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Bihola U, Prajapati P, Agrawal YK. HPLC – Quality by Design Approach for Simultaneous Detection of Torsemide, Spironolactone and Their Degradant Impurities. Pharmaceutical Technology in Hospital Pharmacy 2018. [DOI: 10.1515/pthp-2018-0011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
A simple, highly robust (quality by design (QbD) approach), precise and accurate method using high performance liquid chromatography coupled to mass spectrometry has been established for the simultaneous separation, identification and quantitation of a Torsemide (TOR), spironolactone (SPI) and their degradant impurities. The chromatographic separations of drugs and impurities were achieved on a inertsil ODS-3 µm C18, 150 mm × 4.6 mm, while the isocratic elution using a ternary mobile phase mixture of methanol, acetonitrile and water (5:3:2 v/v/v) at a flow rate of 0.2 mL/min was adopted for achieving optimum separations. The quantitation of torsemide and spironolactone was accomplished by UV detection at 254 nm and identification of the degradants were done by comparing identical mass in mass spectrometer. The recoveries of the torsemide and spironolactone were obtained higher than 98 % with good validation parameters; linearity (r2>0.994), LOD and LOQ was 10 and 33 ng for TOR and 75 and 248 ng for SPI respectively. The quality by design (QbD) approach has been successfully utilized to prove the method is robust even deliberate changes in critical parameters.
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Affiliation(s)
- Unnati Bihola
- Institute of Research and Development , Gujarat Forensic Sciences University , Sector-9, Nr. Police bhavan , Gandhinagar 382007 , Gujarat , India
| | - Prajesh Prajapati
- Institute of Research and Development , Gujarat Forensic Sciences University , Sector-9, Nr. Police bhavan , Gandhinagar 382007 , Gujarat , India
| | - Y. K. Agrawal
- Institute of Research and Development , Gujarat Forensic Sciences University , Sector-9, Nr. Police bhavan , Gandhinagar 382007 , Gujarat , India
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Agrawal YK, Tandon SG. On the Ratio of Successive Stepwise Complex Formation Constants: Metal Complexes of N-Phenyl-Meta-Methyl- Benzohydroxamic Acid. Z PHYS CHEM 2017. [DOI: 10.1515/zpch-1974-25577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Budhraja RH, Shah MA, Suthar M, Yadav A, Shah SP, Kale P, Asvadi P, Valan Arasu M, Al-Dhabi NA, Park CG, Kim YO, Kim HJ, Agrawal YK, Krovidi RK. LC-MS/MS Validation Analysis of Trastuzumab Using dSIL Approach for Evaluating Pharmacokinetics. Molecules 2016; 21:molecules21111464. [PMID: 27827861 PMCID: PMC6274275 DOI: 10.3390/molecules21111464] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 10/25/2016] [Accepted: 10/26/2016] [Indexed: 11/16/2022] Open
Abstract
Quantitative targeted proteomics based approaches deploy state-of-the-art Liquid chromatography tandem mass spectrometry LC-MS technologies and are evolving as a complementary technique to standard ligand-binding based assays. Advancements in MS technology, which have augmented the specificity, selectivity and sensitivity limits of detection and freedom from antibody generation, have made it amicable towards various clinical applications. In our current work, a surrogate peptide based quantitative proteomics assessment is performed by selecting specific signature peptides from the complementary determining region CDR region of trastuzumab (Herclon®, Roche products in India). We developed a double Stable Isotope Label (dSIL) approach by using two different surrogate peptides to evaluate the proteolytic digestion efficiency and accurate quantification of the target analyte peptide of Herclon® in human serum. Method validation experiments were meticulously performed as per bioanalytical method validation guidelines. The dSIL approach, using an LC-MS/MS based quantification assay demonstrated good linearity over a range of 5-500 µg/mL of Herclon®, and validation experimental data is in compliance with bioanalytical regulatory guidelines.
