Indian chromite ore production was 3.728 MT and ferrochrome alloy production was 1.0 MT during 20... more Indian chromite ore production was 3.728 MT and ferrochrome alloy production was 1.0 MT during 2016-17. More than 95% of it was mined from Sukinda valley in the state of Odisha. The current Sukinda chromite ore is friable in nature and generate a lot of fine material, thus more than 95% of mined ore is less than 5 mm size fraction. Agglomeration is necessary for utilizing these chromite fines before charging in a submerged arc furnace. Normal chromite agglomeration processes include briquetting, pelletizing or sintering. Presently many ferro-chrome plants make pellets utilizing the ore fines by grinding it to suitable finer size (say 60% < 45 μm) and pelletize them. However, pelletizing is only suitable for vary fine feed that requires energy intensive grinding, expensive binders, and energy-intensive induration of pellets using liquid or gaseous fuel. Overall, the pelletization process is very complex and cost-intensive. In some plants, briquetting (cold & environment friendly p...
Etude de la degradation de colorants alimentaires par des bacteries de la microflore intestinale ... more Etude de la degradation de colorants alimentaires par des bacteries de la microflore intestinale humaine. Les bacteries reduisent ces colorants azoiques et les transforment en amines. Il apparait egalement que les bacteries sont capables d'utiliser ces memes colorants comme seule source de carbone
Journal of Pharmaceutical and Biomedical Analysis, 2012
A rapid, simple, and sensitive high performance liquid chromatography-tandem mass spectrometry me... more A rapid, simple, and sensitive high performance liquid chromatography-tandem mass spectrometry method (LC-ESI-MS/MS) was developed and validated for the determination and pharmacokinetic investigation of choline (CL), active metabolite of citicoline in human plasma using metformin (MF) as IS. The chromatographic separation was performed on a reversed-phase Phenomenx Gemini C18 column with a mobile phase of methanol:water (containing 10 mM ammonium formate) (9:1, v/v). The calibration curves were linear over the range of 0.05-5 g/ml. The validated LC-ESI-MS/MS method was successfully applied for the evaluation of pharmacokinetic parameters and bioequivalence study of test and reference control release (CR) tablet preparation of citicoline 1000 mg after a single oral administration to all 12 healthy male volunteers.
A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was develo... more A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed and validated for quantification of metoprolol succinate (MPS) and amlodipine besylate (AM) using hydrochlorothiazide (HCTZ) as IS in human plasma. Both the drugs were extracted by simple liquid-liquid extraction with chloroform. The chromatographic separation was performed on a reversed-phase peerless basic C18 column with a mobile phase of methanol-water containing 0.5% formic acid (8:2, v/v). The protonated analyte was quantitated in positive ionization by multiple reaction monitoring with a mass spectrometer. The method was validated over the concentration range of 1-100 ng/ml for MPS and 1-15 ng/ml AM in human plasma. The MRM transition of m/z 268.10-103.10, m/z 409.10-334.20 and m/z 296.00-205.10 were used to measure MPS, AM and HCTZ (IS), respectively. This method was successfully applied to the pharmacokinetic study of fixed dose combination (FDC) of MPS and AM formulation product after an oral administration to Indian healthy human volunteers.
A highly sensitive liquid chromatographic-tandem mass spectrometric method (LC-MS-MS) is develope... more A highly sensitive liquid chromatographic-tandem mass spectrometric method (LC-MS-MS) is developed to quantitate ranolazine in human plasma. The analyte and internal standard tramadol are extracted from plasma by liquid-liquid extraction using diethyl ether-dichloromethane (60:40 v/v), and separated on a Zorbax extend C 18 column using methanol-10mM ammonium acetate (60:40 v/v, pH 4.0) at a flow of 1.0 mL/min. Detection is carried out by multiple reaction monitoring on a QtrapTM LC-MS-MS system with an electrospray ionization interface. The assay is linear over the range 10-5000 ng/mL with a limit of quantitation of 10 ng/mL and a lower limit of detection (S/N > 3) of 1 ng/mL. Intra-and inter-day precision are < 3.1% and < 2.8%, respectively, and the accuracy is in the range 96.7-101.6%. The validated method is successfully used to analyze the drug in samples of human plasma for pharmacokinetic studies. Experimental Chemicals and reagents Ranolazine hydrochloride (purity > 99.0%) and tramadol hydrochloride [internal standard (IS), purity > 99.
