter- and intra-day precision in the measurement of FFA quality control (QC) samples 0.5, 1.5, 8.0 and 15.0 microg/ml, were in the range 9.78-11.6% relative standard deviation (R.S.D.) and 0.22-17.4% R.S.D., respectively. Accuracy in the measurement of QC samples for RST and FFA were in the range 88.1-108 and 87-115%, respectively, of the nominal values. RST and FFA were stable in the battery of stability studies, viz., bench-top, auto-sampler and freeze/thaw cycles. Stability of RST and FFA was established for 1 month at -80 degrees C. The application of the assay to a clinical study confirmed the utility of the assay.     

Development and validation of a LC-MS/MS method with electrospray ionization for determination of LASSBio-579 in rat plasma

A simple and sensitive LC-MS/MS analytical method was developed and validated for the determination of LASSBio-579 in plasma rat, using fluconazole as internal standard. Analyses were performed on a Shimadzu HPLC system using a Shimadzu C18 column and isocratic elution with acetonitrile-water (80:20, v/v), containing 0.4mM ammonium hydroxide and 0.2 mM acetic acid at a flow rate of 1.0 ml/min (split ratio 1:5). A Micromass triple quadrupole mass spectrometer, equipped with an electrospray ionization interface, operated in the positive mode. Plasma samples were deproteinized with acetonitrile (1:2) and 50 microl of the supernatant were injected into the system. The retention times of LASSBio-579 and IS were approximately 4.7 and 2.4 min, respectively. Calibration curves in spiked plasma were linear over the concentration range of 30-2000 ng/ml with determination coefficient >0.98. The lower limit of quantification was 30 ng/ml. The accuracy of method was within 15%. Intra- and inter-day relative standard deviations were less or equal to 13.5% and 6.4%, respectively. The applicability of the LC-MS/MS method for pharmacokinetic studies was tested using plasma samples obtained after intraperitoneal administration of LASSBio-579 to male Wistar rats. No interference from endogenous substances was observed, showing the specificity of the method developed. The reported method can provide the necessary sensitivity, linearity, precision, accuracy, and specificity to allow the determination of LASSBio-579 in pre-clinical pharmacokinetic studies.     

Development and validation of a selective and robust LC-MS/MS method for quantifying trimetazidine in human plasma

AIM： To develop and validate a liquid chromatography-tandem mass spectrometric method （LC-MS/MS） for quantifying trimetazidine in human plasma.METHODS： Sample preparation was based on extracted using acetonitrile only. Chromatography was performed on a C18 analytical column and the retention times were 1.9 and 2.6 min for trimetazidine and cetirizine （internal standard）, respectively. The ionization was optimized using ESI （ ＋ ） and enhanced selectivity was achieved using tandem mass spectrometric analysis via two MRM functions, m/z：267→m/z： 181 and m/z：389→m/z：201 for trimetazidine and cetirizine.[第一段]     

Development and validation of a selective and robust LC-MS/MS method for quantifying ilaprazole and its metabolite ilaprazole sulfone in human plasma

LC-MS/MS方法测定人血浆中艾普拉唑及其代谢产物艾普拉唑砜的浓度@谭志荣$Pharmacogenetics Research Institute, Institute of Clinical Pharmacology, Central South University!Changsha 410078, Hunan, China @张伟$Pharmacogenetics Research Institute, Institute of C     

A sensitive LC-MS/MS method for the quantification of fluticasone propionate in human plasma

A sensitive and selective LC-(APCI) MS/MS method capable of quantifying fluticasone propionate (FP) at levels down to 10 pg ml(-1) in human plasma is reported. The method was validated over a linear range from 10 to 1000 pg ml(-1) using a previously published solid-phase extraction procedure with a 13C3-labeled internal standard. The inter and intra batch precision (coefficient of variation) and accuracy (% bias) of the quality controls samples (20, 25, 50, 100, 200, 500 and 1000 pg ml(-1)) were less than 15 and 11%, respectively. The method is robust, rapid (analysis time of 2 min), selective and hence is ideally suited for pharmacokinetic investigations involving inhalation of therapeutic doses of FP.     

