Rapid ultraperformance liquid chromatography-tandem mass spectrometry method for quantification of oxcarbazepine and its metabolite in human plasma.
Authors: Mitesh Bhatt, Sanjay Shah, and Shivprakash.
BIOMEDICAL CHROMATOGRAPHY (Accepted on 30 june,2010. DOI:10.1002/bmc.1510)
Development of a high-throughput method fot the determination of ethosuximide in human plasma by plasma Liquid Chromatography mass spectrometry.
Authors: Mitesh Bhatt, Sanjay Shah, and Shivprakash.
BIOMEDICAL CHROMATOGRAPHY B 2010, 878: 1605–1610
Development and Validation of amitriptyline and its metabolitein human plasma by plasma Liquid Chromatography-tandem mass spectrometry and its application to a bioequivalence study.
Authors: Mitesh Bhatt, Sanjay Shah, and Shivprakash.
BIOMEDICAL CHROMATOGRAPHY (Published online: 6 May,2010. DOI:10.1002/bmc.1435)
Determination of Quinapril and Quinaprilat in Human Plasma by Ultra Performance Liquid Chromatography-electrospray ionization mass spectrometry.
Authors: Bhavesh Dasandi, Sanjay Shah, and Shivprakash.
JOURNAL OF BIOMEDICAL CHROMATOGRAPHY 2009; 23: 492-498
Determination of Fenofibric acid in Human Plasma by Ultra Performance Liquid Chromatography-electrospray ionization mass spectrometry: Application to a bioequivalence study.
Authors: Bhavesh Dasandi, Sanjay Shah, and Shivprakash.
JOURNAL OF BIOMEDICAL CHROMATOGRAPHY 2009; 23: 922-928
Development and validation of a high throughput and robust LC-MS/MS with electrospray ionization method for simultaneous quantitation of Diltiazem and its two metabolites in human plasma: Application to a bioequivalence study.
Authors: Bhavesh Dasandi, Sanjay Shah, and Shivprakash.
CHROMATOGRAPHY B 2009; 877: 791-798.
Solid-phase extraction and analysis of paroxetine in human plasma by ultra performance liquid chromatography–electrospray ionization mass spectrometry
Authors: Mitesh Bhatta, Sanjay Shaha and Shivprakash.
JOURNAL OF BIOMEDICAL CHROMATOGRAPHY (online available :Jul 2009)
Sensitive and Rapid High Performance liquid chromatography Tandem mass spectrometry method for estimation of fulvestrant in Rabbit plasma.
Authors: Varanasi Murali Balaram, Dharmesh Parmar, Bulusu B Teja, Shivprakash and Jangala Venkateswara Rao, Bhavesh Dasandi.
JOURNAL OF BIOMEDICAL CHROMATOGRAPHY (accepted on 30 Oct 2009)
Development and Validation of LC-UV for Simultaneous estimation of rosiglitazone and Glimepiride in human Plasma.
Authors : Jahanvi N.Jingar, Sadhna J.Rajput, Bhavesh Dasandi, Shivprakash Rathnam.
CHROMATOGRAPHIA 2008, 67, 951-955.
Estimation and pharmacokinetics of metformin in human volunteers
Authors : D. Bhavesh, G. Chetan, K. M. Bhatt and Shivprakash
INDIAN J. PHARM. EDU.RES 41(2), Apr-Jun, 2007.
Abstract:
A simple and rapid HPLC assay method for the estimation of metformin in human plasma was developed and validated. The method totally eliminates the extraction procedure. The plasma proteins were precipitated using perchloric acid : acetonitrile (50%v/v) mixture and the supernatant liquid was removed, dried under nitrogen,reconstituted in mobile phase and injected into the HPLC system. The separation was achieved with a cationic exchange column (Hihchrom, 250X4.6mm) with mobile phase of methanol: potassium di-hydrogen orthophosphate buffer (0.1M, pH 3.5) mixture 46 : 54 % v/v and elevated temperature of 40 0 C. Detection was by UV detector at 236nm. The retention time (RT) observed are at around 13 and 16 minutes for metformin and phenformin respectively. The response was linear over a range of 30-5000 ng ml-1. The same method was used for the bioequivalence study of two metformin formulations in healthy, human, Indian, male volunteers.
Simultaneous Quantitation of Estradiol and Estrone in Human Plasma by Liquid Chromatography-Tandem Mass Spectrometry with Electrospray Ionization
Authors : Shivprakash, P.Shruti, Dasandi B, Panchal A, Jansari P.and Prashanthkumar V.
INDIAN DRUGS 44(3) MARCH 2007.