The pharmacokinetics of nitazoxanide (CAS 55981-09-4) and ofloxacin (CAS 82419-36-1) has been ext... more The pharmacokinetics of nitazoxanide (CAS 55981-09-4) and ofloxacin (CAS 82419-36-1) has been extensively evaluated in adult human volunteers individually after oral administration of tablet formulation. However, no published data is available regarding the combined pharmacokinetics and bioavailability of this particular fixed dose combination. In light of the above, a clinical study was designed to evaluate the bioequivalence of two fixed dose combination (FDC) products of two manufacturers containing nitazoxanide 500 mg and ofloxacin 200 mg in healthy Indian male volunteers. 24 healthy male volunteers (age 25 +/- 4.6 years; weight 74.5 +/- 7.87 kg) were enrolled in this study. Each subject received a Test fixed dose combination and a Reference fixed dose combination formulation in a randomized, single dose, fasting state, two period, crossover study design with a 1-week washout period between the doses. Extraction of the drugs from the plasma was carried out by precipitation method. Analysis of tizoxanide (active metabolite of nitazoxanide) and ofloxacin from plasma samples was done by a simple and sensitive HPLC method using UV detection developed in our laboratory. An analysis of variance was performed on the pharmacokinetic parameters Cmax, AUC(0-t), AUC(0-infinity). using general linear model (GLM) procedures in which sources of variation were subject, formulation, period. The results of this investigation indicated that there were no statistically significant differences between the two products in either the mean concentration-time profiles or in the obtained pharmacokinetic parameters. 90 % confidence limits for the log-transformed data of Cmax, AUC(0-t), AUC(0-infinity) were within the acceptable range of 0.80-1.25. Thus, these findings clearly indicate that the two products are bioequivalent in terms of rate and extent of drug absorption. Both the preparations were well tolerated with no adverse reactions seen throughout the study.
Lovastatin is a lipid-lowering agent indicated for primary hypercholesterolemia. This study has a... more Lovastatin is a lipid-lowering agent indicated for primary hypercholesterolemia. This study has assessed single-dosing pharmacokinetics of lovastatin and of its main metabolite, lovastatin beta-hydroxyacid, and has compared the pharmacokinetics of two formulations of lovastatin, a test lovastatin generic (LVSG), and a reference (mevinacor 40 MSD) preparation. The pharmacokinetics and bioequivalence of the two formulations of lovastatin were evaluated by a two-way cross-over randomized double blinded study, in 36 healthy volunteers after a single oral dose of 2 x 40 mg per subject. On plasma samples, collected at given intervals of time (0-24h), lovastatin and its main active metabolite were assayed by high pressure liquid chromatography with positive turbo ion spray ionization tandem mass spectrometry detection. The pharmacokinetic parameters, area under the curve total (AUC(t)) and to infinity (AUC(inf)), peak plasma concentration (C(max)), time to attain peak (t(max)), and elimination half-life (t(1/2)) were determined and analyzed statistically. Only minor differences in the pharmacokinetics of lovastatin and lovastatin hydroxyacid between LVSG and mevinacor were found. Analysis of variance (ANOVA) did not show any significant difference between the two formulations, and 90% confidence intervals fell within the acceptable range for bioequivalence. The tolerability profile was good and comparable for the two formulations of lovastatin. Our study, which was performed with the largest number of subjects compared with those published in literature, indicates the bioequivalence of LVSG and mevinacor tablets. The high inter-subject variability of parameters investigated indicate the need of appropriate sample size in pharmacokinetics studies with lovastatin.