A highly sensitive LC-MS/MS method for the determination of 21-hydroxy deflazacort in nude mice plasma and its application to a pharmacokinetic study

In the current study, we established and validated a simple and sensitive liquid chromatography-tandem mass spectrometricmethod for the determination of 21-hydroxy deflazacort in nude mice plasma, and such a method was applied to a pharmacokinetic study. Using betamethasone as the internal standard, the plasma samples were pre-treated by precipitation with acetonitrile and then analyzed on a reversed-phase C₁₈ column (50 mm×2 mm, 5 μm) with a mobile phase consisting of acetonitrile and 4.0 mM ammonium formate (pH was adjusted to 3.5 with formic acid (40:60, v/v)). The analyte was detected by a triple quadrupole tandem mass spectrometer using electrospray, and multiple reaction monitoring was employed to select 21-hydroxy deflazacort at m/z 400.2/124.0 and betamethasone at m/z 393.3/147.0 in the positive ion mode. The calibration curves were linear (r>0.99) over the range of 0.5–400 ng/mL. The intra- and inter-day precisions and accuracies were 4.5%–10.1% and –1.7%~10.7% respectively. This method was successfully applied to a preclinical pharmacokinetic study of deflazacort on female nude mice administered with a single oral dose of 4 mg/kg deflazacort, and its pharmacokinetics was characterized by a two-compartment model with first-order absorption.     

LC-MS/MS法测定人血浆中加巴喷丁的浓度及其药动学研究

建立液相色谱串联质谱(LC-MS/MS)法测定人血浆中加巴喷丁的浓度并将其应用于人体药动学研究。取血浆样品经甲醇沉淀蛋白后,以甲醇0.2%甲酸水溶液(80∶20)为流动相,用Inertsil ODS-3 C18柱(50 mm×2.1 mm ID,3μm)分离,采用电喷雾离子源,以多反应监测(MRM)方式进行正离子检测,定量分析的离子反应分别为m/z 172→m/z 154(加巴喷丁)和m/z 130→m/z 71(内标二甲双胍)。加巴喷丁线性范围为40.8～8.16×103 ng.mL 1,定量限为40.8 ng.mL 1,每个样品测试时间仅2.2 min,日内、日间精密度(RSD)均小于12%,准确度(RE)在±6.4%范围内。应用此法研究了20名健康志愿者单剂量口服加巴喷丁胶囊600 mg后的药动学特点。该方法快速、专属、灵敏、适用性强,可应用于加巴喷丁的人体药动学研究。     

Development of a robust and sensitive LC-MS/MS method for the determination of adenine in plasma of different species and its application to in vivo studies

A simple, robust, and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the measurement of endogenous adenine in mouse, rat, cynomolgus monkey, and human plasma. A “surrogate analyte” strategy was adopted by employing [¹³C(U)]-adenine as the surrogate analyte. The plasma samples were processed by protein precipitation, and the extracted supernatant samples were subjected directly to LC-MS/MS analysis. The analysis was carried out in the negative ion detection mode using selected-reaction monitoring (SRM). The method achieved a lower limit of quantification (LLOQ) of 5.0 nM with a signal-to-noise ratio of 10. The intra- and inter-day assay coefficients of variation (CV) were ≤6.67% in rat plasma, and the mean recoveries and matrix effects across species and at various concentrations ranged from 88.8% to 104.2% and 86.0% to 110.8%, respectively. Using this methodology, the endogenous concentration of adenine in plasma of four species was found to range from 8.7 nM in human to 93.1 nM in cynomolgus monkey plasma. The assay was further applied to both an adenine pharmacokinetic study and a pivotal pharmacodynamic study evaluating the plasma concentration of adenine after a dose of 5′-deoxy-5′-methylthioadenosine (MTA).     

液相色谱-串联质谱法测定人血浆和尿液中培拉米韦的浓度及其在中国健康人体的药动学(英文)