Abstract:
A simple, rapid, sensitive liquid chromatography-tandem mass spectrometry method was developed and validated for simultaneous analysis of endogenous estradiol and estrone in human plasma. The analytes were extracted by liquid-liquid extraction with dicholormethane, whcih was then evaporated and derivatized with dansyl chloride, and injected into the LC/MS/MS system. THe chromatographic separation was performed and on revere phase sunfire C18 column with a mobile phase comprising formic acid and acetonitrile in gradient mode. The mass transitions of m/z 506.12/170.66 for 3-dansyl-estradiol, m/z 504.10/170.66 for 3-dansyl estrone were monitored usng multiple reaction-monitoring (MRM) modes for quantification. With the optimumtuning parameters, the lower level of quantification for estradiol in human plasma was 15.64 pg mL-1 and 16.0 mL-1 for estrone and estradiol, respectively. Acceptable precision and accuracy were obtained for concentrations over the standard curve range of 15-1250 pg Ml-1. This procedure could potentially be used in the investigation of estrogen for pathophysilogical assessment and other clinical appliations, including pharmacokinetic studies.
Formulations Dependent Variability in The Pharmacokinetics: A Case Study With Metformin
Authors : Shubha Rani, Monica Verma, Shivprakash, Harish Padh
World Journal of Medical Sciences 1(1), 2006, 9-13
Abstract:
A retrospective analysis was carried out to compare the bioavailability of variety of preparations of metformin using the data of four bioequivalence studies of metfomin formulations. Four separate bioequivalence studies have been investigated where a single dose of the specific formulation was administered to 12 healthy, male Asian Indian volunteers. Three studies (Studies 1, 2 and 3) were done after an overnight fast whereas one study (no. 4) was conducted in fed condition. Our findings illustrate that the three formulations used in studies 1 and 2 showed comparable plasma concentration – time profiles and four formulations used in studies 3 and 4 demonstrated comparable maximum plasma concentration (Cmax), area under the curve from 0 hr to time t (AUC0-t) and area under the curve from 0 hr to time ¥ (AUC0-¥). The results infer that the same dose of drug gives different plasma concentration-time profiles of the drug if different marketed formulations are being used. Hence metformin may have variable results, including adverse drug reaction or therapeutic failure, as it has formulation dependent pharmacokinetics.
Determination and Validation of an LC Method of Bendroflumethiazide in Human Plasma and its Pharmacokinetics
Authors : D. Bhavesh, P. Srinivasa, P Parag, P Brijesh, R. Shivprakash, V. Prasanthkumar
CHROMATOGRAPHIA 2006, 63, 243-248
Abstract:
A simple and rapid HPLC assay method for the estimation of metformin in human plasma was developed and validated. The method totally eliminates the extraction procedure. The plasma proteins were precipitated using perchloric acid : acetonitrile (50%v/v) mixture and the supernatant liquid was removed, dried under nitrogen,reconstituted in mobile phase and injected into the HPLC system. The separation was achieved with a cationic exchange column (Hihchrom, 250X4.6mm) with mobile phase of methanol: potassium di-hydrogen orthophosphate buffer (0.1M, pH 3.5) mixture 46 : 54 % v/v and elevated temperature of 40 0 C. Detection was by UV detector at 236nm. The retention time (RT) observed are at around 13 and 16 minutes for metformin and phenformin respectively. The response was linear over a range of 30-5000 ng ml-1. The same method was used for the bioequivalence study of two metformin formulations in healthy, human, Indian, male volunteers.
LC determination and pharmacokinetics of Meloxicam
Authors : Bhavesh Dasandi, Shivprakash, Saroj H., K M Bhatt J.Pharm.
Biomed Ana, [28(2002)999-1004]
Abstract:
A simple and rapid HPCL assay method for the estimation of meloxicam in plasma was developed .The method totally eliminated the solvent extraction procedure. The plasma proteins were precipitated using perchloric acid(70%) and acetonitrile mixture (1:1v/v)and the supernatant was directly injected to the HPCL system.The Separation was achieved on a Lichrospher C18 5µ(125*4.0mm)analytical column with a mobile phase of sodium acetate buffer (pH 3.3 ,170 mmol)acetonitrile (62.38v/v)mixture.Detection was by UV detector at 355 nm.The retention time observed for meloxicam and piroxicam (internal standard)were at 6.0 and 4.0 min ,repectively . The response was linear over a range of 50 – 1500 ng ml -1 in human plasma .The method was simple, specific, precise and accurate . The method was also used for the bioequivalence study of meloxicam formulation in healthy human Indian, male valunteers.
© 2002 Elsevier Science B.V. All rights reserved.