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Affiliation(s)
- Rohit H Budhraja
- Panomics Lambda Therapeutic Research Limited, Gota, Ahmedabad, Gujarat 382481, India.
| | - Milin A Shah
- Panomics Lambda Therapeutic Research Limited, Gota, Ahmedabad, Gujarat 382481, India.
| | - Mahendra Suthar
- Panomics Lambda Therapeutic Research Limited, Gota, Ahmedabad, Gujarat 382481, India.
| | - Arun Yadav
- Panomics Lambda Therapeutic Research Limited, Gota, Ahmedabad, Gujarat 382481, India.
| | - Sahil P Shah
- Panomics Lambda Therapeutic Research Limited, Gota, Ahmedabad, Gujarat 382481, India.
| | - Prashant Kale
- Panomics Lambda Therapeutic Research Limited, Gota, Ahmedabad, Gujarat 382481, India.
- Department of Pharmaceutical Sciences, Gujarat Forensic Sciences University, Gandhinagar 382481, India.
| | - Parisa Asvadi
- Analytical Development and Global Regulatory Affairs, Intas Pharmaceuticals Ltd., Ahmedabad, Gujarat 382213, India.
| | - Mariadhas Valan Arasu
- Department of Botany and Microbiology, Addiriyah Chair for Environmental Studies, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
| | - Naif Abdullah Al-Dhabi
- Department of Botany and Microbiology, Addiriyah Chair for Environmental Studies, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
| | - Chun Geon Park
- Department of Medicinal Crop Research, Rural Development Administration, Eumseong, Chungbuk 369-873, Korea.
| | - Young-Ock Kim
- Department of Medicinal Crop Research, Rural Development Administration, Eumseong, Chungbuk 369-873, Korea.
| | - Hak Jae Kim
- Department of Clinical Pharmacology, College of Medicine, Soonchunhyang University, Cheonan 31151, Korea.
| | - Y K Agrawal
- Department of Pharmaceutical Sciences, Gujarat Forensic Sciences University, Gandhinagar 382481, India.
| | - Ravi K Krovidi
- Panomics Lambda Therapeutic Research Limited, Gota, Ahmedabad, Gujarat 382481, India.
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Abstract
The hydroxamic acids are useful chelating agents for inorganic and organic analysis. For their rational application the data on dissociation constants are desirable. In the present communication the thermodynamic dissociation constants of several hydroxamic acids have been determined at 25°C. The calculation method is described earlier1.
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Affiliation(s)
- Y. K. Agrawal
- Department of Chemistry, Govt. Polytechnic Ujjain (M. P.), India
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Jamal S, Agrawal YK. Labeling of nucleosides with fluorescamine and detection by spectrofluorometer for End Stage Renal Disease. Saudi J Biol Sci 2013; 20:327-31. [PMID: 24235868 DOI: 10.1016/j.sjbs.2013.02.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 02/16/2013] [Indexed: 11/17/2022] Open
Abstract
Nucleosides are characterized as biomarkers in AIDS, Alzheimer, tumor, breast cancer and various malignant diseases. In the present work a direct method for the detection of nucleosides (adenosine, cytidine, uridine and guanosine) from urine samples has been developed. Nucleosides represent the extent of damage in genetic material, analysis of nucleosides by ultrasonic assisted microextraction effectively eliminates the interfering constituent of urine. This has made it a highly selective and sensitive method to analyze the nucleosides with a lower limit of detection 0.220 μmol/L and Limit of quantitation 0.660 μmol/L. The method has been validated with good linearity and correlation of coefficients of the calibration curves was higher than 0.997. The coefficients were in the range of 0.11-16.92% (inter-day) and 0.38-16.43% (intra-day), respectively.
