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.     

Quantification of voriconazole in human plasma by high-performance liquid chromatography-electrospray ionization mass spectrometry: application to a bioequivalence study

A sensitive and specific liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) method was developed and validated for the identification and quantification of voriconazole (VRC, CAS 137234-62-9) in human plasma. Following liquid-liquid extraction, VRC and loratadine (internal standard, CAS 79794-75-5) were separated using a mobile phase comprised of methanol: water (0.1% formic acid) = 75:25 v/v on a Shimadzu Shim-pack VP-ODS C18 (150 x 2.0 mm ID, 5 microm) column and analyzed by electrospray ionization mass spectrometry. The chromatographic separation was achieved in less than 6 min. The standard curves were linear (r = 0.9994) over the concentration range of 2-2000 ng/mL for VRC and had good accuracy and precision. Both intra- and inter-batch standard deviations were less than 15%. The method was successfully applied to study the comparative bioavailability of VRC tablets test vs. reference in healthy Chinese volunteers through the statistical comparison of pharmacokinetic parameters obtained with the two formulations.     

LC–MS/MS method for the quantitation of decitabine and venetoclax in rat plasma after SPE: Application to pharmacokinetic study

This study developed a novel, sensitive and selective LC-MS/MS method for the concurrent determination of DCB and VTX in rat plasma using encorafenib as internal standard (IS). To identify DCB, VTX, and IS, the positive multiple reaction monitoring (MRM) mode was used. Chromatographic separation was carried out using a reversed-phase Agilent Eclipse plus C18 column (100 mm × 2.1 mm, 3.5 µm) and an isocratic mobile phase made up of water with 0.1% formic acid and acetonitrile (50:50, v/v, pH 3.2) at a flow rate of 0.30 mL/min for 3.0 min. Prior to analysis, the DCB and VTX with the IS were extracted from plasma using the solid-phase extraction (SPE) method. High recovery rates for DCB, VTX and IS were achieved using the C18 cartridge without interference from plasma endogenous. The developed method was validated as per the FDA guidelines over a linear concentration range in rat plasma from 5–3000 and 5–1000 ng/mL for DCB and VTX, respectively with r² ≥ 0.998. For both drugs, the lower limits of detection (LLOD) were 2.0 ng/mL. After the HLOQ sample was injected, less than 20% of the LLOQ of DCB, VTX, and less than 5% of the IS carry-over in the blank sample was attained. The overall recoveries of DCB and VTX from rat plasma were in the range of 90.68–97.56%, and the mean RSD of accuracy and precision results was ≤6.84%. For the first time, the newly developed approach was effectively used in a pharmacokinetic study on the simultaneous oral administration of DCB and VTX in rats that received 15.0 mg/kg of DCB and 100.0 mg/kg of VTX.     

Development and validation of a sensitive LC/MS-MS method for the determination of letrozole in nude mice plasma and its application to a pharmacokinetic study

A sensitive, rapid and simple liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and validated for the determination of letrozole (LTZ) in nude mouse plasma in the current study, which was successfully applied to a pharmacokinetic study. Using anastrozole as internal standard (IS), plasma samples went through a one-step protein precipitation with acetonitrile before determination. The analyte and IS were analyzed on a reversed-phase ZORBAX-SB-C₁₈column (4.6 mm×250 mm, 5 μm) with an isocratic mobile phase consisting of acetonitrile and water containing 0.1% formic acid (v/v) at a flow rate of 1.0 mL/min. The analyte and IS were detected by a triple-quadrupole tandem mass spectrometer, and electrospray and multiple reaction monitoring (MRM) were employed to select LTZ at m/z 286.4/217.1 and IS at m/z 294.1/225.3 simultaneously in the positive ion mode. The calibration curve showed good linearity ranging from 0.8–2000.0 ng/mL (r>0.99). The intra-day and inter-day precisions of LTZ were 4.0%–8.4%, with an accuracy of 98.6%–104.9%. Using this method, we successfully characterized the pharmacokinetics (PK) of LTZ by a one-compartment model with first-order absorption in female BALB/c nude mice.     

