A sensitive and rapid liquid chromatography-tandem mass spectrometry(LC–MS/MS) method has been developed for the simultaneous determination of lisinopril(LIS) and hydrochlorothiazide(HCTZ) in human plasma using their...A sensitive and rapid liquid chromatography-tandem mass spectrometry(LC–MS/MS) method has been developed for the simultaneous determination of lisinopril(LIS) and hydrochlorothiazide(HCTZ) in human plasma using their labeled internal standards(ISs). Sample pre-treatment involved solid phase extraction on Waters Oasis HLB cartridges using 100 μL of plasma, followed by liquid chromatography on Hypersil Gold C_(18)(50 mm×3.0 mm, 5 μm) column. The analytes were eluted within 2.0 min using acetonitrile-5.0 m M ammonium formate, p H 4.5(85:15, v/v) as the mobile phase. The analytes and ISs were analyzed in the negative ionization mode and quantified using multiple reaction monitoring. The method showed excellent linearity over the concentration range of 0.50–250.0 ng/m L for both the analytes. The intra-batch and inter-batch precision(% CV) was ≤5.26% and their extraction recoveries were in the range of 96.6%–103.1%. Matrix effect evaluated in terms of IS-normalized matrix factors ranged from 0.97 to 1.03 for both the analytes. The validated method was successfully applied to determine the plasma concentration of the drugs using 10 mg lisinopril and 12.5 mg hydrochlorothiazide fixed dose formulation in 18 healthy Indian volunteers.展开更多
A sensitive and selective method has been proposed for the simultaneous determination of amlodipine(AML),valsartan(VAL) and hydrochlorothiazide(HCTZ) in human plasma by liquid chromatography–tandem mass spectrometry...A sensitive and selective method has been proposed for the simultaneous determination of amlodipine(AML),valsartan(VAL) and hydrochlorothiazide(HCTZ) in human plasma by liquid chromatography–tandem mass spectrometry(LC–MS/MS). The analytes and their deuterated analogs were quantitatively extracted from100 μL human plasma by solid phase extraction on Oasis HLB cartridges. The chromatographic separation of the analytes was achieved on a Chromolith RP18 e(100 mm × 4.6 mm) analytical column within 2.5 min. The resolution factor between AML and VAL, AML and HCTZ, and VAL and HCTZ was 2.9, 1.5 and 1.4, respectively,under isocratic conditions. The method was validated over a dynamic concentration range of 0.02–20.0 ng/m L for AML, 5.00–10,000 ng/m L for VAL and 0.20–200 ng/m L for HCTZ. Ion-suppression/enhancement effects were investigated by post-column infusion technique. The mean IS-normalized matrix factors for AML, VAL and HCTZ were 0.992, 0.994 and 0.998, respectively. The intra-batch and inter-batch precision(% CV) across quality control levels was ≤ 5.56% and the recovery was in the range of 93.4%–99.6% for all the analytes. The method was successfully applied to a bioequivalence study of 5 mg AML + 160 mg VAL + 12.5 mg HCTZ tablet formulation(test and reference) in 18 healthy Indian males under fasting. The mean log-transformed ratios of C max, AUC0–120 h and AUC0-inf and their 90% CIs were within 90.2%–102.1%. The assay reproducibility was demonstrated by reanalysis of 90 incurred samples.展开更多
An improved and reliable ultra-performance liquid chromatography/tandem mass spectrometry （UPLC- MS/MS） method has been developed and validated for the determination of lercanidipine in human plasma. Plasma samples ...An improved and reliable ultra-performance liquid chromatography/tandem mass spectrometry （UPLC- MS/MS） method has been developed and validated for the determination of lercanidipine in human plasma. Plasma samples with lercanidipine-d3 as an internal standard （IS） were prepared by solid phase extraction on Phenomenex Strata-X cartridges using 100 μL of human plasma. Chromatographic analysis was performed on UPLC BEH C18 （50 mm × 2.1 mm, 1.7 μm） column under isocratic conditions. Linear calibration curves were obtained over a wide dynamic concentration range of 0.010-20.0 ng/mL. Matrix effect was assessed by post-column infusion, post-extraction spiking and standard-line slope methods. The mean extraction recovery was 〉 94% for the analyte and IS. Inter-batch and intra-hatch precision （% CV） across five quality controls was 〈 5.8%. Bioequivalence study was performed with 36 healthy sub- jects after oral administration of 10 mg of lercanidipine and the assay reproducibility was evaluated by reanalysis of 133 incurred samples.展开更多