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Affiliation(s)
- Shubi Jamal
- Institute of Research & Development, Gujarat Forensic Science University, Gandhinagar, Sector 18A, Near Police Bhavan, Gujarat 382007, India
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Shah M, Agrawal YK, Garala K, Ramkishan A. Solid lipid nanoparticles of a water soluble drug, ciprofloxacin hydrochloride. Indian J Pharm Sci 2013; 74:434-42. [PMID: 23716872 PMCID: PMC3660870 DOI: 10.4103/0250-474x.108419] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2011] [Revised: 10/24/2012] [Accepted: 10/26/2012] [Indexed: 11/25/2022] Open
Abstract
The aim of this study was to understand and investigate the relationship between experimental factors and their responses in the preparation of ciprofloxacin hydrochloride based solid lipid nanoparticles. A quadratic relationship was studied by developing central composite rotatable design. Amount of lipid and drug, stirring speed and stirring time were selected as experimental factors while particle size, zeta potential and drug entrapment were used as responses. Prior to the experimental design, a qualitative prescreening study was performed to check the effect of various solid lipids and their combinations. Results showed that changing the amount of lipid, stirring speed and stirring time had a noticeable influence on the entrapment efficiencies and particle size of the prepared solid lipid nanoparticles. The particle size of a solid lipid nanoparticle was in the range of 159-246 nm and drug encapsulation efficiencies were marginally improved by choosing a binary mixture of physically incompatible solid lipids. Release of ciprofloxacin hydrochloride from solid lipid nanoparticle was considerably slow, and it shows Higuchi matrix model as the best fitted model. Study of solid lipid nanoparticle suggested that the lipid based carrier system could potentially be exploited as a delivery system with improved drug entrapment efficiency and controlled drug release for water soluble actives.
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Affiliation(s)
- M Shah
- Gujarat Forensic Sciences University, Institute of Research and Development, Near Police Bhavan, Sector 18A, Gandhinagar-382 007, India
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Abstract
One of the major problems associated with poorly soluble drugs is very low bioavailability. The problem is even more complex for drugs like itraconazole, simvastatin, and carbamazepine which are poorly soluble in both aqueous and nonaqueous media, belonging to BCS class II as classified by biopharmaceutical classification system. Formulation as nanosuspension is an attractive and promising alternative to solve these problems. Nanosuspension consists of the pure poorly water-soluble drug without any matrix material suspended in dispersion. Preparation of nanosuspension is simple and applicable to all drugs which are water insoluble. A nanosuspension not only solves the problems of poor solubility and bioavailability, but also alters the pharmacokinetics of drug and thus improves drug safety and efficacy. This review article describes the preparation methods, characterization, and applications of the nanosuspension.
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Affiliation(s)
- Vishal R Patel
- Institute of Research and Development, Gujarat Forensic Sciences University, Sector 18/A, B/H Police Bhavan, Gandhinagar, Gujarat, India
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Shah RY, Agrawal YK. Introduction to fiber optics: Sensors for biomedical applications. Indian J Pharm Sci 2012; 73:17-22. [PMID: 22131617 PMCID: PMC3224405 DOI: 10.4103/0250-474x.89752] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 01/12/2011] [Accepted: 01/18/2011] [Indexed: 11/29/2022] Open
Abstract
The paper focuses on the introduction of fiber optics, a fusion of science and engineering and describes the materials generally used for its construction along with the procedure used to design the fibers. It gives an idea of the materials used for the construction along with the pros and cons associated with them and various factors governing the emission of ultraviolet, infrared or visible radiations. The central core revolves around the applications of optical fibers in the medical and biomedical field and extending the use of the same in pharmaceutical industry as probes in quality control and dosage form analysis.
