Liquid chromatographic-tandem mass spectrometric method for the simultaneous quantitation of telmisartan and hydrochlorothiazide in human plasma

A rapid and sensitive method using liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been developed for the simultaneous determination of telmisartan and hydrochlorothiazide in human plasma. Sample preparation involved liquid-liquid extraction with diethyl ether-dichloromethane (60:40, v/v). The analytes and internal standard, probenecid, were separated on a Venusil XBP-C(8) column using gradient elution with acetonitrile-10 mM ammonium acetate-formic acid at a flow rate of 1.2 mL/min. Detection was by electrospray negative ionization mass spectrometry using multiple reaction monitoring of the transitions at m/z 513.0-->469.4 for telmisartan, m/z 295.9-->268.9 for hydrochlorothiazide and m/z 283.9-->239.9 for probenecid. For both analytes, the method was linear in the range 1.00-600 ng/mL with intra- and inter-day precision (as relative standard deviation) 相似文献   

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。     

高灵敏度LC-MS/MS法测定犬血浆中的坦洛新

犬口服盐酸坦洛新控释片后血浆药物浓度C_max小于10 ng·mL^-1，需建立测定犬血浆中坦洛新的高灵敏度液相色谱-串联质谱法(LC-MS/MS)。血浆样品加入内标苯海拉明，用正己烷-二氯甲烷(2∶1)萃取后，反相C₁₈色谱柱分离，以甲醇-乙腈-甲酸铵(30∶40∶30，v/v/v)为流动相，流速为0.4 mL·min^-1。选用大气压化学离子化源(APCI)三重四极杆串联质谱仪，以选择反应监测方式进行检测，用于定量分析的离子反应分别为m/z 409→228(坦洛新)和m/z 256→167(苯海拉明)。坦洛新线性范围为0.02～50 ng·mL^-1，定量下限为0.02 ng·mL^-1。批内、批间精密度(RSD)均小于9.72%，准确度(RE)在-2.61%～8.82%。本方法灵敏度高，专属性强，用于犬口服盐酸坦洛新控释片后的药代动力学研究。     

高灵敏度LC/MS/MS法同时测定人血浆中麻黄碱和氯苯那敏

麻黄碱是存在于草麻黄和木贼麻黄等植物中的生物碱,属拟肾上腺素类药物,包括互为差向异构体的麻黄碱和伪麻黄碱两种活性不同的成分;氯苯那敏为丙胺类组胺H1-受体拮抗剂,作用较强,用量少,中枢抑制作用小,为常用抗过敏药,临床上可用于缓解各种感冒症状,与麻黄碱联合应用,用于缓解支气管哮喘与慢性喘息性支气管炎所致支气管痉挛.     

Determination and pharmacokinetics of danshensu in rat plasma after oral administration of danshen extract using liquid chromatography/tandem mass spectrometry.

A liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was developed and validated for the determination and pharmacokinetics of danshensu in rat plasma samples using ferulic acid as internal standard (IS). The plasma samples were treated by liquid-liquid extraction, and the analyses were determined using electrospray negative ionization mass spectrometry in selected reaction monitoring (SRM) mode. The signal intensity of the m/z 196.8 --> 134.8 transition of danshensu was found to relate linearly to danshensu concentrations in the plasma from 5-500 ng/mL. The lower limit of quantification (LLOQ) as determined by the LC/MS/MS method amounted to 5 ng/mL. The intra- and inter-day precision was below 10.82%, and the accuracy was between -3.51% and +11.92%. The validated LC/MS/MS method was applied to a pharmacokinetic study in which danshen extract (containing 40 mg/g danshensu) was administered orally to rats at a single dose of 200 mg/kg in 2% water.     

