Development and validation of a LC/MS/MS method for 6-keto PGF1α, a metabolite of prostacyclin (PGI₂)

A sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was developed for the quantitation of 6-keto PGF_1α in human urine and plasma. Prostacyclin (PGI₂) is a locally acting prostanoid, which mediates vasorelaxation and inhibition of platelet aggregation. 6-Keto PGF_1α is the most-immediate metabolite of PGI₂.Samples were spiked with an internal standard (6-keto PGF_1α-d₄), purified by immuno-affinity chromatography and selected reaction monitoring (SRM) was performed.Analytical validation of the 6-keto PGF_1α assay was performed in urine. This included an assessment of assay precision, recovery, stability, sensitivity and linearity. Urinary 6-keto PGF_1α concentrations were also correlated to urinary 2,3-dinor-6-keto PGF_1α (PGIM) concentrations using urine samples collected from 16 healthy volunteers. The mean concentration of 6-keto PGF_1α in urine (mean ± SD) was 92 ± 51 pg/ml or 168 ± 91 pg/mg creatinine. Overall, there was a statistically significant correlation between urinary 6-keto PGF_1α and PGIM (r² = 0.55, p ≤ 0.001; slope = 2.7; y-intercept = 130). However, PGIM was approximately 3-fold more abundant than 6-keto PGF_1α in urine. In addition, 6-keto PGF_1α concentrations were measured in EDTA plasma samples obtained from 7 healthy donors. The mean concentration of 6-keto PGF_1α in plasma was 1.9 ± 0.8 pg/ml (±SD).     

LC/MS/MS定性定量检测地沟油中的胆固醇

目的探讨采用LC/MS/MS定性定量检测技术测定地沟油中胆固醇的含量。方法采用MRM-IDA-EPI的增强子离子扫描模式对检测样品进行综合分析,将获取的数据谱库进行检索,再依据匹配度来辨别化合物的真伪,并以此来排除假阳性的可能性,进而实现一次进样获取地沟油的胆固醇的定量、定性数据。结果通过本文实验研究结果表明,此方法所计算出来的最低定量限为50ng/mL,而通过添加基质样品与未添加前标准溶液进行对比分析,经验证法计算出其回收率在90%左右。从结果中我们发现,胆固醇含量在地沟油中的含量要比新植物油中低。结论因此,如果将胆固醇做为衡量地沟油的一个重要指标,其必将为鉴定地沟油提供有利的证据。     

LC/MS/MS与GC/MS法分析鉴定小鼠尿中沙美特罗的代谢产物

目的:鉴定沙美特罗在小鼠尿中的主要代谢产物.方法:ig给药后,收集小鼠尿液,经固相提取,葡萄糖醛酸酶水解,进行LC/MS/MS分析和硅烷化后进行GC/MS分析同时分离鉴定沙美特罗代谢产物.结果和结论:在给药后尿样中发现沙美特罗原型和4种代谢产物M1～M4,其结构推测为19-羟基沙美特罗(M1)、2-羰基沙美特罗(M2)、19-羰基沙美特罗(M3)和19-羟基-8-甲氧基沙美特罗(M4).     

LC–MS/MS assay for olanzapine in human plasma and its application to a bioequivalence study

This paper describes a selective and sensitive assay for the determination of olanzapine (OLZ) in human plasma based on liquid chromatography–tandem mass spectrometry (LC–MS/MS). The analyte and quetiapine as internal standard (IS) were extracted from 200 μL plasma via solid phase extraction on Waters Oasis HLB cartridges. Chromatographic separation was achieved on an ACE 5C18-300 column (100 mm×4.6 mm, 5 μm) under isocratic conditions in a run time of 3.5 min. Mass spectrometric detection involved electrospray ionization in the positive ion mode followed by multiple reaction monitoring (MRM) of the transitions at m/z 313/256 for OLZ and m/z 384/253 for the IS. The assay was linear in the range 0.10–40.0 ng/mL with a lower limit of quantitation and limit of detection of 0.10 and 0.012 ng/mL, respectively. Intra- and inter-day precision (as coefficient of variation) and relative recovery were <5.0% and >90%, respectively. The method was successfully applied to a bioequivalence study of 5 and 10 mg OLZ disintegrating tablets in 40 healthy Indian males with reproducibility by incurred sample reanalysis in the range ?7.43 to 8.07%.     