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Affiliation(s)
- R Y Shah
- Department of Pharmaceutical Analysis, Institute of Research and Development, Gujarat Forensic Sciences University, Gandhinagar - 382 007, India
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Agrawal YK, Gogoi PJ, Manna K, Bhatt HG, Jain VK. A supercritical fluid chromatography/tandem mass spectrometry method for the simultaneous quantification of metformin and gliclazide in human plasma. Indian J Pharm Sci 2011; 72:50-7. [PMID: 20582190 PMCID: PMC2883227 DOI: 10.4103/0250-474x.62231] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 10/05/2009] [Accepted: 12/23/2009] [Indexed: 11/17/2022] Open
Abstract
Present study reports the development and validation of a simultaneous estimation of metformin and gliclazide in human plasma using supercritical fluid chromatography followed by tandem mass spectrometry. Acetonitrile:water (80:20) mixture was used as a mobile phase along with liquid CO2 in supercritical fluid chromatography and phenformin as an internal standard. The modified plasma samples were analyzed by electro-spray ionization method in selective reaction monitoring mode in tandem mass spectrometry. Supercritical fluid chromatographic separation was performed using nucleosil C18 containing column as a stationary phase. The separated products were identified by characteristic peaks and specific fragments peaks in tandem mass spectrometry as m/z 130 to 86 for metformin, m/z 324 to 110 for gliclazide and m/z 206 to 105 for phenformin. The present method was found linear in the concentration ranges of 6.0-3550 ng/ml and 7.5-7500 ng/ml for metformin and gliclazide, respectively. Pharmacokinetic study was performed after an oral administration of dispersible tablets containing 500 mg of metformin and 80 mg of gliclazide using same techniques.
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Affiliation(s)
- Y K Agrawal
- Institute of Research & Development, Gujarat Forensic Sciences University, Gandhinagar-382 007, India
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Bhatt HG, Agrawal YK, Raval HG, Manna K, Desai PR. Histamine H4 receptor: a novel therapeutic target for immune and allergic responses. Mini Rev Med Chem 2011; 10:1293-308. [PMID: 21175423 DOI: 10.2174/138955710793564124] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 07/17/2010] [Indexed: 11/22/2022]
Abstract
HIstamine is a biomolecular compound located in various parts of body. It participated in various important cellular activities associated with allergy and asthma. This magic bio-molecule is directly and indirectly involved in various biochemical reactions through G-protein couple receptors. Various histamine receptors and their unexplored biochemical activities attracted many biologists in last few decades. A surprising discovery of histamine H(4) receptor was done when scientist worked on histamine H(3) receptor in brain cells. The binding pocket of histamine H(4) differs by transmembrane domains (TM3, TM5 and TM6) from histamine H(3)-sub type. In this review, we enlightened various functions of histamine H(4) and use of histamine H(4) receptor antagonists in autoimmune diseases, allergic responses, inflammatory responses, and in superoxide generation which are helpful to establish H(4) receptor antagonists as newer anti histamines.
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Affiliation(s)
- H G Bhatt
- Institute of Pharmacy, Nirma University, S. G. Highway, Chharodi, Ahmedabad-382 481. India.
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Affiliation(s)
- B. R. Pandya
- a Chemistry Department , School of Sciences, Gujarat University , Ahmedabad, 380 009, India
| | - S. K. Menon
- a Chemistry Department , School of Sciences, Gujarat University , Ahmedabad, 380 009, India
| | - Y. K. Agrawal
- a Chemistry Department , School of Sciences, Gujarat University , Ahmedabad, 380 009, India
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Abstract
Packaging is the coordinated system that encloses and protects the dosage form. Counterfeit drugs are the major cause of morbidity, mortality, and failure of public interest in the healthcare system. High price and well-known brands make the pharma market most vulnerable, which accounts for top priority cardiovascular, obesity, and antihyperlipidemic drugs and drugs like sildenafil. Packaging includes overt and covert technologies like barcodes, holograms, sealing tapes, and radio frequency identification devices to preserve the integrity of the pharmaceutical product. But till date all the available techniques are synthetic and although provide considerable protection against counterfeiting, have certain limitations which can be overcome by the application of natural approaches and utilization of the principles of nanotechnology.