Development of LC/MS/MS assay for the determination of 5-ethyl-2-{5-[4-(2-hydroxyethyl)piperazine-1-sulfonyl]-2-propoxyphenyl}-7-propyl-3,5-dihydropyrrolo[3,2-d]pyrimidin-4-one (SK3530) in human plasma: application to a clinical pharmacokinetic study

5-Ethyl-2-{5-[4-(2-hydroxyethyl)piperazine-1-sulfonyl]-2-propoxyphenyl}-7-propyl-3,5-dihydropyrrolo[3,2-d]pyrimidin-4-one (SK3530) is a new phosphodiesterase type-5 inhibitor currently undergoing a Phase III investigation for the treatment of male erectile dysfunction. This study first describes a rapid and sensitive LC/MS/MS assay method for the quantification of SK3530 and its major metabolite, SK3541, in human plasma. The assay was validated to demonstrate the specificity, linearity, recovery, lower limit of quantification (LLOQ), accuracy, and precision. The multiple reaction monitoring was based on the transition of m/z=532.5-->99.1 for SK3530, 488.6-->295.5 for SK3541, and 520.3-->99.1 for SK3304 (internal standard). The assay utilized a single liquid-liquid extraction and isocratic elution, and the LLOQ was 1 ng/ml using 0.2 ml human plasma. The assay was linear over a range from 1 to 1000 ng/ml for both SK3530 and SK3541, with correlation coefficients >0.9999. The mean intra- and inter-day assay accuracy ranged from 94.7 to 101.6% and 96.8 to 101.1% for SK3530 and 92.6-105.7% and 97.4-107.8% for SK3541, respectively. The mean intra- and inter-day precision was between 7.2-12.1% and 5.7-7.4% for SK3530 and 4.6-13.2% and 5.0-14.1% for SK3541, respectively. The developed assay was applied to a clinical pharmacokinetic study after oral administration of SK3530 in healthy male volunteers (dose 100 mg).     

Determination of pinostrobin in rat plasma by LC-MS/MS: application to pharmacokinetics

A rapid and sensitive method for the determination of pinostrobin in rat plasma was developed using liquid chromatography tandem mass spectrometry (LC-MS/MS) for the first time. Isoliquiritigenin was used as an internal standard in rat plasma. Chromatographic separation was performed on an HiQ Sil C₁₈ column with isocratic elution at a flow rate of 1 mL/min. The mobile phase consisted of water and methanol (9:91, v/v) containing 0.1% formic acid. The quantification limit was 10 ng/mL within a linear range of 10-1000 ng/mL (R = 0.9984). The intra- and inter-day assay precision ranged from 3.8-5.3% to 3.2-5.2%, respectively, and the intra- and inter-day assay accuracy was between 93.2-95.1% and 95.5-104.3%, respectively. Our results indicated that the LC-MS/MS method is effective for pharmacokinetic study of pinostrobin in rat plasma.     

液相色谱-串联质谱法测定犬血浆中布地奈德

建立液相色谱-串联质谱法测定犬血浆中布地奈德。血浆样品碱化后，经乙酸乙酯液-液萃取，以乙腈-5 mmol·L^-1醋酸铵(60∶40，v/v)为流动相，Capcell Pak C₁₈ MG柱分离；采用电喷雾电离源，以多反应监测(MRM)方式进行负离子检测，用于定量分析的离子反应分别为m/z 489→m/z 357(布地奈德)和m/z 493→m/z 413(内标，曲安奈德)。测定血浆中布地奈德方法的线性范围为25.0～2 000 pg·mL^-1，定量下限为25.0 pg·mL^-1，日内、日间精密度(RSD)均小于15%，准确度(RE)在-8.1%～-1.7%。应用本法研究6只比格犬单次和多次给予布地奈德缓释胶囊9 mg后的药代动力学结果显示：单次给药后T_max为(3.5±3.3) h，C_max为(786±498) pg·mL^-1；多次给药后C_max为(2 142±1 515) pg·mL^-1。该法选择性强、灵敏度高、操作简便，适用于布地奈德缓释制剂的药代动力学研究。     