LC/MS/MS法测定人血浆中罗红霉素的血药浓度

目的建立LC/MS/MS法测定人血浆中罗红霉素的浓度。方法采用Diamonsil C18色谱柱,流动相甲醇-水-甲酸(75∶25∶0.5),流速为0.5mL·min-1。质谱检测方式:SIM。克拉霉素为内标,血浆样品用乙醚提取浓集,进行LC/MS/MS分析。结果本方法在0.1～40.0μg·mL-1内线性关系良好(r=0.9997),平均回收率87.6%,日内和日间RSD<10%。结论本方法快速、准确,适用于罗红霉素的临床药动学研究和血药浓度检测。     

HPLC/MS/MS联用技术测定全血中的瑞芬太尼

目的:建立全血中瑞芬太尼的HPLC／MS／MS测定方法,并测定围麻醉期患者体内瑞芬太尼的血药浓度。方法:全血样品中加入枸橼酸芬太尼作内标,用1-氯丁烷进行提取。以乙腈与三氯甲烷(V乙腈:V三氧甲烷= 1:1)混合液加乙酸铵(2 mmol·L-1)为流动相,色谱柱为Intersil ODS-3(50 mm×2．1 mm,3μm),流速0．3 mL·min-1。三级四极杆质谱采用正离子模式,离子采集方式为多反应监测模式(MRM),离子源温度200℃,离子源电离电压为5 000 V,雾化气流速8 L·min-1。采集离子(母离子／子离子)为瑞芬太尼377／228,芬太尼337／188。结果:瑞芬太尼在0．5～50．0 ng·mL-1浓度范围内呈良好的线性(r=0．9994)。日内、日间精密度均在15％以内,提取回收率大于67．3％,方法回收率在95．0％～97．6％。结论:本方法灵敏、准确,适合瑞芬太尼的体内分析。     

HPLC/MS/MS法测定人血浆中麦考酚酸浓度

目的 建立测定人血浆中麦考酚酸(免疫抑制剂)含量的HPLC/MS/MS方法 .方法 血浆样品经乙腈沉淀蛋白后,以15 mmol·L-1醋酸铵-甲醇梯度洗脱,用Agilent Zorbax Eclipse XDB-C18色谱柱,通过电喷雾离子化三重四极杆串联质谱,经多反应监测模式检测,m/z321.2→m/z 303.0(麦考酚酸),m/z237.0→m/z194.0(卡马西平,内标).结果 血浆中麦考酚酸的线性范围为0.1～10 μg·mL-1,方法 回收率为104.1%～106.6%,日内、日间精密度均小于7%.结论 本法简便、快速、灵敏、准确,已应用于肾移植后患者麦考酚酸酯的治疗药物监测.     

HPLC-/MS/MS法测定健康人血浆中普拉克索浓度

目的 建立高效液相串联质谱法测定人血浆中普拉克索浓度的方法.方法 在碱性条件下,用乙酸乙酯提取浓缩后,进样用LC-MS/MS,固定相为AQ-C18柱(4.6 mm× 150 mm,10 μm),流动相为乙腈-20 mmol·L-1醋酸铵水溶液=60:40,质谱条件为电喷雾离子源、正离子方式、多级离子反应监测,离子反应分别为m/z:212.2→152.9(普拉克索)和m/z 273.2→109.6(吡西卡尼).结果 普拉克索的血浆浓度在5 ～ 1000 pg·mL-1内线性关系良好,Y=1.33×103X+0.05(r=0.9979),定量下限可达5 pg·mL-1.结论 建立的检测方法准确、稳定,可满足血浆中普拉克索含量测定.     

五味子乙醇提取物的UPLC MS/MS分析

目的分析五味子乙醇提取物中的主要成分。方法UPLC MS/MS检测,通过与对照品的保留时间和质谱数据相比对,鉴定部分成分;通过质谱数据分析,并与相关文献比对,推测部分化合物结构。结果鉴定了五味子醇甲、五味子醇乙、五味子酯甲、五味子甲素、五味子乙素,推测另外17种成分,所有22种成分均为联苯环辛烯类木脂素。结论五味子乙醇提取物中主要存在联苯环辛烯类木脂素成分。     

Determination of oxaceprol in rat plasma by LC–MS/MS and its application in a pharmacokinetic study

A sensitive method for the quantification of oxaceprol in rat plasma using high-performance liquid chromatography–tandem mass spectrometry (LC–MS/MS) was developed. Sample pretreatment involved a simple protein precipitation by the addition of 60 μL of acetonitrile–methanol (1:2, v/v) to 20 μL plasma sample volume. Separation was achieved on a Dikma ODS-C18 (5 μm, 150 mm × 4.6 mm) reversed-phase column at 40 °C with acetonitrile/0.1% formic acid–4 mM ammonium acetate in water (35:65,v/v) at a flow rate of 0.6 mL/min. Detection was performed using an electrospray ionization (ESI) operating in negative ion multiple reaction monitoring (MRM) mode by monitoring the ion transitions from m/z 172 → 130 (oxaceprol) and m/z 153 → 109 (protocatechuic acid, internal standard). The calibration curve of oxaceprol in plasma showed good linearity over the concentration range of 1.25–800 ng/mL. The limit of detection and limit of quantification were 0.400 ng/mL and 1.25 ng/mL, respectively. Intra- and inter-day precisions in all samples were within 15%. There was no matrix effect. The validated method was successfully applied to a preclinical pharmacokinetic study of oxaceprol in rats. After oral administration of 20 mg/kg oxaceprol to rats, the main pharmacokinetic parameters T_max, C_max, T_1/2, V_z/F and AUC_0–t were 1.4 h, 1.2 μg/mL, 2.3 h, 19.7 L/kg and 3.4 mg h/L, respectively.     