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Affiliation(s)
- Ruchir Y. Shah
- Institute of Research and Development, Gujarat Forensic Sciences University, B/H Police Bhavan, Gandhinagar, Gujarat, India
| | - Prajesh N. Prajapati
- Institute of Research and Development, Gujarat Forensic Sciences University, B/H Police Bhavan, Gandhinagar, Gujarat, India
| | - Y. K. Agrawal
- Institute of Research and Development, Gujarat Forensic Sciences University, B/H Police Bhavan, Gandhinagar, Gujarat, India
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Affiliation(s)
- Y. K. Agrawal
- a Analytical Laboratory, Institute of Pharmacy and Faculty of Science, Nirma University of Science and Technology , Ahmedabad, India
| | - J. P. Pancholi
- a Analytical Laboratory, Institute of Pharmacy and Faculty of Science, Nirma University of Science and Technology , Ahmedabad, India
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Agrawal YK, Thaker DN. Environmentally Benign Syntheses of Calixarene Derivatives. SYNTHETIC COMMUN 2008. [DOI: 10.1080/00397910802138959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Y. K. Agrawal
- a Analytical Laboratory, Institute of Pharmacy and Faculty of Science, Nirma University of Science and Technology , Ahmedabad, India
| | - D. N. Thaker
- a Analytical Laboratory, Institute of Pharmacy and Faculty of Science, Nirma University of Science and Technology , Ahmedabad, India
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Agrawal YK, Raj KPS, Desai SJ, Patel SG, Merh SS. Effect of lead from motor‐vehicle exhausts on plant and soil along a major thoroughfare in Baroda city. ACTA ACUST UNITED AC 2008. [DOI: 10.1080/00207238008737411] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Abstract
To develop the newer pharmaceuticals and to spur the strong growth, being a general property of 'handedness', chirality plays a major role. The Easson-Stedman principle shows the differences in the biological activity between enantiomers resulted from selective reactivity of one enantiomer with its receptor. It helps to improve the pharmacokinetic properties and to remove undesirable side effects by virtue of the unique activity of enantiomers. Racemic switching and marketing drug combinations are used as tools for drug life-cycle management and to redevelop racemic mixtures as single enantiomers.
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Affiliation(s)
- Y K Agrawal
- Institute of Pharmacy, NIRMA University, S. G. Highway, Chharodi, Ahmedabad - 382 481, India.
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Affiliation(s)
- Y. K. Agrawal
- a Institute of Pharmacy, Nirma University of Science and Technology , Ahmedabad, India
| | - N. C. Desai
- b Department of Chemistry , Bhavnagar University , Bhavnagar, India
| | - N. D. Mehta
- b Department of Chemistry , Bhavnagar University , Bhavnagar, India
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Shah AK, Agrawal YK, Banerjee SK. Spectrophotometric Determination of Thiacetazone. ANAL LETT 2007. [DOI: 10.1080/00032718108081412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Agrawal YK, Patel MP, Merh SS. Lead in soils and plants: its relationship to traffic volume and proximity to highway (Lalbag, Baroda city). ACTA ACUST UNITED AC 2007. [DOI: 10.1080/00207238108709873] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Jain VK, Pandya RA, Pillai SG, Agrawal YK, Kanaiya PH. Solid-phase extractive preconcentration and separation of lanthanum(III) and cerium(III) using a polymer-supported chelating calix [4] arene resin. J Anal Chem 2007. [DOI: 10.1134/s1061934807020025] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Agrawal YK, Vaidya H, Bhatt H, Manna K, Brahmkshatriya P. Recent advances in the treatment of thromboembolic diseases: Venous thromboembolism. Med Res Rev 2007; 27:891-914. [PMID: 17318813 DOI: 10.1002/med.20100] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Venous thromboembolic diseases are the major concern of rising cost of healthcare and are commonest health problem across the globe. Both genetic and acquired risk factors are believed to be strongly linked with these diseases. Commonly encountered problems to the therapy include dose fixing and routine monitoring, yet some serious problems of bleeding also necessitate the immediate need to develop new agents. The review is primarily concerned with the new developments in the treatment of thromboembolic diseases. Therapeutic applications of anticoagulants, antiplatelets, and thrombolytics have been discussed in enough detail.