A selective, sensitive and precise assay based on solid phase extraction and liquid chromatography–tandem mass spectrometry(LC–MS/MS) was developed for the simultaneous determination of amiloride(AMI) and hydrochlor...A selective, sensitive and precise assay based on solid phase extraction and liquid chromatography–tandem mass spectrometry(LC–MS/MS) was developed for the simultaneous determination of amiloride(AMI) and hydrochlorothiazide(HCTZ) in human plasma. Sample clean-up with 250 μL of plasma was done on Phenomenex Strata^(?)-X extraction cartridges using their labeled internal standards(AMI-15 N3 and HCTZ-13 C,d2). Chromatography was performed on Hypersil Gold C18(50 mm×3.0 mm, 5 μm) column using acetonitrile with 4.0 m M ammonium formate(p H 4.0, adjusted with 0.1% formic acid)(80:20, v/v) as the mobile phase. Detection was carried out on a triple quadrupole API 5500 mass spectrometer utilizing an electrospray ionization interface and operating in the positive ionization mode for AMI and negative ionization mode for HCTZ. Multiple reaction monitoring was used following the transitions at m/z 230.6/116.0, m/z233.6/116.0, m/z 296.0/204.9 and m/z 299.0/205.9 for AMI, AMI-15 N3, HCTZ and HCTZ-13 C,d2,respectively. Calibration curves were linear(r2≥0.9997) over the concentration range of 0.050–50.0 and0.50–500 ng/m L for AMI and HCTZ, respectively, with acceptable accuracy and precision. The signal-to-noise ratio at the limit of quantitation was ≥14 for both the analytes. The mean recovery of AMI and HCTZ from plasma was 89.0% and 98.7%, respectively. The IS-normalized matrix factors determined for matrix effect ranged from 0.971 to 1.024 for both the analytes. The validated LC–MS/MS method was successfully applied to a bioequivalence study using 5 mg AMI and 50 mg HCTZ fixed dose tablet formulation in 18 healthy Indian volunteers with good reproducibility.展开更多
Enantioseparation of threeβ-blockers,i.e.,atenolol,metoprolol and propranolol,was studied on amylose tris(3-chloro-5-methylphenylcarbamate)immobilized chiral stationary phase using supercritical fluid chromatography(...Enantioseparation of threeβ-blockers,i.e.,atenolol,metoprolol and propranolol,was studied on amylose tris(3-chloro-5-methylphenylcarbamate)immobilized chiral stationary phase using supercritical fluid chromatography(SFC).The effect of organic modifiers(methanol,isopropanol and their mixture),column temperature and back pressure on chiral separation ofβ-blockers was evaluated.Optimum chromatographic separation with respect to resolution,retention,and analysis time was achieved using a mixture of CO_(2) and 0.1%isopropyl amine in isopropanol:methanol(50:50,V/V),in 75:25(V/V)ratio.Under the optimized conditions,the resolution factors(Rs)and separation factors(a)were greater than3.0 and 1.5,respectively.Further,with increase in temperature(25-45℃)and pressure(100-150 bars)there was corresponding decrease in retention factors(k),a and Rs.However,a reverse trend(a and Rs)was observed for atenolol with increase in temperature.The thermodynamic data from van’t Hoff plots revealed that the enantioseparation was enthalpy driven for metoprolol and propranolol while entropy driven for atenolol.To understand the mechanism of chiral recognition and the elution behavior of the enantiomers,molecular docking studies were performed.The binding energies obtained from simulation studies were in good agreement with the elution order found experimentally and also with the free energy values.The method was validated in the concentration range of 0.5-10μg/m L for all the enantiomers.The limit of detection and limit of quantitation ranged from 0.126 to 0.137μg/m L and 0.376-0.414μg/m L,respectively.The method was used successfully to analyze these drugs in pharmaceutical preparations.展开更多