Determination of cepharanthine in rat plasma by LC–MS/MS and its application to a pharmacokinetic study

Context: Cepharanthine (CPA) has been reported to possess a wide range of pharmacological activities.

Objective: This study investigates the pharmacokinetic characteristics after oral or intravenous administration of CPA by using a sensitive and rapid LC–MS/MS method.

Materials and methods: A sensitive and rapid LC–MS/MS method was developed for the determination of CPA in Sprague–Dawley rat plasma. Twelve rats were equally randomized into two groups, including the intravenous group (1?mg/kg) and the oral group (10?mg/kg). Blood samples (250?μL) were collected at designated time points and determined using this method. The pharmacokinetic parameters were calculated.

Results: The calibration curve was linear within the range of 0.1–200?ng/mL (r?=?0.999) with the lower limit of quantification at 0.1?ng/mL. After 1?mg/kg intravenous injection, the concentration of CPA reached a maximum of 153.17?±?16.18?ng/mL and the t_1/2 was 6.76?±?1.21?h. After oral administration of 10?mg/kg of CPA, CPA was not readily absorbed and reached C_max 46.89?±?5.25?ng/mL at approximately 2.67?h. The t_1/2 was 11.02?±?1.32?h. The absolute bioavailability of CPA by oral route was 5.65?±?0.35%, and the bioavailability was poor.

Discussion and conclusions: The results indicate that the bioavailability of CPA was poor in rats, and further research should be conducted to investigate the reason for its poor bioavailability and address this problem.     

Biopharmaceutical and pharmacokinetic characterization of matrine as determined by a sensitive and robust UPLC–MS/MS method

The purpose of this research was to develop a sensitive and reproducible UPLC–MS/MS method to analyze matrine, an anticancer compound, and to use it to investigate its biopharmaceutical and pharmacokinetic behaviors in rats. A sensitive and fast UPLC–MS/MS method was successfully applied to determine matrine in rat plasma, intestinal perfusate, bile, microsomes, and cell incubation media. The absolute oral bioavailability of matrine is 17.1 ± 5.4% at a dose of 2 mg/kg matrine. Matrine at 10 μM was shown to have good permeability (42.5 × 10⁻⁶ cm/s) across the Caco-2 cell monolayer, and the ratio of P_A–B to P_B–A was approximately equal to 1 at two different concentrations (1 and 10 μM). Perfusion study showed that matrine displayed significant differences (P < 0.05) in permeability at different intestinal regions. The rank order of permeability was ileum (highest, P_w = 6.18), followed by colon (P_w = 2.07), duodenum (P_w = 0.61) and jejunum (P_w = 0.52). Rat liver microsome studies showed that CYP and UGTs were not involved in matrine metabolism. In conclusion, a sensitive and reliable method capable of measuring matrine in a variety of matrixes was developed and successfully used to determine absolute oral bioavailability of matrine in rats, transport across Caco-2 cell monolayers, absorption in rat intestine, and metabolism in rat liver microsomes.     

大鼠血浆中积雪甙浓度的HPLC/MS/MS测定

建立了HPLC／MS／MS测定大鼠血浆中的积雪甙。以柴胡皂甙D为内标，采用XTerra C18柱，流动相为O．1％乙酸和含O．1％乙酸的乙腈，梯度洗脱。质谱条件为电喷雾离子源，检测方式为多反应检测，定量分析离子为m／z981．5→493（积雪甙）和803→331（柴胡皂甙D），血浆样品采用固相萃取处理。检测限为0．5ng／ml。     

LC/MS/MS法测定人血浆中头孢克肟含量

目的 建立人血浆中头孢克肟的LC/MS/MS法.方法 血浆样品经蛋白沉淀提取,采用C8色谱柱分析,以乙腈:水:甲酸(40:60:0.5,v/v/v)为流动相,三重四级杆质谱检测器,正离子多反应监测模式(MRM),监测离子分别为:m/z 454.3→m/z 285.2(头孢克肟),m/z 282.2→m/z 212.2(...     