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Affiliation(s)
- Y K Agrawal
- Institute of Pharmacy, Nirma University of Science and Technology, Sarkhej-Gandhinagar Highway, Ahmedabad 382481, Gujarat, India.
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Rastogi RP, Srivastava RC, Agrawal YK. Dynamic instability at liquid/vapor interface far from equilibrium. J Colloid Interface Sci 2006; 297:711-4. [PMID: 16338233 DOI: 10.1016/j.jcis.2005.10.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2005] [Revised: 10/18/2005] [Accepted: 10/29/2005] [Indexed: 10/25/2022]
Abstract
Attempt has been made to elucidate the mechanism of electric potential oscillations at oil-aqueous solution interface involving adsorption at oil-vapor interface on a semi-theoretical basis. The mechanism stipulates adsorption of ammonia, amines and pheromones at the liquid-vapor interface followed by transfer of ions through membrane-aqueous solution interface and subsequent interaction of ammonium (amine) ions and carbocations from pheromones with diffusing halide ions from the bulk. Relationship of the above mechanism with sensing mechanism of smell by olfactory nerves has also been pointed out.
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Affiliation(s)
- R P Rastogi
- Chemistry Department, Gorakhpur University, Gorakhpur 273 009, India.
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Jain VK, Pandya RA, Pillai SG, Shrivastav PS, Agrawal YK. Merrifield Resin Supported Chelate Forming Calix[4]arene‐o‐vanillinthiosemicarbazone Resin Employed for the Separation, Preconcentration and Trace Determination of Cr(VI), As(III) and Tl(I) in Water Samples. SEP SCI TECHNOL 2006. [DOI: 10.1080/01496390500445626] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Agrawal YK, Patel RN. Chiral chromatographic separation of beta-blockers. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 820:23-31. [PMID: 15866489 DOI: 10.1016/j.jchromb.2005.03.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2004] [Revised: 02/12/2005] [Accepted: 03/01/2005] [Indexed: 11/20/2022]
Abstract
A novel amide based chiral stationary phase m-[(+)-alpha-methyl benzyl carboxamide] XAD-4 has been synthesized by covalently linking R(+)-1-phenylethylamine to chloroformoyl Amberlite XAD-4 under weak alkaline conditions. The synthesized resin has been primarily characterized by m.p., elemental analysis and FT-IR and 13C NMR spectra. beta-Blockers viz. atenolol, metoprolol, and propranolol were successfully separated into their enantiomers using a mixture of sodium acetate-acetic acid buffer (pH 4.1):acetonitrile (4:6, v/v) solution using the synthesized resin. Hydrogen bonding and pi-pi interactions are supposed to be the major analyte-chiral stationary phase interactions.
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Affiliation(s)
- Y K Agrawal
- Institute of Pharmacy, Nirma University of Science and Technology, Sarkhej-Gandhinagar Highway, Ahmedabad, Gujarat 382 481, India.