A rapid and sensitive ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)method is described for determination of letrozole in human plasma.Following solid phase extraction(SPE)of letrozole an...A rapid and sensitive ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)method is described for determination of letrozole in human plasma.Following solid phase extraction(SPE)of letrozole and letrozole-d4 on Orochem DVB-LP cartridges,chromatography was performed on Acquity UPLC BEH C_(18)(50 mm×2.1 mm.1.7μm)column using methanol-0.1%formic acid in water(85:15,v/v)as the mobile phase.Detection was carried out on a triple quadrupole mass spectrometer with an electrospray source,operated under positive ionization mode.Quantitation of letrozole and letrozole-d4 was done using multiple reaction monitoring(MRM)following the transitions at m/z286.2→217.0 and m/z 290.2→221.0,respectively.The calibration plots were linear through the concentration range of 0.10-100 ng/mL(r^2≥0.9990)using 100μL human plasma.The extraction recovery of letrozole ranged from 94.3%to 96.2%and the intra-batch and inter-batch precision was≤5.2%.The method was successfully applied to a bioequivalence study of letrozole after oral administration of2.5 mg tablet formulation to 16 healthy postmenopausal Indian women.The assay reproducibility was also established through incurred sample reanalysis(ISR)of 74 subject samples.展开更多
A selective and rapid high-performance liquid chromatography–tandem mass spectrometry method was developed and validated for the quantification of raltegravir using raltegravir-d3 as an internal standard（IS）. The a...A selective and rapid high-performance liquid chromatography–tandem mass spectrometry method was developed and validated for the quantification of raltegravir using raltegravir-d3 as an internal standard（IS）. The analyte and IS were extracted with methylene chloride and n-hexane solvent mixture from 100 mL human plasma. The chromatographic separation was achieved on a Chromolith RP-18 e endcapped C18（100 mm 4.6 mm） column in a run time of 2.0 min. Quantitation was performed in the negative ionization mode using the transitions of m/z 443.1-316.1 for raltegravir and m/z 446.1-319.0 for IS. The linearity of the method was established in the concentration range of 2.0–6000 ng/m L.The mean extraction recovery for raltegravir and IS was 92.6% and 91.8%, respectively, and the IS-normalized matrix factors for raltegravir ranged from 0.992 to 0.999. The application of this method was demonstrated by a bioequivalence study on 18 healthy subjects.展开更多
基金University Grants Commission (UGC), New Delhi, India for BSR fellowship F 4-1/2009 (BSR)/7-74/2007the Department of Chemistry, Gujarat University
文摘A sensitive and rapid liquid chromatography-tandem mass spectrometry(LC–MS/MS) method has been developed for the simultaneous determination of lisinopril(LIS) and hydrochlorothiazide(HCTZ) in human plasma using their labeled internal standards(ISs). Sample pre-treatment involved solid phase extraction on Waters Oasis HLB cartridges using 100 μL of plasma, followed by liquid chromatography on Hypersil Gold C_(18)(50 mm×3.0 mm, 5 μm) column. The analytes were eluted within 2.0 min using acetonitrile-5.0 m M ammonium formate, p H 4.5(85:15, v/v) as the mobile phase. The analytes and ISs were analyzed in the negative ionization mode and quantified using multiple reaction monitoring. The method showed excellent linearity over the concentration range of 0.50–250.0 ng/m L for both the analytes. The intra-batch and inter-batch precision(% CV) was ≤5.26% and their extraction recoveries were in the range of 96.6%–103.1%. Matrix effect evaluated in terms of IS-normalized matrix factors ranged from 0.97 to 1.03 for both the analytes. The validated method was successfully applied to determine the plasma concentration of the drugs using 10 mg lisinopril and 12.5 mg hydrochlorothiazide fixed dose formulation in 18 healthy Indian volunteers.
