Obesity can be considered as a chronic illness of epidemic proportion and its incidents have increased exponentially in recent years.The use of anti-obesity drugs such as sibutramine is somewhat helpful.There is a nee...Obesity can be considered as a chronic illness of epidemic proportion and its incidents have increased exponentially in recent years.The use of anti-obesity drugs such as sibutramine is somewhat helpful.There is a need to quantify such drugs in biological samples,which is generally quite difficult.In this report,we developed and validated a simple,sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of sibutramine (SB) and its two metabolites N-des methyl sibutramine (DSB) and N-di desmethyl sibutramine (DDSB) in human plasma.Zorbax SBC18 (4.6 mm × 75 mm,3.5 μm,80 (A)) analytical column and 5 mM ammonium formate:acetonitrile (10∶90,v/v) mobile phase were used for chromatographic separation of SB,DSB and DDSB.Multiple reaction monitoring (MRM) in the positive mode was used to detect SB,DSB and DDSB at m/z 280.3/124.9,266.3/125.3 and 252.2/124.9,respectively.Liquid liquid extraction was used for the extraction of analytes and internal standard from human plasma.This method was validated over a linear concentration range of 10.0-10,000.0 pg/mL for SB,DSB and DDSB with correlation coefficients (r) of ≥0.9997.The drug and the two metabolites were stable in plasma samples.The validated method was successfully applied in a bioequivalence and pharmacokinetic study with human volunteers under fasting condition.展开更多
A simple, sensitive, and specific liquid chromatography tandem mass spectrometry (LC-MS/ MS) method was developed for the quantification of desloratadine (DL) in human plasma using desloratadine-d5 (DLD5) as an intern...A simple, sensitive, and specific liquid chromatography tandem mass spectrometry (LC-MS/ MS) method was developed for the quantification of desloratadine (DL) in human plasma using desloratadine-d5 (DLD5) as an internal standard (IS). Chromatographic separation was performed using an Xbridge C18 column (50 mm 4.6 mm, 5 mm) with an isocratic mobile phase composed of 10 mM ammonium formate: methanol (20:80, v/v), at a flow rate of 0.7 mL/min. DL and DLD5 were detected with proton adducts at m/z 311.2-259.2 and 316.2-264.3 in multiple reaction monitoring (MRM) positive modes, respectively. Liquid–liquid extraction (LLE) method was used to extract the drug and the IS. The method was validated over a linear concentration range of 5.0–5000.0 pg/mL with a correlation coefficient of (r2)Z0.9994. This method demonstrated intra- and inter-day precision within 0.7–2.0% and 0.7–2.7%, and an accuracy within 101.4–102.4%, and 99.5–104.8%. DL was found to be stable throughout the freeze–thaw cycles, bench-top, and postoperative stability studies. This method was successfully applied in the analysis of plasma samples following oral administration of DL (5 mg) in 35 healthy Indian male human volunteers under fasting conditions.展开更多
A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed for simultaneous quantification of ezetimibe and simvastatin in rat plasma. The deuterium isotopes： ezetimibe d4 an...A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed for simultaneous quantification of ezetimibe and simvastatin in rat plasma. The deuterium isotopes： ezetimibe d4 and simvastatin d6 were used as internal standards for ezetimibe and simvastatin, respectively. MS/MS detection involved a switch of electron spray ionization mode from negative to positive at retention time 3.01 rain. Samples were extracted from plasma by liquid-liquid extraction using tertiary butyl methyl ether. Chromatographic separation was achieved with Agilent Eclipse XBD-CIs column using mobile phase that consisted of a mixture of ammonium acetate （pH4.5; 10 mM）-acetonitrile （25：75 v/v）. The method was linear and validated over the concentration range of 0.2--40.0 ng/rnL for simvastatin and 0.05-15.0 ng/mL for ezetimibe. The transitions selected were m/z 408.3→271.1 and m/z 412.0→275.10 for ezetimibe and ezetimibe d4, and m/z 419.30 → 285.20 and rrdz 425.40 →199.20 for simvastatin and simvastatin d6. Intra- and inter-batch precisions for ezetimibe were 1.6-14.8% and 2.1-13.4%; and for simvastatin 0.94-9.56% and 0.79-12%, respectively. The proposed method was sensitive, selective, precise and accurate for the quantification of ezetimibe and simvastatin simultaneously in rat plasma. The method was successfully applied to a pharmacokinetic study by oral co-administration of ezetimibe and simvastatin in SD rats.展开更多