Quantification of tulobuterol,a selective β2 adrenergic agonist,in human plasma by liquid chromatography-tandem quadrupole mass spectrometry

A simple and highly sensitive method coupled with liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) was developed and validated for the determination of tulobuterol in human plasma. Sample was preparated by liquid-liquid extraction with i-propanol–n-hexane (5:95, v/v). Tulobuterol and tulobuterol-d9 (internal standard, IS) were separatedon a 300 Extend C₁₈ column(4.6 mm×150 mm, 5 µm), using 0.1%formic acid (A)–acetonitrile (B) (30:70, v/v) as the mobile phase at the flow rate of 1.0 mL/min with an approximately 1:1 split entering the mass spectrometer. Detection was performed by positive electrospray ionization mass spectrometry multiple reaction monitoring of the precursor-to-product ion transition of tulobuterol at m/z 228.1→m/z 154.0 and tulobuterol-d9 atm/z 237.2→m/z 154.0. The assay was linear over the range 0.01–5.0 ng/mLwith a lower limit of quantitation of 0.01 ng/mL. The intra- and inter-day precisions were 3.7% and 11.1%, respectively. Recoverywas approximately 66%, and matrix effects were minimal. This method also showed satisfactory sensitivity, specificity, and carryover. The method was successfully applied to a pharmacokinetic study of tulobuterol in healthy volunteers who were given the tulobuterol patch containing 2 mg tulobuterol.     

液相色谱-串联质谱法测定人血浆中的利培酮

利培酮为苯并异噁唑类化合物,通过阻断5-HT2受体和多巴胺D2受体发挥抗精神病作用.同其他抗精神病药物相比,利培酮所引起的椎体外系副作用更少,药效更为明显 .     

Simultaneous determination of amoxicillin and ambroxol in human plasma by LC-MS/MS: validation and application to pharmacokinetic study

A rapid, simple and sensitive LC-MS/MS method was developed for simultaneous determination of amoxicillin and ambroxol in human plasma using clenbuterol as internal standard (IS). The plasma samples were subjected to a simple protein precipitation with methanol. Separation was achieved on a Lichrospher C(18) column (150 mm x 4.6mm ID, dp 5 microm) using methanol (containing 0.2% of formic acid) and water (containing 0.2% of formic acid) as a mobile phase by gradient elution at a flow rate of 1.0 mL/min. Detection was performed using electrospray ionization in positive ion multiple reaction monitoring (MRM) mode by monitoring the ion transitions from m/z 365.9-->348.9 (amoxicillin), m/z 378.9-->263.6 (ambroxol) and m/z 277.0-->203.0 (IS). Calibration curves were linear in the concentration range of 5-20,000 ng/mL for amoxicillin, and 1-200 ng/mL for ambroxol, with the intra- and inter-run precisions of <9% and the accuracies of 100+/-7%. The method has been validated and applied to pharmacokinetic studies of compound amoxicillin and ambroxol hydrochloride tablets in healthy Chinese volunteers.     

Development and validation of a liquid chromatography with tandem mass spectrometry (LC-MS/MS) method for the determination of sunitinib in rabbit plasma

A liquid chromatography with tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the measurement of sunitinib in rabbit plasma. After protein precipitation with acetonitrile, samples were analyzed on a Zorbax Extend-C₁₈ column (150 mm×4.6 mm, 5μm). The mobile phase consisted of a mixture of acetonitrile and deionized water (containing 0.05% formic acid)at a ratio of 27:73 (v/v), and the flow rate was set at 0.8 mL/min.The column temperature was maintained at 30 ^oC. The LC eluate was detected by an electrospray ionization (ESI) source operated in the positive ion mode, and quantification was conducted using MRM of the transitions m/z 399.24→283.01 and m/z 415.19→178.00 for sunitinib and internal standard (IS, diltiazem hydrochloride), respectively. The calibration curve was linear in the range of 2–600 ng/mL. The lower limit of quantification was 2 ng/mL. The method also exhibited satisfactory results in terms of sensitivity, specificity, accuracy (with relative error ranging from –4.0% to 1.1%), precision (with intra- and inter-day relative standard deviations ranging from 2.8% to 9.5%),matrix effect, recovery as well as stability. Taken together, our newly developed method was reliable to monitor sunitinib concentrations in rabbit plasma.     