文摘A sensitive and selective method has been proposed for the simultaneous determination of amlodipine(AML),valsartan(VAL) and hydrochlorothiazide(HCTZ) in human plasma by liquid chromatography–tandem mass spectrometry(LC–MS/MS). The analytes and their deuterated analogs were quantitatively extracted from100 μL human plasma by solid phase extraction on Oasis HLB cartridges. The chromatographic separation of the analytes was achieved on a Chromolith RP18 e(100 mm × 4.6 mm) analytical column within 2.5 min. The resolution factor between AML and VAL, AML and HCTZ, and VAL and HCTZ was 2.9, 1.5 and 1.4, respectively,under isocratic conditions. The method was validated over a dynamic concentration range of 0.02–20.0 ng/m L for AML, 5.00–10,000 ng/m L for VAL and 0.20–200 ng/m L for HCTZ. Ion-suppression/enhancement effects were investigated by post-column infusion technique. The mean IS-normalized matrix factors for AML, VAL and HCTZ were 0.992, 0.994 and 0.998, respectively. The intra-batch and inter-batch precision(% CV) across quality control levels was ≤ 5.56% and the recovery was in the range of 93.4%–99.6% for all the analytes. The method was successfully applied to a bioequivalence study of 5 mg AML + 160 mg VAL + 12.5 mg HCTZ tablet formulation(test and reference) in 18 healthy Indian males under fasting. The mean log-transformed ratios of C max, AUC0–120 h and AUC0-inf and their 90% CIs were within 90.2%–102.1%. The assay reproducibility was demonstrated by reanalysis of 90 incurred samples.
基金UGC-BSR (F 4-1/2009 (BSR)/7-74/2007)New Delhi, for research fellowship, F 4-1/2009 (BSR)/7-74/2007Department of Chemistry, Gujarat University, for supporting this work
文摘An improved and reliable ultra-performance liquid chromatography/tandem mass spectrometry （UPLC- MS/MS） method has been developed and validated for the determination of lercanidipine in human plasma. Plasma samples with lercanidipine-d3 as an internal standard （IS） were prepared by solid phase extraction on Phenomenex Strata-X cartridges using 100 μL of human plasma. Chromatographic analysis was performed on UPLC BEH C18 （50 mm × 2.1 mm, 1.7 μm） column under isocratic conditions. Linear calibration curves were obtained over a wide dynamic concentration range of 0.010-20.0 ng/mL. Matrix effect was assessed by post-column infusion, post-extraction spiking and standard-line slope methods. The mean extraction recovery was 〉 94% for the analyte and IS. Inter-batch and intra-hatch precision （% CV） across five quality controls was 〈 5.8%. Bioequivalence study was performed with 36 healthy sub- jects after oral administration of 10 mg of lercanidipine and the assay reproducibility was evaluated by reanalysis of 133 incurred samples.
文摘A selective, sensitive and precise assay based on solid phase extraction and liquid chromatography–tandem mass spectrometry(LC–MS/MS) was developed for the simultaneous determination of amiloride(AMI) and hydrochlorothiazide(HCTZ) in human plasma. Sample clean-up with 250 μL of plasma was done on Phenomenex Strata^(?)-X extraction cartridges using their labeled internal standards(AMI-15 N3 and HCTZ-13 C,d2). Chromatography was performed on Hypersil Gold C18(50 mm×3.0 mm, 5 μm) column using acetonitrile with 4.0 m M ammonium formate(p H 4.0, adjusted with 0.1% formic acid)(80:20, v/v) as the mobile phase. Detection was carried out on a triple quadrupole API 5500 mass spectrometer utilizing an electrospray ionization interface and operating in the positive ionization mode for AMI and negative ionization mode for HCTZ. Multiple reaction monitoring was used following the transitions at m/z 230.6/116.0, m/z233.6/116.0, m/z 296.0/204.9 and m/z 299.0/205.9 for AMI, AMI-15 N3, HCTZ and HCTZ-13 C,d2,respectively. Calibration curves were linear(r2≥0.9997) over the concentration range of 0.050–50.0 and0.50–500 ng/m L for AMI and HCTZ, respectively, with acceptable accuracy and precision. The signal-to-noise ratio at the limit of quantitation was ≥14 for both the analytes. The mean recovery of AMI and HCTZ from plasma was 89.0% and 98.7%, respectively. The IS-normalized matrix factors determined for matrix effect ranged from 0.971 to 1.024 for both the analytes. The validated LC–MS/MS method was successfully applied to a bioequivalence study using 5 mg AMI and 50 mg HCTZ fixed dose tablet formulation in 18 healthy Indian volunteers with good reproducibility.