Quantification of flupirtine and its active metabolite D-13223 in human plasma by LC-MS/MS: application to a clinical trial of flupirtine maleate capsules in healthy male Chinese volunteers

In the present study, we developed a simple, sensitive, precise, and accurate liquid chromatography-tandem mass spectrometric (LC-MS/MS) method and validated such approach for simultaneous determination of flupirtine and its active metabolite D-13223 in human plasma. The flupirtine, D-13223, and stable isotope internal standard (IS) were extracted from plasma samples by liquid-liquid extraction and chromatographed on a C18 column with a mobile phase consisting of acetonitrile–water–ammonia (55:45:0.1, v/v/v) at a flow rate of 0.25 mL/min. Detection was performed on a triple quadrupole tandem mass spectrometer with an electrospray ionization source (ESI) by multiple reaction monitoring (MRM) in positive ion mode. The linear calibration curves were obtained within the concentration range of 10.00–2000.00 ng/mL for flupirtine and 2.00–400.00 ng/mL for D-13223. The intra- and inter-run RSD, calculated from quality control (QC) samples, was less than 9.26% for flupirtine and D-13223. The accuracy was –5.80%–3.31% for flupirtine and D-13223. The extraction recoveries of flupirtine, D-13223, and their IS were all between 88.3%–97.2%. The method was successfully applied to investigate the pharmacokinetic profiles of flupirtine and its active metabolite D-13223 in human plasma following peroral administration of 100 mg flupirtine maleate capsules in healthy male Chinese volunteers.     

Development and validation of a LC-MS method with electrospray ionization for the determination of the imidazole H3 antagonist ROS203 in rat plasma

A rapid, simple and sensitive liquid chromatography-mass spectrometry (LC-MS) method was developed and validated for the determination of the imidazole H(3) antagonist ROS203 in rat plasma, using the superior homologue ROS287 as internal standard. Analyses were performed on an Agilent 1100 Series HPLC system employing a Supelco Ascentis C(18) column and isocratic elution with acetonitrile-10mM ammonium acetate buffer pH 4.0 (30:70, v/v) at a flow rate of 0.25 mL/min. An Applied Biosystems/MDS Sciex 150-EX single quadrupole mass spectrometer, equipped with an electrospray ionization interface was employed, operating in the positive ion mode. Plasma samples were deproteinized with acetonitrile (1:2), evaporated under nitrogen stream, reconstituted in the mobile phase and 5 microL were injected into the system. The retention times of ROS203 and IS were 2.20 and 2.90 min, respectively. Calibration curves in spiked plasma were linear over the concentration range of 2610-2.61 ng/mL with determination coefficients >0.99. The lower limit of quantification (LLOQ) was 2.61 ng/mL. The accuracy of the method was within 15%. Intra- and inter-day relative standard deviations were less or equal to 9.50% or 7.19%, respectively. The applicability of the LC-MS method was tested employing plasma samples obtained after i.p. administration of ROS203 to female Wistar rats to support a behavioral in vivo study. The specificity of the method was confirmed by the absence of interferences from endogenous substances. The reported method can provide the necessary sensitivity, linearity, precision, accuracy and specificity to allow the determination of ROS203 in rat plasma samples to support further pharmacokinetic assays.     

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.     

Development and validation of a liquid chromatography-tandem mass spectrometry method for the determination of zofenopril and its active metabolite zofenoprilat in human plasma

A novel, sensitive and rapid liquid chromatographic-electrospray ionization mass spectrometric method was developed and validated for the determination of zofenopril and its active metabolite zofenoprilat in human plasma. The method was based on a single extraction step using methyl tert-butyl ether and did not require chemical derivatization. The chromatographic conditions were optimized; separation was performed on a phenyl-hexyl column (5μm, 250mm×4.6mm i.d.) with a mobile phase consisting of a solution of methanol and water (95:5, v/v) that also contained 0.1% of formic acid. A flow rate of 1.0mL/min was used. Zofenopril, zofenoprilat and the internal standard (IS) fosinopril sodium were measured using an electrospray ion source in a positive reaction monitoring mode. Linear calibration curves were generated for zofenopril concentrations between 0.1052 and 1052ng/mL and for zofenoprilat concentrations between 0.2508 and 2508ng/mL. In both cases, the coefficients of determination were greater than 0.995. The extraction recovery for zofenopril was 93.5% on average. It was 92.5% for zofenoprilat. The inter- and intra-batch precision and accuracy for both zofenopril and zofenoprilat were higher than 14%. The method was applied to measure the concentrations of zofenopril and zofenoprilat in plasma samples.     