目的建立测定人血浆和尿液中培拉米韦的LC-MS/MS法。方法 12名中国健康受试者单次静脉滴注培拉米韦三水合物氯化钠注射液,给药剂量为600 mg,采集血浆样本和尿液样本并测定其中培拉米韦的浓度。血浆样本以乙腈沉淀蛋白、尿液样本经直接稀释后,选用Synergi Hydro-RP 80A C18色谱柱(150 mm×2.0 mm,4μm),以甲醇︰0.5%甲酸=35︰65(V/V)为流动相,流速为0.4 m L·min-1。选用三重四极杆串联质谱仪的多重反应监测(MRM)扫描方式进行监测,电喷雾离子化源,正离子方式。使用Win Nonlin 6.3软件计算药动学参数。结果血浆和尿液中培拉米韦的线性范围分别为0.024 0~60.0 mg·L-1、0.400~1 000 mg·L-1;测定血浆中培拉米韦的日内、日间相对标准差(RSD)均小于8.0%,相对误差(RE)在±8.0%的范围以内,测定尿液中培拉米韦的日内、日间RSD均小于4.0%,RE在±10.0%的范围以内;提取回收率较高,且可重现;血浆和尿液样本中的内源性物质不干扰培拉米韦和内标的测定;培拉米韦在各种贮存条件下均较稳定。中国健康受试者单次静脉滴注培拉米韦600 mg后的主要药动学参数如下:ρmax为(41.1±5.3)mg·L-1,AUC0-t为(112.1±13.2)mg·h·L-1,AUC0-∞为(112.3±13.2)mg·h·L-1,t1/2为(3.28±1.15)h。36 h内,培拉米韦的尿液累积排泄率为(90.50±7.38)%。结论该方法快速、灵敏、专属性强、重现性好,适用于培拉米韦的人体药动学研究。     

液相色谱-串联质谱法测定人血浆中阿那罗唑及生物等效性

目的建立液相色谱-串联质谱(LC-MS/MS)法测定人血浆中阿那罗唑浓度,用于研究两种阿那罗唑片在人体内的生物等效性。方法以替硝唑为内标,色谱柱为Agilent TC-C18(4.6 mm×150 mm,5μm),流动相为乙腈∶0.2%甲酸水溶液=70∶30(V/V),采用电喷雾离子源(ESI)正离子模式,多反应监测模式进行定量分析。24例中国男性健康志愿者随机分为两组,每组12人,于不同周期分别单次口服受试制剂或参比制剂2 mg。采用LC-MS/MS法测定阿那罗唑血药浓度并用WinNonlin软件计算药动学参数。结果阿那罗唑线性范围为0.168 3～100 ng·mL-1,定量下限为0.168 3 ng·mL-1,日内及日间精密度、回收率、基质效应均符合生物样品测试要求。主要药动学参数为:受试制剂和参比制剂的ρmax分别为(39.6±6.9)、(39.8±7.6)ng·mL-1;tmax分别为(1.9±1.1)、(2.2±1.3)h;t1/2分别为(34.7±8.1)、(35.1±6.6)h;AUC0-∞分别为(1 738.9±425.8)、(1 725.7±468.0)ng·h·mL-1;受试制剂对参比制剂的相对生物利用度为(102.1±10.2)%。结论该方法简单、高效、灵敏,测得受试制剂与参比制剂主要药动学参数无显著差异,两种阿那罗唑片在人体内具有生物等效性。     

LC-MS/MS法测定人血浆中拉米夫定的质量浓度及生物等效性评价

目的建立人血浆中拉米夫定质量浓度的LC-MS/MS测定方法,并应用于拉米夫定片在健康人体内的生物等效性研究及评价。方法前处理方法采用沉淀蛋白法。分离选用Venusil ABS C18色谱柱,以甲醇-水-甲酸(体积比5.0∶95.0∶0.1)为流动相,采用多反应离子监测(multiple reaction monitoring,MRM)模式进行正离子检测。结果拉米夫定的线性范围为0.020 0~5.00 mg·L-1,定量下限为20μg·L-1。方法准确度为95.0%~102.4%,日内和日间精密度均不大于7.6%。结论本方法适用于拉米夫定人体生物等效性试验研究。24名健康受试者口服拉米夫定参比制剂和受试制剂后的药代动力学行为一致。     

Development and validation of a sensitive and robust LC-tandem MS method for the analysis of warfarin enantiomers in human plasma