Determination of DOXAZOSIN in human plasma by reversed phase ion-pair HPLC with fluorescence Detection
Authors : D. Bhavesh, S.Pinal, V.Saroj, Shivprakash
Indian Journal of Pharmaceutical science [2002,64,(4):354-356]
Abstract:
A high performance liquid chromatographic method was develpoed for the estimation of doxazosin in human plasma . It employs a simple and rapid method of sample preparation . Doxazosin and intenal standard (prazosin)were chromatographed as ion pairs with heptane sulphonic acid. Sample preparation involved liquid-liquid extraction with diethylether, evaporation of the organic layer reconstitution of the residue into mobile phase and injection of 20 µl into the chromatograph.Chromatograph was performed using ODS C18 5µ reverse phase column with fluorescence detection.Mobile phase consisted of heptane sulphonic acid buffer and methanol. At a flow rate of 1.2 ml/min,one analysis was completed in less than10min . The method was sensitive and reproducibel with accurate detecation as low as 0.1 ng/ml in plasma . The method was linear for doxazosin concentrations in the range of 0.5 -30 ng/ml (r2 =0.9976). Recoveries for the same drug concentrations from spiked human plasma ranged from 90-95% (n=5). The mean RSD values for interdaya and intraday assay reproducibility (n=5) were 4.47 % and 4.52 % respecively. Peak area ratios were fit to a least squares liner regression algorithm with a 2/x weighting . LOD and LOQ of the method were found to be 0.1 ng/ml and 0.5 ng/ml respectively.
Development of HPLC assay method for the estimation of Olanzapine in human plasma and its application to pharmacokinetics
Authors : Dasandi Bhavesh, Shah Pinal, Gandhi Chetan, Bhatt K.M., Shivprakash
INDIAN DRUGS 40(6) JUNE 2003, 350-354
Accepted for publication in Indian Drugs,
Won Best research paper award from Indian Drugs Manufacturers Associations.
Abstract:
A new method for the estimation of olanizapine in human plasma is developed and validated . It utilizes RP select B column and amperometric detector . The mobile phase consisted of 75mM sodium dihydrogen phospate buffer of pH 7.0 acetonitrile and method in 55:22.5:22.5% v/v ratios in an isocratic mode at 1.5 ml-1 flow rate .The drug is extracted in to 3ml each of Tertiary Butyl Methyl Ether (TBME)twice form plasma evaporated and the residue dissolved in mobile phase . The percentage extraction is found to be more than 79% and the linearity range from 0.5ng to 50.0ng ml-1. The method has been validated extensively and found to have good interday and intraday precision. This method has been applied to study pharmacokinetics in 12 healty human volunteers.
LC method for the estimation of Cefprozil in human plazma and its pharmacokinetics
Authors : Shivprakash, Reddy, Dasandi B., Patel C., Bhat K.M.
Indian Drugs 41(2), February 2004.
Abstract:
A new method for the estimation of Cefprozil is developed and validated. This method is simple and rapid because the sample preparation is devoid of any solvent extraction. The plasma proteins were precipitated and the supernatant was directly injected to the HPCL system. The separation was achieved using RP 18e (5µ, 250* 4 mm) column and the mobile phase was a mixture of Phosphate buffer and acetonitrile. The eluents monitored at 235 nm. The column was maintained at a temperature of 40+ 0.1 oC. The method was validated for sensitivity, specificity precision and accuracy. The LOQ of thid method is 0.25µg ml1 and the calibration curve range is 0.25 to 30µg ml-1. This method is used to study the comparative bioavailability of conventional and sustained release capsules of Cefprozil.
Bioequivalence: Issues and perspectives
Author: Shubha Rani
Indian J Phannacol I October 2007 I Vol 39 I Issue 5 I 218-225
Abstract:
The design, performance and evaluation of bioavailability and bioequivalence have evolved over the last two decades. Bioequivalence (BE) means the absence of a greaterthan-allowable difference between the systemic bioavailability of a test product and that of a reference product. Due to efforts by academia, the pharmaceutical industry and health authorities, there is far-reaching consensus on essential questions of bioequivalence trials which have been reflected in the many regulatory guidelines. Despite the introduction and wide acceptance of stringent requirements for bioequivalence studies, there is, however, increasing awareness that some fundamentals of bioequivalence assessment need to be reconsidered in principal. This includes several debatable issues such as practical strategies for bioequivalence of highly variable drugs, drugs with long half life, drugs under genetic polymorphic metabolism, biopharmaceuticals and endogenous substances; single bioequivalence range for all drugs; inclusion of female volunteers; individual versus average bioequivalence; metrics of absorption; etc. This article is an attempt to highlight current thinking on issues in bioequivalence.