Determination of fexofenadine in human plasma by LC-MS/MS and its application in pharmacokinetic study

This study presented a simple, rapid, and sensitive liquid chromatography analytical method employing tandem mass spectrometry (LC-MS/MS) to determine fexofenadine in human plasma. After the de-proteination procedure with acetonitrile, chromatographic separation of fexofenadine was performed using a reversed-phase Eclipse XDB-C₈ column with a mobile phase consisted of 1 mmol/L ammonium acetate buffer solution containing 0.2% formic acid-methanol (45:55, v/v). Fexofenadine was quantified using tandem mass detection in the electrospray ionization (ESI) positive ion mode. The flow rate of the mobile phase was 1 mL/min, and the retention times of fexofenadine and the internal standard (IS, losartan) were 1.76 min and 2.65 min, respectively. The calibration curve was linear over the plasma concentration range of 1-1000 ng/mL. The relative standard deviations of intra- and inter-batches were less than 10.4% and 15.4%, respectively. The LC-MS/MS method reported in this study showed higher sensitivity for the quantification of fexofenadine in human plasma than that shown by previously described analytical methods. Lastly, the method was successfully applied to the pharmacokinetic of fexofenadine in healthy Taiwan volunteers.     

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.     

高效液相离子对色谱法测定糖尿病大鼠血浆中二甲双胍浓度及其药代动力学研究(英文)

本研究建立并验证了测定糖尿病大鼠血浆中二甲双胍浓度的高效液相色谱方法,以阿替洛尔为内标,加入10%高氯酸沉淀蛋白来制备血浆样品。色谱条件:AQ-C18极限色谱柱(250mm×4.6mm,5μm),流动相(pH5.05)为乙腈-水(31:69,v/v,水相中含有0.002M十二烷基磺酸钠,0.0125M磷酸二氢钾,0.015M三乙胺),流速1.0mL/min。二甲双胍在7.5-4000ng/mL范围内具有良好的线性关系(r>0.994),最低检测限(LLOQ)为7.5ng/mL,描述精密度的相对标准偏差(RSD)范围为1.87%-15.70%,准确度为93.98%-106.89%。二甲双胍和内标的回收率分别为95.40%和95.31%。不同实验条件下质控样品的稳定性相对偏差范围在±9.00%之内。该方法成功地运用到糖尿病大鼠单剂量灌胃10mg/kg二甲双胍后的药代动力学研究中,结果显示本研究采用AQ-C18极限色谱柱建立的离子对色谱法对强极性化合物如二甲双胍具有良好的分离效果。     

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.     

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 .     

Establishment of a liquid chromatographic/mass spectrometry method for quantification of tetrandrine in rat plasma and its application to pharmacokinetic study

A rapid and sensitive liquid chromatography-tandem mass spectrometric method (LC/MS/MS) for the determination of tetrandrine in rat plasma has been developed, fully validated and successfully applied to pharmacokinetic study in Sprague-Dawley (SD) rats after a single oral administration. Sample preparation involves a liquid-liquid extraction with n-hexane-dichlormethane (65:35, containing 1% 2-propanol isopropyl alcohol, v/v). Tetrandrine and brodimoprim (internal standard) were well separated by LC with a Dikma C(18) column using acetonitrile-methanol-ammonium formate aqueous solution (20mM) containing 0.3% formic acid (20:30:50, v/v/v) as mobile phase. Detection was performed on a triple quadrupole mass spectrometer in multiple reaction monitoring mode. The ionization was optimized using ESI(+) and selectivity was achieved using MS/MS analysis, m/z 623.0-->381.0 and m/z 339.0-->281.0 for tetrandrine and I.S., respectively. The present method exhibited good linearity over the concentration range of 5-2,000 ng/mL for tetrandrine in rat plasma with a lower limit of quantification of 5 ng/mL. The intra- and inter-day precision were 2.0-9.2% and 4.5-9.4%, and the intra- and inter-day accuracy ranged from -7.6 to 10.3% and -6.0 to 5.3%, respectively. No endogenous compounds were found to interfere with the analysis, and tetrandrine was stable during the whole assay period. The method was successfully applied to a pharmacokinetic study after an intragastric administration (i.g.) of tetrandrine to SD rats with a single dose of 50mg/kg. The results confirm that the assay is suitable for the pharmacokinetic study of tetrandrine.     