Determination of paroxetine in plasma by liquid chromatography coupled to tandem mass spectrometry for pharmacokinetic and bioequivalence studies

A rapid and validated liquid chromatography coupled to tandem mass spectrometric method (LC-MS-MS) has been developed and applied to pharmacokinetic and bioequivalence studies in 24 healthy male Korean volunteers. The procedure involves a liquid-liquid extraction of paroxetine (CAS 61869-08-7) and fluoxetine (internal standard, CAS 54910-89-3) with ether/methyl chloride (7:3, v/v) and separated by LC equipped with C18 column using acetonitrile: 5 mmol/L ammonium formate (4:3, v/v) as mobile phase. Detection is carried out on an API 2000 MS system by multiple reactions monitoring mode. The ionization was optimized using ESI(+) and selectivity was achieved by MS-MS analysis, mlz 330.0-->192.0 and m/ z 310-->148 for paroxetine and fluoxetine, respectively. The method has a total run time of 1.5 min and was linear over a working range of 0.05-20 ng/mL and the lower limit of quantification was 0.05 ng/ mL. No endogenous compounds were found to interfere with the analysis. The inter-day and intra-day accuracy was in the ranges of 102.69-107.79% and 102.07-109.57%, respectively and precision of inter-day and intra-day expressed as relative standard deviation were 1.86-9.99% and 1.52-6.28%, respectively. The validation of this method on linearity, specificity, accuracy, precision as well as applicability to pharmacokinetic and bioequivalence studies by analysis of blood samples taken up to 72 h after oral administration of 20 mg of paroxetine in 24 healthy volunteers were found to be good performance.     

Liquid chromatographic/mass spectrometry assay of triptolide in dog plasma and its application to pharmacokinetic study

A rapid and sensitive method for the determination of triptolide in dog plasma was developed and validated, using high-performance liquid chromatography/atmospheric pressure chemical ionization mass spectrometry (LC/APCI/MS). Sample preparation consisted of liquid-liquid extraction with ethyl acetate from dog plasma. The analytes and internal standard prednisolone were well separated on a Zorbax Extend-C18 analytical column. Detection was performed on a triple quadrupole mass spectrometer using selected-ion monitoring (SIM) mode on the deprotonated ions [M-H]- at m/z 359. Calibration curves were linear over the concentration range of 0.5-200 ng/mL of triptolide with the intra- and inter-day precision (the relative standard deviation values) were being less than 7%. Triptolide was stable under different conditions. The intra-day and inter-day accuracy were 99.3-105.2% and 101.3-107.0%, respectively. The lower limit of quantification was 0.5 ng/mL. The method was successfully applied to a pharmacokinetic study after an intragastric administration (i.g.) of triptolide to dogs with a dose of 0.05 mg/kg. The results confirm that the assay is suitable for the pharmacokinetic study of triptolide.     

Rapid and sensitive HPLC-MS/MS method for quantitative determination of isochlorogenic acid B in rat plasma and its application in pharmacokinetic study