A sensitive and selective liquid chromatographic tandem mass spectrometric (LCMSMS) method was ... more A sensitive and selective liquid chromatographic tandem mass spectrometric (LCMSMS) method was developed for simultaneous identification and quantification of tamsulosin and dutasteride in human plasma, which was well applied to clinical study. The method was based on ...
A bioanalytical method has been developed and validated for determination of pregabalin in human ... more A bioanalytical method has been developed and validated for determination of pregabalin in human plasma. The analytical method consists in the precipitation of plasma sample with trichloro acetic acid (20% v/v solution in water), followed by the determination of pregabalin by an ...
ABSTRACT A simple, specific, fast and reliable liquid chromatography-tandem mass spectrometry (LC... more ABSTRACT A simple, specific, fast and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for quantification of atorvastatin (ATOR) and active metabolite of fenofibrate i.e. fenofibric acid (FENA) using simvastatin (SIMV) as IS in human plasma. Both the drugs were extracted by simple liquid-liquid extraction. The chromatographic separation was performed on a reversed-phase Phenomenex Gemini C18 column with a mobile phase of methanol – water containing 0.1% formic acid (9:1, v/v). The protonated analytes were quantified in positive ionization for ATOR &amp; SIMV (IS) and negative ionization for FENA, simultaneously by multiple reaction monitoring with a mass spectrometer. The method was validated over the concentration range of 1 to 50 ng/ml for ATOR and 25 to 4000 ng/ml FENA in human plasma. The MRM transition of m/z 559 – 440, m/z 317 – 231 and m/z 441 – 325 were used to measure ATOR, FENA and SIMV (IS) respectively. This method was successfully applied to the pharmacokinetic study of fixed dose combination (FDC) of ATOR and FENA formulation product after an oral administration to Indian healthy human volunteers.
Indian chromite ore production was 3.728 MT and ferrochrome alloy production was 1.0 MT during 20... more Indian chromite ore production was 3.728 MT and ferrochrome alloy production was 1.0 MT during 2016-17. More than 95% of it was mined from Sukinda valley in the state of Odisha. The current Sukinda chromite ore is friable in nature and generate a lot of fine material, thus more than 95% of mined ore is less than 5 mm size fraction. Agglomeration is necessary for utilizing these chromite fines before charging in a submerged arc furnace. Normal chromite agglomeration processes include briquetting, pelletizing or sintering. Presently many ferro-chrome plants make pellets utilizing the ore fines by grinding it to suitable finer size (say 60% < 45 μm) and pelletize them. However, pelletizing is only suitable for vary fine feed that requires energy intensive grinding, expensive binders, and energy-intensive induration of pellets using liquid or gaseous fuel. Overall, the pelletization process is very complex and cost-intensive. In some plants, briquetting (cold & environment friendly p...
Etude de la degradation de colorants alimentaires par des bacteries de la microflore intestinale ... more Etude de la degradation de colorants alimentaires par des bacteries de la microflore intestinale humaine. Les bacteries reduisent ces colorants azoiques et les transforment en amines. Il apparait egalement que les bacteries sont capables d'utiliser ces memes colorants comme seule source de carbone
Journal of Pharmaceutical and Biomedical Analysis, 2012
A rapid, simple, and sensitive high performance liquid chromatography-tandem mass spectrometry me... more A rapid, simple, and sensitive high performance liquid chromatography-tandem mass spectrometry method (LC-ESI-MS/MS) was developed and validated for the determination and pharmacokinetic investigation of choline (CL), active metabolite of citicoline in human plasma using metformin (MF) as IS. The chromatographic separation was performed on a reversed-phase Phenomenx Gemini C18 column with a mobile phase of methanol:water (containing 10 mM ammonium formate) (9:1, v/v). The calibration curves were linear over the range of 0.05-5 g/ml. The validated LC-ESI-MS/MS method was successfully applied for the evaluation of pharmacokinetic parameters and bioequivalence study of test and reference control release (CR) tablet preparation of citicoline 1000 mg after a single oral administration to all 12 healthy male volunteers.