The most suitable bio-analytical method based on liquid liquid extraction has been developed and validated for quantification of Rasagiline in human plasma. Rasagiline-13C3 mesylate was used as an internal standard fo...The most suitable bio-analytical method based on liquid liquid extraction has been developed and validated for quantification of Rasagiline in human plasma. Rasagiline-13C3 mesylate was used as an internal standard for Rasagiline. Zorbax Eclipse Plus C18 （2.1 mm × 50 mm, 3.5 um） column provided chromatographic separation of analyte followed by detection with mass spectrometry. The method involved simple isocratic chromatographic condition and mass spectrometric detection in the positive ionization mode using an API-4000 system. The lotal run time was 3.0 min. The proposed method has been validated with the linear range of 5 12000 pg/mL for Rasagiline. The intra-run and inter-run precision values were within 1.3% 2.9% and 1.6% 2.2% respectively for Rasagiline. The overall recovery for Rasagiline and Rasagiline-13C3 mesylate analog was 96.9% and 96.7% respectively. This validated method was successfully applied to the bioequivalence and pharmacokinetic study of human volunteers under fasting condition.展开更多
Ciprofioxacin, commonly used in India as an anti-microbial for prolonged use in chronic and non-specific indications, may affect the bioavailability of the drug. The drug prescribed is commonly taken with multivitamin...Ciprofioxacin, commonly used in India as an anti-microbial for prolonged use in chronic and non-specific indications, may affect the bioavailability of the drug. The drug prescribed is commonly taken with multivitamins, calcium and milk. A simple and reliable analytical methodology obtaining a correlation with in vivo urinary excretion studies using UV and HPLC and in vitro dissolution studies （IVIVC） has shown a significant increase in elimination rate of ciprofloxacin co-administered with multivitamins, calcium and milk. Appreciable IVlVC results proved that dissolution studies could serve as an alternative to in vivo bioavailability and also support bio-waivers.展开更多
Despite tremendous strides in modern medicine stringent control over insulin resistance or restoration of normoglycemia has not yet been achieved.With the growth of molecular biology,omics technologies,docking studies...Despite tremendous strides in modern medicine stringent control over insulin resistance or restoration of normoglycemia has not yet been achieved.With the growth of molecular biology,omics technologies,docking studies,and in silico pharmacology,modulators of enzymes and receptors affecting the molecular pathogenesis of the disease are being considered as the latest targets for anti-diabetic therapy.Therapeutic molecular targets are now being developed basing on the up or down regulation of different signaling pathways affecting the disease.Phytosynergistic antidiabetic therapy is in vogue both with classical and non-classical medicinal systems.However its chemoprofiling,structural and pharmacokinetic validation awaits providing recognition to such formulations for international acceptance.Translational health research with its focus on benchside product development and its sequential transition to patient bedside puts the pharma RDs to a challenge to develop bio-waiver protocols.Pharmacokinetic simulation models and establishment of in vitro-in vivo correlation can help to replace in vivo bioavailability studies and provide means of quality control for scale up and post approval modification.Thisreview attempts to bring different shades highlighting phyto-synergy,molecular targeting of antidiabetic agents via different signaling pathways and bio-waiver studies under a single umbrella.展开更多
文摘Obesity can be considered as a chronic illness of epidemic proportion and its incidents have increased exponentially in recent years.The use of anti-obesity drugs such as sibutramine is somewhat helpful.There is a need to quantify such drugs in biological samples,which is generally quite difficult.In this report,we developed and validated a simple,sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of sibutramine (SB) and its two metabolites N-des methyl sibutramine (DSB) and N-di desmethyl sibutramine (DDSB) in human plasma.Zorbax SBC18 (4.6 mm × 75 mm,3.5 μm,80 (A)) analytical column and 5 mM ammonium formate:acetonitrile (10∶90,v/v) mobile phase were used for chromatographic separation of SB,DSB and DDSB.Multiple reaction monitoring (MRM) in the positive mode was used to detect SB,DSB and DDSB at m/z 280.3/124.9,266.3/125.3 and 252.2/124.9,respectively.Liquid liquid extraction was used for the extraction of analytes and internal standard from human plasma.This method was validated over a linear concentration range of 10.0-10,000.0 pg/mL for SB,DSB and DDSB with correlation coefficients (r) of ≥0.9997.The drug and the two metabolites were stable in plasma samples.The validated method was successfully applied in a bioequivalence and pharmacokinetic study with human volunteers under fasting condition.