Asensitive LC-ESI-MS/MS method for determination of isochlorogenic acid B in rat plasma was developed and validated in the present study. Plasma samples were prepared by a simple protein precipitation with methanol containing resveratrol as internal standard (IS). The chromatographic separation was performed on a Zorbax SB-C₁₈ column (3.5 μm, 2.1 mm×100 mm, Agilent, USA) at a flow rate of 0.2 mL/min using methanol/water containing 0.1% formic acid (v/v) as mobile phase. The detectionwas performed on a triple quadrupole tandem mass spectrometer equipped with Electronic Spray Ion by selected reaction monitoring (SRM) of the transitions at m/z 515.3→352.9 for isochlorogenic acid B and m/z 227.1→143.1 for IS, respectively. The calibration curve of the method was linear over the range of 5–2500 ng/mL (r² = 0.9982). The intra- and inter-day precisions (R.S.D.%) were less than 12.46%, and the accuracy (R.E.%) was within ±5.80%. Isochlorogenic acid B was sufficiently stable under all relevant analytical conditions. The validated method was successfully applied to the plasma pharmacokinetic studies of isochlorogenic acid B in rats. It was found that isochlorogenic acid B had non-linear pharmacokinetic characteristics in rats within the dosage ranges from 5 to 20 mg/kg.     

Liquid chromatography/tandem mass spectrometry for the determination of carbamazepine and its main metabolite in rat plasma utilizing an automated blood sampling system

A liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for the simultaneous determination of carbamazepine and its main metabolite carbamazepine 10,11-epoxide in rat plasma is described. The method consists of a liquid-liquid extraction procedure and electrospray LC/MS/MS analysis. The chromatographic separation was achieved within 5 min using a C(8) (150 mm x 2.1mm) 5 microm column with a mobile phase composed of water/acetonitrile/acetic acid (69.5:30:0.5, v/v/v) at a flow rate of 0.4 ml/min. D(10)-carbamazepine is used as the internal standard for all compounds. Analytes were determined by electrospray ionization tandem mass spectrometry in the positive ion mode using selected reaction monitoring (SRM). Carbamazepine was monitored by scanning m/z 237-->194, carbamazepine 10,11-epoxide by m/z 253-->210 and d(10)-carbamazepine by m/z 247-->204. The lower limit of quantitation (LLOQ) is 5 ng/ml for each analyte, based on 0.1 ml aliquots of rat plasma. The extraction recovery of analytes from rat plasma was over 87%. Intra-day and inter-day assay coefficients of variations were in the range of 2.6-9.5 and 4.0-9.6%, respectively. Linearity is observed over the range of 5-2000 ng/ml. This method was used for pharmacokinetic studies of carbamazepine and carbamazepine 10,11-epoxide in response to two different blood sampling techniques (i.e., manual sampling versus automated sampling) in the rat. Several differences between the two sampling techniques suggest that the method of blood collection needs to be considered in the evaluation of pharmacokinetic data.     

UPLC-MS/MS法同时测定人血浆中黄芩苷和绿原酸

建立UPLC-MS/MS法同时测定人血浆中黄芩苷和绿原酸的浓度，研究注射用银黄在健康人体的药代动力学。色谱柱为BEH C₁₈(50 mm×2.1 mm ID，1.7 μm)；流动相：A(水，0.1%甲酸)，B(甲醇，0.1%甲酸)，梯度洗脱；流速：0.35 mL·min^-1。电喷雾离子源，多反应监测。黄芩苷：［M+H］⁺，m/z 447→271；绿原酸：［M-H］^-，m/z 353→191；山柰素：［M+H］⁺，m/z 287→287。结果表明，黄芩苷和绿原酸血药浓度的线性范围分别为9.6～1 540和7.5～1 200 ng·mL^-1，日内、日间精密度均小于10.2%。志愿者静脉滴注注射用银黄后，黄芩苷和绿原酸的药时曲线分别符合二房室和三房室模型。该法简便、灵敏、特异，适用于血浆中黄芩苷和绿原酸浓度的测定。     

Simultaneous determination of GFA and its active metabolites in human plasma by liquid chromatography electrospray ionization mass spectrometry and its application to pharmacokinetic studies