A liquid chromatography-tandem mass spectrometry method (LC-MS-MS) was developed and validated for measuring warfarin (WAR) enantiomers (R-WAR and S-WAR) in human EDTA plasma. Liquid-liquid extraction using ethyl ether was used to extract the analytes from the plasma. Baseline resolution of S- and R-WAR as well as the internal standard enantiomers (S- and R-p-ClWAR, S-IS and R-IS) was achieved on a beta-cyclodextrin column with a mobile phase of acetonitrile-acetic acid-triethylamine (1000:3:2.5, v/v/v). The retention times are 6.9, 8.0, 7.0, and 7.9 min for S-WAR, R-WAR, S-IS and R-IS, respectively. The detection was by monitoring S- and R-WAR at m/z 307-->161 and S- and R-IS at m/z 341-->161 using (-) ESI. The standard curve range was 1-100 ng ml(-1) for both S- and R-WAR. The inter-day precision and accuracy of the quality control (QC) samples were <7.3% relative standard deviation (RSD) and <7.3% bias for S-WAR, and <6.5% RSD and <5.8% bias for R-WAR, respectively. Analyte stability during sample processing and storage were established. Method ruggedness was demonstrated by the reproducible performance from analysis of clinical samples.     

LC-MS/MS法同时测定人血浆中兰索拉唑与代谢产物的浓度及其药动学研究(英文)

目的建立同时测定人血浆中兰索拉唑及其代谢产物5’-羟基兰索拉唑和兰索拉唑砜的LC-MS/MS法。方法血浆样本用乙腈沉淀蛋白后,选用Zorbax SB-C18 Narrow-Bore色谱柱(150 mm×2.1 mm,5μm),以甲醇︰10 mmol.L-1乙酸铵(65︰35,V/V)为流动相,流速为0.4 mL.min-1。选用API3200型三重四极杆串联质谱仪的多重反应监测(MRM)扫描方式进行监测,电喷雾离子化源,负离子方式。结果兰索拉唑、5’-羟基兰索拉唑、兰索拉唑砜以及内标奥美拉唑的保留时间分别为2.63、1.56、2.21、2.30 min;血浆中兰索拉唑、5’-羟基兰索拉唑、兰索拉唑砜的线性范围分别为2.00～800、1.00～400、0.200～80.0μg.L-1(r>0.99),定量下限分别为2.00、1.00、0.200μg.L-1;日内、日间相对标准差(RSD)均小于8.0%;相对偏差(RE)均在±6.0%的范围以内;提取回收率较高,且可重现;兰索拉唑、5’-羟基兰索拉唑、兰索拉唑砜在各种贮存条件下均较稳定。该方法成功地应用于兰索拉唑肠溶片在中国健康人体内的药动学研究,兰索拉唑、5’-羟基兰索拉唑、兰索拉唑砜的ρmax分别为165～1400、15.8～177、10.2～530μg.L-1,AUC0-t分别为651～7 189、99.3～639、20.5～4 372μg.h.L-1。兰索拉唑及其代谢产物的药动学存在显著的个体间差异。结论该方法快速、灵敏、专属性强、重现性好,适用于兰索拉唑及其代谢产物的人体药动学研究。     

液相色谱-串联质谱法测定人血浆中瑞舒伐他汀钙浓度及临床药代动力学研究

目的：建立测定人血浆中瑞舒伐他汀钙的液相色谱．串联质谱法，考察瑞舒伐他汀钙在中国健康志愿者体内的药代动力学。方法：含有瑞舒伐他汀钙和氟伐他汀钠的血浆样品经液-液提取后，进行色谱分析，在三重四极杆串联质谱仪上，以多反应离子监测方式进行定量分析。结果：瑞舒伐他汀钙的定量下限为0．03ng／mL，线形范围为0．03～60ng／mL，精密度与准确度符合生物样品分析要求。结论：该方法操作简便、快速、灵敏度高，适合瑞舒伐他汀钙的临床药代动力学研究。     

Development and validation of a sensitive LC-MS/MS method for the determination of adefovir in human serum and urine