A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was develo... more A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed and validated for quantification of metoprolol succinate (MPS) and amlodipine besylate (AM) using hydrochlorothiazide (HCTZ) as IS in human plasma. Both the drugs were extracted by simple liquid-liquid extraction with chloroform. The chromatographic separation was performed on a reversed-phase peerless basic C18 column with a mobile phase of methanol-water containing 0.5% formic acid (8:2, v/v). The protonated analyte was quantitated in positive ionization by multiple reaction monitoring with a mass spectrometer. The method was validated over the concentration range of 1-100 ng/ml for MPS and 1-15 ng/ml AM in human plasma. The MRM transition of m/z 268.10-103.10, m/z 409.10-334.20 and m/z 296.00-205.10 were used to measure MPS, AM and HCTZ (IS), respectively. This method was successfully applied to the pharmacokinetic study of fixed dose combination (FDC) of MPS and AM formulation product after an oral administration to Indian healthy human volunteers.
A highly sensitive liquid chromatographic-tandem mass spectrometric method (LC-MS-MS) is develope... more A highly sensitive liquid chromatographic-tandem mass spectrometric method (LC-MS-MS) is developed to quantitate ranolazine in human plasma. The analyte and internal standard tramadol are extracted from plasma by liquid-liquid extraction using diethyl ether-dichloromethane (60:40 v/v), and separated on a Zorbax extend C 18 column using methanol-10mM ammonium acetate (60:40 v/v, pH 4.0) at a flow of 1.0 mL/min. Detection is carried out by multiple reaction monitoring on a QtrapTM LC-MS-MS system with an electrospray ionization interface. The assay is linear over the range 10-5000 ng/mL with a limit of quantitation of 10 ng/mL and a lower limit of detection (S/N > 3) of 1 ng/mL. Intra-and inter-day precision are < 3.1% and < 2.8%, respectively, and the accuracy is in the range 96.7-101.6%. The validated method is successfully used to analyze the drug in samples of human plasma for pharmacokinetic studies. Experimental Chemicals and reagents Ranolazine hydrochloride (purity > 99.0%) and tramadol hydrochloride [internal standard (IS), purity > 99.
The pharmacokinetics of nitazoxanide (CAS 55981-09-4) and ofloxacin (CAS 82419-36-1) has been ext... more The pharmacokinetics of nitazoxanide (CAS 55981-09-4) and ofloxacin (CAS 82419-36-1) has been extensively evaluated in adult human volunteers individually after oral administration of tablet formulation. However, no published data is available regarding the combined pharmacokinetics and bioavailability of this particular fixed dose combination. In light of the above, a clinical study was designed to evaluate the bioequivalence of two fixed dose combination (FDC) products of two manufacturers containing nitazoxanide 500 mg and ofloxacin 200 mg in healthy Indian male volunteers. 24 healthy male volunteers (age 25 +/- 4.6 years; weight 74.5 +/- 7.87 kg) were enrolled in this study. Each subject received a Test fixed dose combination and a Reference fixed dose combination formulation in a randomized, single dose, fasting state, two period, crossover study design with a 1-week washout period between the doses. Extraction of the drugs from the plasma was carried out by precipitation method. Analysis of tizoxanide (active metabolite of nitazoxanide) and ofloxacin from plasma samples was done by a simple and sensitive HPLC method using UV detection developed in our laboratory. An analysis of variance was performed on the pharmacokinetic parameters Cmax, AUC(0-t), AUC(0-infinity). using general linear model (GLM) procedures in which sources of variation were subject, formulation, period. The results of this investigation indicated that there were no statistically significant differences between the two products in either the mean concentration-time profiles or in the obtained pharmacokinetic parameters. 90 % confidence limits for the log-transformed data of Cmax, AUC(0-t), AUC(0-infinity) were within the acceptable range of 0.80-1.25. Thus, these findings clearly indicate that the two products are bioequivalent in terms of rate and extent of drug absorption. Both the preparations were well tolerated with no adverse reactions seen throughout the study.