A sensitive and rapid liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS) method has been developed and validated for simultaneous quantification of guanfu base A (GFA) and its metabolites guanfu base I (GFI) and guanfu alcohol-amine (AA) in human plasma with phenoprolamine hydrochloride (DDPH) as the internal standard. The analytes were extracted from human plasma by using liquid-liquid extraction with ethyl acetate and the LC separation was performed on a Diamonsil C(18) analytical column (150 mm x 2.1 mm i.d., 5 microm). The MS acquisition was performed in selected ion monitoring (SIM) mode of positive ions. Analysis was carried out in SIM mode at m/z 430.25 for GFA [M+H](+), m/z 388.25 for GFI [M+H](+), m/z 346.25 for AA [M+H](+) and m/z 344.20 for the IS DDPH [M+H](+). The calibration curves were linear over the range of 50-5000 ng/mL for GFA and 5-1000 ng/mL for GFI and AA, with coefficients of correlation above 0.999. The lower limit of quantification for GFA was 1 ng/mL, while for GFI and AA were both 5 ng/mL. The intra- and inter-day precisions (CV) of analysis were within 9%, and the accuracy ranged from 91% to 108%. The overall recoveries for GFA, GFI and AA were about 94.2%, 87.8% and 80.6%, respectively. The total LC-MS run-time was only 5.5 min. This quantitation method was successfully applied to the simultaneous determination of GFA and its metabolites in human plasma for the metabolic study and pharmacokinetic evaluation.     

Pharmacokinetic characterization of a novel α7 nicotinic acetylcholine receptor (nAChR) positive allosteric modulator LD486 in rat plasma using a validated LC-MS/MS assay

The deficiency of neuronal α7-nicotinic acetylcholine receptor (α7 nAChR) channel is implicated in cognition deficit and neuropsychiatric disorders. Chemical activation of α7 nAChR improves learning, memory, and sensory gating in animal models. To identify novel α7 nAChR activators, we recently identified a lead compound LD486 that as a positive allosteric modulator (PAM) selectively activates α7 nAChR. In this study we developed a simple, reliable and efficient assay of high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) and analyzed the pharmacokinetics of this novel LD486 in rat plasma. Separation of compound LD486 from plasma was achieved using a reversed-phase C₁₈ column with a mobile phase of 0.1% formic acid in H₂O (80:20, v:v), using compound A1223 as an internal standard (IS) with a flow rate of 0.5 mL/min. The quantitative analysis was performed using multiple reaction monitoring (MRM) at the specific ion transition of m/z 419.0 [M+H]⁺→m/z 169.0 for LD486 and m/z 400.0 [M+H]⁺→m/z 129.9 for A1223 in the positive ion mode with electrospray ionization (ESI) source. This validated LC-MS/MS method shows good linearity over the range 4–4000 ng/mL with the lowest limit of quantitation (LLOQ) at 4 ng/mL as well as satisfied intra- and inter-day precision, accuracy, extraction recovery and matrix effect.The stability testing indicates that LD486 in rat blood is stable under three freeze-thaw cycles, in room temperature at 22 ^oC for 2 h and 12 h, and for 2 weeks at −20 ^oC. This developed method was successfully applied to the pharmacokinetic analysis of intravenous (1 mg/kg) and oral (3 mg/kg and 30 mg/kg) administration of LD486 in SD rats.     

Development and full validation of a sensitive quantitative assay for the determination of clemastine in human plasma by liquid chromatography-tandem mass spectrometry

A sensitive high-performance liquid chromatography-tandem mass spectrometry (LC/MS/MS) method was developed and validated for the determination of clemastine in human plasma. After having been extracted from plasma samples by ethyl acetate, clemastine and internal standard, diphenhydramine, were separated on a C(18) column. Detection was performed on Thermo Finnigan TSQ Quantum triple quadrupole mass spectrometer by selected reaction monitoring (SRM) mode via electrospray ionization (ESI) source. The method was linear in the concentration range of 5.0-1000.0 pg/ml for clemastine. The intra- and inter-day precisions were within 13.4% and the deviations were between -1.1% and 5.6%. The fully validated LC/ESI-MS/MS method has been successfully applied to the preliminary pharmacokinetic study in healthy male Chinese volunteers.