基金Department of Chemistry,Gujarat University,for supporting this workHuman Resource Development GroupCouncil of Scientific&Industrial Research(CSIR),New Delhi,for Research Associate Fellowship(File No.:09/070(0058)2K18 EMR-I)。
文摘Enantioseparation of threeβ-blockers,i.e.,atenolol,metoprolol and propranolol,was studied on amylose tris(3-chloro-5-methylphenylcarbamate)immobilized chiral stationary phase using supercritical fluid chromatography(SFC).The effect of organic modifiers(methanol,isopropanol and their mixture),column temperature and back pressure on chiral separation ofβ-blockers was evaluated.Optimum chromatographic separation with respect to resolution,retention,and analysis time was achieved using a mixture of CO_(2) and 0.1%isopropyl amine in isopropanol:methanol(50:50,V/V),in 75:25(V/V)ratio.Under the optimized conditions,the resolution factors(Rs)and separation factors(a)were greater than3.0 and 1.5,respectively.Further,with increase in temperature(25-45℃)and pressure(100-150 bars)there was corresponding decrease in retention factors(k),a and Rs.However,a reverse trend(a and Rs)was observed for atenolol with increase in temperature.The thermodynamic data from van’t Hoff plots revealed that the enantioseparation was enthalpy driven for metoprolol and propranolol while entropy driven for atenolol.To understand the mechanism of chiral recognition and the elution behavior of the enantiomers,molecular docking studies were performed.The binding energies obtained from simulation studies were in good agreement with the elution order found experimentally and also with the free energy values.The method was validated in the concentration range of 0.5-10μg/m L for all the enantiomers.The limit of detection and limit of quantitation ranged from 0.126 to 0.137μg/m L and 0.376-0.414μg/m L,respectively.The method was used successfully to analyze these drugs in pharmaceutical preparations.
文摘A rapid and sensitive ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)method is described for determination of letrozole in human plasma.Following solid phase extraction(SPE)of letrozole and letrozole-d4 on Orochem DVB-LP cartridges,chromatography was performed on Acquity UPLC BEH C_(18)(50 mm×2.1 mm.1.7μm)column using methanol-0.1%formic acid in water(85:15,v/v)as the mobile phase.Detection was carried out on a triple quadrupole mass spectrometer with an electrospray source,operated under positive ionization mode.Quantitation of letrozole and letrozole-d4 was done using multiple reaction monitoring(MRM)following the transitions at m/z286.2→217.0 and m/z 290.2→221.0,respectively.The calibration plots were linear through the concentration range of 0.10-100 ng/mL(r^2≥0.9990)using 100μL human plasma.The extraction recovery of letrozole ranged from 94.3%to 96.2%and the intra-batch and inter-batch precision was≤5.2%.The method was successfully applied to a bioequivalence study of letrozole after oral administration of2.5 mg tablet formulation to 16 healthy postmenopausal Indian women.The assay reproducibility was also established through incurred sample reanalysis(ISR)of 74 subject samples.
文摘A selective and rapid high-performance liquid chromatography–tandem mass spectrometry method was developed and validated for the quantification of raltegravir using raltegravir-d3 as an internal standard（IS）. The analyte and IS were extracted with methylene chloride and n-hexane solvent mixture from 100 mL human plasma. The chromatographic separation was achieved on a Chromolith RP-18 e endcapped C18（100 mm 4.6 mm） column in a run time of 2.0 min. Quantitation was performed in the negative ionization mode using the transitions of m/z 443.1-316.1 for raltegravir and m/z 446.1-319.0 for IS. The linearity of the method was established in the concentration range of 2.0–6000 ng/m L.The mean extraction recovery for raltegravir and IS was 92.6% and 91.8%, respectively, and the IS-normalized matrix factors for raltegravir ranged from 0.992 to 0.999. The application of this method was demonstrated by a bioequivalence study on 18 healthy subjects.