Lovastatin is a lipid-lowering agent indicated for primary hypercholesterolemia. This study has a... more Lovastatin is a lipid-lowering agent indicated for primary hypercholesterolemia. This study has assessed single-dosing pharmacokinetics of lovastatin and of its main metabolite, lovastatin beta-hydroxyacid, and has compared the pharmacokinetics of two formulations of lovastatin, a test lovastatin generic (LVSG), and a reference (mevinacor 40 MSD) preparation. The pharmacokinetics and bioequivalence of the two formulations of lovastatin were evaluated by a two-way cross-over randomized double blinded study, in 36 healthy volunteers after a single oral dose of 2 x 40 mg per subject. On plasma samples, collected at given intervals of time (0-24h), lovastatin and its main active metabolite were assayed by high pressure liquid chromatography with positive turbo ion spray ionization tandem mass spectrometry detection. The pharmacokinetic parameters, area under the curve total (AUC(t)) and to infinity (AUC(inf)), peak plasma concentration (C(max)), time to attain peak (t(max)), and elimination half-life (t(1/2)) were determined and analyzed statistically. Only minor differences in the pharmacokinetics of lovastatin and lovastatin hydroxyacid between LVSG and mevinacor were found. Analysis of variance (ANOVA) did not show any significant difference between the two formulations, and 90% confidence intervals fell within the acceptable range for bioequivalence. The tolerability profile was good and comparable for the two formulations of lovastatin. Our study, which was performed with the largest number of subjects compared with those published in literature, indicates the bioequivalence of LVSG and mevinacor tablets. The high inter-subject variability of parameters investigated indicate the need of appropriate sample size in pharmacokinetics studies with lovastatin.
A sensitive and selective liquid chromatographic tandem mass spectrometric (LCMSMS) method was ... more A sensitive and selective liquid chromatographic tandem mass spectrometric (LCMSMS) method was developed for simultaneous identification and quantification of tamsulosin and dutasteride in human plasma, which was well applied to clinical study. The method was based on ...
A bioanalytical method has been developed and validated for determination of pregabalin in human ... more A bioanalytical method has been developed and validated for determination of pregabalin in human plasma. The analytical method consists in the precipitation of plasma sample with trichloro acetic acid (20% v/v solution in water), followed by the determination of pregabalin by an ...
ABSTRACT A simple, specific, fast and reliable liquid chromatography-tandem mass spectrometry (LC... more ABSTRACT A simple, specific, fast and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for quantification of atorvastatin (ATOR) and active metabolite of fenofibrate i.e. fenofibric acid (FENA) using simvastatin (SIMV) as IS in human plasma. Both the drugs were extracted by simple liquid-liquid extraction. The chromatographic separation was performed on a reversed-phase Phenomenex Gemini C18 column with a mobile phase of methanol – water containing 0.1% formic acid (9:1, v/v). The protonated analytes were quantified in positive ionization for ATOR &amp; SIMV (IS) and negative ionization for FENA, simultaneously by multiple reaction monitoring with a mass spectrometer. The method was validated over the concentration range of 1 to 50 ng/ml for ATOR and 25 to 4000 ng/ml FENA in human plasma. The MRM transition of m/z 559 – 440, m/z 317 – 231 and m/z 441 – 325 were used to measure ATOR, FENA and SIMV (IS) respectively. This method was successfully applied to the pharmacokinetic study of fixed dose combination (FDC) of ATOR and FENA formulation product after an oral administration to Indian healthy human volunteers.
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Papers by Debotri Ghosh