Liquid chromatography-tandem mass spectrometry method for the determination of trimetazidine in human plasma

A sensitive liquid chromatography-tandem mass spectrometry (LC/MS/MS) method was developed and validated for the determination of trimetazidine (CAS 13171-25-0) in human plasma, using pseudoephedrine as internal standard (IS). Plasma samples were simply pretreated with methanol for deproteinization. The chromatographic separation was performed on a C18 column with a mobile phase of 3 mmol/L ammonium acetate solution-methanol (15:85, v/v) at a flow rate of 0.3 mL/min. The chromatographic separation was achieved in less than 3.2 min. The linearity was established over the concentration range of 1-100 ng/mL. Both intra- and inter-batch standard deviations were less than 9.5%. The method was successfully applied to study the relative bioavailability of trimetazidine hydrochloride tablets in healthy Chinese volunteers and the pharmacokinetic parameters of the reference and test tablets were compared.     

LC-MS/MS 法测定人血浆中倍他米松

建立测定人血浆中倍他米松的LC-MS/MS方法。采用Venusil XBP C₈ (200 mm×3.9 mm ID, 5 μm)色谱柱，流动相为甲醇-水(含甲酸铵5 mmol·L^-1)(80∶20)，流速0.4 mL·min^-1；质谱仪离子源为电喷雾离子源(ESI)，正离子模式检测，监测离子为393.3→355.2(倍他米松)和361.3→343.2(泼尼松龙,内标)。血浆样本用乙酸乙酯处理。倍他米松在0.5~80.0 ng·mL^-1线性关系良好(r=0.999 2)， 血浆低、 中、 高3种浓度(1.0， 10.0， 60.0 ng·mL^-1)平均提取回收率为88.24%，定量限为0.5 ng·mL^-1。本方法操作简便、准确、灵敏，适用于复方倍他米松注射液人体药代动力学研究。     

Simultaneous Quantification of Baricitinib and Methotrexate in Rat Plasma by LC-MS/MS: Application to a Pharmacokinetic Study

Efficacy assessments using a combination of baricitinib and methotrexate necessitate the development of an analytical method for the determination of both drugs in plasma with precision. A high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous determination of baricitinib and methotrexate in rat plasma. Extraction of baricitinib, methotrexate, and tolbutamide (internal standard; IS) from 50 µL of rat plasma was carried out by protein precipitation with methanol. Chromatographic separation of the analytes was performed on the YMC pack ODS AM (150 mm × 4.6 mm, 5 µm) column under gradient conditions with methanol: 2.0 mM ammonium acetate buffer as the mobile phases at a flow rate of 1 mL/min. The precursor ion and product ion transition for both analytes and IS were monitored on a triple quadrupole mass spectrometer, operated with selective reaction monitoring in positive ionization mode. The method was validated over a concentration range of 0.5–250.00 ng/mL for baricitinib and methotrexate. Mean extraction recoveries for baricitinib, methotrexate, and IS of 86.8%, 89.4%, and 91.8% were consistent across low, medium, and high QC levels, respectively. Precision and accuracy at low, medium, and high quality control levels were less than 15% across the analytes. Benchtop, wet, freeze-thaw, and long-term stability were evaluated for both of the analytes. The analytical method was applied to support the pharmacokinetic study of simultaneous estimation of baricitinib and methotrexate in Wistar rats. Assay reproducibility was demonstrated by reanalysis of 18 incurred samples     

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法检测人血浆中甲基纳曲酮浓度的分析方法及其应用

目的:建立快速、灵敏、可靠的LC-MS/MS法测定人血浆中甲基纳曲酮的浓度.方法:采用弱阳离子交换固相萃取柱进行样品预处理,以溴甲基纳曲酮-d3为内标,通过Ultra PFP Propyl柱(100mm×2.1 mm,5.0 μm)色谱柱进行分离,流动相为20 mmol·L-1乙酸铵水溶液(含1％甲酸)和乙腈,等度洗脱...     

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.