Development and validation of a LC–MS/MS method for determination of bivalirudin in human plasma: Application to a clinical pharmacokinetic study

A simple, sensitive and rapid LC–MS/MS method has been developed and validated for the identification and quantification of bivalirudin in human plasma using nafarelin as the internal standard. Following protein precipitation with methanol, the analytes were separated on a C₁₈ column interfaced with a triple-quadrupole tandem mass spectrometer using positive electrospray ionization. Quantification of bivalirudin was conducted by multiple reaction monitoring (MRM) of the transitions of m/z 1091.4 → (356.4 + 227.4) for bivalirudin and m/z 662.4 → 328.5 for IS. The lower limit of quantification was 1.25 ng/ml, and the assay exhibited a linear range of 1.25–500 ng/ml. The developed assay method was successfully applied to a pharmacokinetic (PK) study in healthy volunteers after intravenous administration of bivalirudin.     

Development of a simultaneous LC–MS/MS method to predict in vivo drug–drug interaction in mice

Cocktail substrates are useful in investigating drug–drug interactions (DDI) that can rapidly identify the cytochrome P450 (CYP) isoforms that interact with test drugs. In this study, we developed and validated five probe drugs for CYP1A, CYP2B, CYP2C, CYP2D, and CYP3A using LC–MS/MS to determine CYP activities in mice. The five probe substrates were caffeine (2 mg/kg), bupropion (30 mg/kg), omeprazole (4 mg/kg), dextromethorphan (40 mg/kg), and midazolam (2 mg/kg) for CYP1A, CYP2B, CYP2C, CYP2D, and CYP3A, respectively. The cocktail substrates were orally administered to male 5-week-old ICR mice over 0–240 min. The analytical method was validated; it showed high selectivity, linearity, and acceptable accuracy. We confirmed the lack of interaction of this cocktail in the control state (no effect of CYP inducer or inhibitor) and suggested AUC_ratio (metabolite/substrate) as a unit to evaluate DDI in vivo. In addition, the cocktail assay was applied for the determination of pharmacokinetic parameters against phenobarbital as a selective CYP2B inducer and ketoconazole as a strong CYP3A inhibitor. The concentration of cocktail substrates and the LC–MS/MS method were optimized. In conclusion, we developed a simultaneous and comprehensive analysis system for predicting potential DDI in mice.     

LC/MS/MS的多反应监测方法定量测定灯盏乙素

目的：建立一种可靠的灯盏乙素定量分析方法。方法：用三级四极串联质谱(MS/MS)作为HPLC的检测器,其中MS/MS使用了多反应监测(MRM)扫描方式。选择母→子离子对m/z -461→m/z -285作为MRM监测的离子对;HPLC流动相为100％甲醇,流速0.9 mL.min^-1,色谱柱Beckman ODS-1。以测定短葶飞蓬提取物的灯盏乙素含量为例,对此方法进行了应用。结果：灯盏乙素在短葶飞蓬提取物中含量为6.98%。方法线性范围20～160 ng.mL^-1 (γ=0.999);加入灯盏乙素标准品20,60和160 ng的加样回收率分别为：96.5%,97.4%和97.3%。检测限为1 ng,每个样品的分析时间为4 min。结论：此法灵敏、快速、准确,可应用于灯盏乙素的各种药剂、药代的研究。     

HPLC/MS/MS测定铁皮石斛制剂中12种农药残留量

目的建立同时测定铁皮石斛制剂中12种农药残留量的分析方法。方法样品用乙腈超声提取,经过石墨化碳/氨基固相萃取柱净化,用高效液相色谱 质谱串联法测定,采用内标法定量。结果方法回收率72.1%～119.5%,RSD均＜15%。各农药检测限均＜0.001 mg&#8226;kg－1。结论该方法简单,快速,灵敏,结果准确,重复性好,可用于铁皮石斛制剂12种农药残留量的测定。     

LC/MS/MS法测定人血浆中伊曲康唑的浓度

目的 建立高效液相色谱-质谱联用(LC/MS/MS)法测定人血浆中伊曲康唑浓度的方法.方法 在血浆样品中加入氟康唑作内标,用甲醇/叔丁基甲醚(1∶5,V/V)提取.采用Waters Symmetry C18(3.9mm×100mm,5μm)色谱柱;柱温25℃;流动相为甲醇-水(含10mmol/L甲酸铵)(85∶15,V/V);流速为0.5mL/min.三重四极杆质谱采用正离子模式;电喷雾离子源(ESI);离子源温度260℃,离子源电离电压为3800V,雾化气流速480L/h.以多反应监测(MRM)方式进行检测;检测离子(母离子/子离子)伊曲康唑为705.6/393.2,氟康唑(内标)为307.2/220.1.结果 伊曲康唑在1～600ng/mL线性范围内呈良好线性(r=0.9996).日内、日间精密度在15%以内,绝对回收率大于85%,相对回收率为91.2%-101.5%.结论 本方法灵敏、准确,可以用来进行伊曲康唑的血药浓度监测、人体药动学和生物等效性研究.