基金support received(for providing literature survey)from IICT(Indian Institute of Chemical Technology),Hyderabad,Indiathe APL Research Center Pvt Ltd, Hyderabad, India
文摘A simple, sensitive, and specific liquid chromatography tandem mass spectrometry (LC-MS/ MS) method was developed for the quantification of desloratadine (DL) in human plasma using desloratadine-d5 (DLD5) as an internal standard (IS). Chromatographic separation was performed using an Xbridge C18 column (50 mm 4.6 mm, 5 mm) with an isocratic mobile phase composed of 10 mM ammonium formate: methanol (20:80, v/v), at a flow rate of 0.7 mL/min. DL and DLD5 were detected with proton adducts at m/z 311.2-259.2 and 316.2-264.3 in multiple reaction monitoring (MRM) positive modes, respectively. Liquid–liquid extraction (LLE) method was used to extract the drug and the IS. The method was validated over a linear concentration range of 5.0–5000.0 pg/mL with a correlation coefficient of (r2)Z0.9994. This method demonstrated intra- and inter-day precision within 0.7–2.0% and 0.7–2.7%, and an accuracy within 101.4–102.4%, and 99.5–104.8%. DL was found to be stable throughout the freeze–thaw cycles, bench-top, and postoperative stability studies. This method was successfully applied in the analysis of plasma samples following oral administration of DL (5 mg) in 35 healthy Indian male human volunteers under fasting conditions.
文摘A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed for simultaneous quantification of ezetimibe and simvastatin in rat plasma. The deuterium isotopes： ezetimibe d4 and simvastatin d6 were used as internal standards for ezetimibe and simvastatin, respectively. MS/MS detection involved a switch of electron spray ionization mode from negative to positive at retention time 3.01 rain. Samples were extracted from plasma by liquid-liquid extraction using tertiary butyl methyl ether. Chromatographic separation was achieved with Agilent Eclipse XBD-CIs column using mobile phase that consisted of a mixture of ammonium acetate （pH4.5; 10 mM）-acetonitrile （25：75 v/v）. The method was linear and validated over the concentration range of 0.2--40.0 ng/rnL for simvastatin and 0.05-15.0 ng/mL for ezetimibe. The transitions selected were m/z 408.3→271.1 and m/z 412.0→275.10 for ezetimibe and ezetimibe d4, and m/z 419.30 → 285.20 and rrdz 425.40 →199.20 for simvastatin and simvastatin d6. Intra- and inter-batch precisions for ezetimibe were 1.6-14.8% and 2.1-13.4%; and for simvastatin 0.94-9.56% and 0.79-12%, respectively. The proposed method was sensitive, selective, precise and accurate for the quantification of ezetimibe and simvastatin simultaneously in rat plasma. The method was successfully applied to a pharmacokinetic study by oral co-administration of ezetimibe and simvastatin in SD rats.
文摘The most suitable bio-analytical method based on liquid liquid extraction has been developed and validated for quantification of Rasagiline in human plasma. Rasagiline-13C3 mesylate was used as an internal standard for Rasagiline. Zorbax Eclipse Plus C18 （2.1 mm × 50 mm, 3.5 um） column provided chromatographic separation of analyte followed by detection with mass spectrometry. The method involved simple isocratic chromatographic condition and mass spectrometric detection in the positive ionization mode using an API-4000 system. The lotal run time was 3.0 min. The proposed method has been validated with the linear range of 5 12000 pg/mL for Rasagiline. The intra-run and inter-run precision values were within 1.3% 2.9% and 1.6% 2.2% respectively for Rasagiline. The overall recovery for Rasagiline and Rasagiline-13C3 mesylate analog was 96.9% and 96.7% respectively. This validated method was successfully applied to the bioequivalence and pharmacokinetic study of human volunteers under fasting condition.
文摘Ciprofioxacin, commonly used in India as an anti-microbial for prolonged use in chronic and non-specific indications, may affect the bioavailability of the drug. The drug prescribed is commonly taken with multivitamins, calcium and milk. A simple and reliable analytical methodology obtaining a correlation with in vivo urinary excretion studies using UV and HPLC and in vitro dissolution studies （IVIVC） has shown a significant increase in elimination rate of ciprofloxacin co-administered with multivitamins, calcium and milk. Appreciable IVlVC results proved that dissolution studies could serve as an alternative to in vivo bioavailability and also support bio-waivers.
文摘Despite tremendous strides in modern medicine stringent control over insulin resistance or restoration of normoglycemia has not yet been achieved.With the growth of molecular biology,omics technologies,docking studies,and in silico pharmacology,modulators of enzymes and receptors affecting the molecular pathogenesis of the disease are being considered as the latest targets for anti-diabetic therapy.Therapeutic molecular targets are now being developed basing on the up or down regulation of different signaling pathways affecting the disease.Phytosynergistic antidiabetic therapy is in vogue both with classical and non-classical medicinal systems.However its chemoprofiling,structural and pharmacokinetic validation awaits providing recognition to such formulations for international acceptance.Translational health research with its focus on benchside product development and its sequential transition to patient bedside puts the pharma RDs to a challenge to develop bio-waiver protocols.Pharmacokinetic simulation models and establishment of in vitro-in vivo correlation can help to replace in vivo bioavailability studies and provide means of quality control for scale up and post approval modification.Thisreview attempts to bring different shades highlighting phyto-synergy,molecular targeting of antidiabetic agents via different signaling pathways and bio-waiver studies under a single umbrella.