A sensitive and selective liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and validated for the determination of adefovir (PMEA) in human serum and urine. The analyte was separated on a Diamonsil C(18) column (250 mm x 4.6 mm i.d., 5 microm particle size) by isocratic elution with methanol-water-formic acid (20:80:0.1, v/v/v) at a flow rate of 0.6 ml/min, and analyzed by mass spectrometry in multiple reaction-monitoring mode. The precursor-to-product ion transitions of m/z 274-->162 and m/z 226-->135 were used to measure and quantify the analyte and internal standard (I.S.), respectively. The weighted (1/x(2)) calibration curve was linear over serum concentration range 1.25-160.00 ng/ml and urine concentration range 0.05-8.00 microg/ml, with a correlation coefficient (r) of 0.9992 and 0.9978, respectively. The lower limit of quantification in human serum was 1.25 ng/ml. The inter- and intra-day precisions (R.S.D.%) in both serum and urine were lower than 8.64%, the mean method accuracies and recoveries from spiked serum samples at three concentrations ranged from 96.3 to 102.0% and 56.5 to 59.3%, respectively. The serum extract was stable when stored for 24h. The developed method was successfully applied to determine PMEA in human serum and urine, and proved suitable to clinical pharmacokinetic study.     

Development and validation of a highly sensitive liquid chromatography/mass spectrometry method for simultaneous quantification of lenalidomide and flavopiridol in human plasma

Lenalidomide, an immunomodulatory agent, and flavopiridol, a broad cyclin-dependent kinase inhibitor, are active therapies for clinical use in genomic high-risk chronic lymphocytic leukemia. A high-performance liquid chromatographic assay with tandem mass spectrometric detection has been developed to simultaneously quantify lenalidomide and flavopiridol in human and mouse plasma to facilitate their combined clinical development. Samples were prepared by liquid-liquid extraction with acetonitrile (ACN)-containing internal standard, genistein, followed by evaporation of solvent and reconstitution in 95/5 H2O/ACN. Lenalidomide and internal standard were separated by reversed-phase liquid chromatography on a C-18 column using a gradient of H2O and ACN, each with 0.1% formic acid. Atmospheric pressure chemical ionization in positive ion mode with single reaction monitoring on a triple quadrupole mass spectrometer was applied to detect transitions of lenalidomide (260.06 > 149.10) and flavopiridol (402.09 > 341.02). Lower limits of quantification of lenalidomide and flavopiridol were 1 and 0.3 nM, respectively. Recoveries of lenalidomide and flavopiridol from human plasma ranged from 99% to 116% throughout their linear ranges. Within- and between-run precision and accuracy of replicate samples were all less than 15%. This is the most sensitive analytical method reported to date for both lenalidomide and flavopiridol. This sensitivity will enable late terminal phase concentration measurements and accurate pharmacokinetic parameter estimation in a planned clinical trial with lenalidomide and flavopiridol in patients with chronic lymphocytic leukemia.     

LC-MS/MS法同时测定洛匹那韦和利托那韦的血浆浓度

建立液相色谱-串联质谱法 (LC-MS/MS) 测定人血浆中洛匹那韦 (LPV)、利托那韦 (RTV) 的浓度。血浆样品经碱化沉淀蛋白后, 经乙酸乙酯液-液萃取, 以甲醇-0.1%甲酸水溶液 (80∶20) 为流动相, Agilent ZORBAX Eclipse XDB-C₁₈ (150 mm × 4.6 mm ID, 5 μm) 柱分离; 采用电喷雾电离源, 以多反应监测 (MRM) 方式进行正离子检测, 用于定量分析的离子对LPV为629.6→155.2, RTV为721.4→268.2, 内标替米沙坦 (TEL) 为515.2→276.2。测定血浆中LPV线性范围为62.5～10 000 ng·mL⁻¹, 检测限为15 pg·mL⁻¹, RTV的线性范围为12.5～2 000 ng·mL⁻¹, 检测限为8 pg·mL⁻¹, r均大于0.99。日内和日间精密度均小于15%, 提取回收率均大于75%。该法选择性强、灵敏度高、重现性好, 能同时快速、准确测定人血浆LPV和RTV浓度, 为临床治疗药物浓度监测 (TDM) 奠定基础。     

Rapid and sensitive LC-MS/MS method for determination of Pravastatin in human plasma

快速灵敏的LC-MS/MS方法检测人血浆中普伐他汀的浓度@张敏$Institute of Clinical Pharmacology, Central South University!Changsha 410078,Hunan,China @谭志荣$Institute of Clinical Pharmacology, Central South University!Changsha 410078,Hunan,China @周宏灏$Ins     

An improved LC-MS/MS method for quantitative determination of ilaprazole and its metabolites in human plasma and its application to a pharmacokinetic study

Aim： To improve and validate an analytical method based on liquid chromatography and electrospray ionization tandem mass spectrometry （LC-ESI-MS/MS） for the quantitative measurement of ilaprazole and its two metablites in human plasma. Methods： Separation of analytes and the internal standard （IS）, omeprazole, was performed on a Thermo HyPURITY C18 column （150×2.1 mm, 5 um） with a mobile phase consisting of 10 mmol/L ammonium formate water-acetonitrile solution （50：50, v/v） at a flow rate of 0.25 mL/min. The API4000 triple quadruple mass spectrometer was operated in multiple reactions monitoring mode via positive electrospray ionization interface using the transition m/z 367.2 → m/z 184.0 for ilaprazole, m/z 383.3 → m/z 184.1 for ilaprazole sulfone, m/z 351.2 → m/z 168.1 for ilaprazole thiol ether and m/z 346.2 → m/z 198.0 for omeprazole. Results： The method was linear over the concentration range of 0.23-2400.00 ng/mL for ilaprazole, 0.05-105.00 ng/mL for ilaprazole thiol ether and 0.06-45.00 ng/mL for ilaprazole sulfone. The intra- and inter-day precisions were all less than 15% in terms of relative standard deviation （RSD）, and the accuracy was within 15% in terms of relative error （RE） for ilaprazole, ilaprazole sulfone and ilaprazole thiol ether. The lower limit of quantification （LLOQ） was identifiable and reproducible at 0.23, 0.05 and 0.06 ng/mL with acceptable precision and accuracy for ilaprazole, ilaprazole sulfone and ilaprazole thiol ether, respectively. Conclusion： The validated method offered sensitivity and a wide linear concentration range. This method was successfully applied for the evaluation of the pharmacokinetics of ilaprazole and its two metabolites after single oral doses of 5 mg ilaprazole to 12 healthy Chinese volunteers.     

人血浆中乌苯美司液相色谱-质谱联用法快速测定及其药动学研究

目的 采用液相色谱-质谱联用法(LC-MS/MS)测定人血浆中乌苯美司的药物浓度,并应用于健康受试者体内药动学研究。方法 以文拉法辛为内标,血浆样品经甲醇沉淀蛋白后,以甲醇-醋酸铵(2 mmol·L^-1,含 0.2% 甲酸)水溶液(50:50)为流动相,Waters 公司 XTerra^® MS C₁₈(150 mm×4.6 mm,5 μm)色谱柱分离,体积流量为 900 μL·min^-1,每个样品的分析时间为 4.20 min。样品经电喷雾离子源正离子化后,通过三重四极杆串联质谱仪,在多反应监测模式下测定乌苯美司(m/z 309.3→120.2)和内标文拉法辛(m/z 278.2→215.1)的浓度。20 名受试者空腹口服乌苯美司胶囊 20 mg,250 mL温开水送服,于用药前和用药后10、20、30、45 min及1.0、1.5、2.0、3.0、4.0、6.0、8.0、10.0 h由肘静脉取血3 mL,制备血浆,按建立的LC-MS/MS法测定血浆中乌苯美司浓度,计算药动学参数。结果 乌苯美司的血浆质量浓度在1.0~2 500.0 ng·L^-1范围内线性关系良好,定量下限为 1.000 ng·mL^-1,批内、批间精密度(RSD)均在 2.2%~5.1%,相对偏差(RE)在±15% 范围内。乌苯美司血浆样品室温放置 24 h,反复冻融(-20℃)3 次及冰冻(-20℃)保存 50 d 的情况下均稳定。健康受试者空腹口服乌苯美司胶囊20mg后,血浆中乌苯美司的达峰浓度(C_max)为(1 375±298) ng·mL^-1, 药时曲线下面积(AUC_{0~10 h})为(2 106±296) h·ng·mL^-1,AUC_0~∞为(2 116±299) h·ng·mL^-1,半衰期(t_1/2)为(1.38±0.20)h,达峰时间(t_max)为(0.71±0.23) h。结论 建立的LC-MS/MS分析方法简便、选择性高、灵敏度高,可用于受试者空腹口服 20 mg 乌苯美司胶囊后血浆样品中乌苯美司的药动学研究,乌苯美司胶囊口服吸收迅速,0.71 h 后血药浓度可达峰值。