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Patel G, Agrawal YK. Separation and trace estimation of benzidine and its macromolecular adducts using supercritical fluid chromatography. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 795:157-65. [PMID: 14522020 DOI: 10.1016/s1570-0232(03)00558-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A sensitive, rapid, selective and reproducible method has been developed to measure blood plasma levels of benzidine (BZ) and its acetylated metabolite, N-OH-N,N'-diacetylbenzidine (N-OH-DABZ), using supercritical fluid chromatography (SFC) for the first time. Benzidine and N-OH-N,N'-diacetylbenzidine were extracted from the plasma using ether. Separation was done on a Nucleosil (250 mm x 4.6 mm) 10 microm, Nucleosil-RP-C18 column with 7.4% (v/v) methanol-modified supercritical fluid carbon dioxide (2.5 ml min(-1)) as mobile phase. The column temperature was 45 degrees C and the outlet pressure was set at 8.83 MPa. The detection was done using a UV-Vis detector set at 280 nm. The limit of quantification was 0.10 ng ml(-1) (BZ) and 0.14 ng ml(-1) (N-OH-diacetylbenzidine) using 1 ml plasma specimen. The mean extraction recovery of BZ was found to be 98.6%. The SFC method was directly compared to a published HPLC-UV method. With respect to speed, organic solvent usage, sensitivity, specificity and accuracy, SFC was found to be superior. The method has been successfully used to estimate the BZ, N-OH-diacetylbenzidine levels in blood plasma of the animals who were administered 15 microg kg(-1) body weight of benzidine.Further, this method has been also applied for the detection and quantification of benzidine DNA and hemoglobin adducts from the blood and tissue samples of the benzidine dosed animals.
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Affiliation(s)
- Gauri Patel
- Department of Biochemistry, School of Sciences, Gujarat University, Ahmedabad, Gujarat 380009, India
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Girdhar R, Jain VK, Menon SK, Agrawal YK. Spectrophotometric determination of sulphacetamide. Boll Chim Farm 2002; 141:311-4. [PMID: 12426820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
A new rapid selective spectrophotometric method for the determination of sulphacetamide is described. The drug forms a orange-yellow colored complex with Cerium(IV) in sulfuric acid media which is extracted into ethyl acetate. The complex exhibits a maximum absorbance at 440 nm with a molar absorptivity of 3 x 10(2) 1 mol-1 cm-1. The system obeys Beer's law in the concentration range of 0.07-1.1 mg of sulphacetamide. The various parameters for the optimum extraction conditions are discussed. The method is applied to the determination of sulphacetamide in dosage forms.
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Affiliation(s)
- R Girdhar
- Pharmacy Department, Faculty of Technology, M.S. University of Baroda, India
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Raghavan TNV, Agrawal YK. Analysis of Trace Metals in Petroleum Crudes. 1. Trace Analysis of Vanadium and Titanium in Crude Petroleum of North Gujarat. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/i360070a014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Jagadheesan K, Agrawal YK, Sinha VK, Nizamie SH. Agranulocytosis during clozapine therapy. Indian J Psychiatry 2000; 42:447-9. [PMID: 21407991 PMCID: PMC2962756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- K Jagadheesan
- K. JAGADHEESAN, MD., Junior Resident, Central Institute of Psychiatry, Kanke (PO), Ranchi-834 006
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Agrawal YK, Majumdar F. Effect of binders on anti hypertensive drugs. Boll Chim Farm 1999; 138:531-43. [PMID: 10765470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Tablets of antihypertensive drugs, Indapamide, Methyldopa and Clonidine have been prepared and their physico-chemical properties were determined. The effect of various binders viz. starch, acacia, sodium carboxymethyl cellulose (sod. CMC), gelatin and lactose on the properties of these tablets were studied. Formulations of tablets of indapamide, methyldopa and clonidine prepared in combination with acacia, lactose and sod. CMC, respectively result in the best flow properties, minimum percentage fines, low angle of repose and compressibility. The tablets prepared from these granules possess all quality features including a good dissolution profile. Gelatin, sod. CMC and starch have less effective granule formation leading to poor quality of tablets in case of Indapamide, Methyldopa and Clonidine, respectively.
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Affiliation(s)
- Y K Agrawal
- Chemistry Department, School of Sciences Ahmedabad, India
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Agrawal YK, Menon SK, Majumudar F, Jain VK. Thermodynamic ionization constants of antihypertensive drugs. Boll Chim Farm 1999; 138:253-8. [PMID: 10464974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The thermodynamic ionization constants (pKa) of indapamide, clonidine and methyldopa have been determined at 25 degrees C and 35 degrees C by pH titration technique. The pKa varies linearly with mole fraction of dioxane. The thermodynamic parameters have been calculated.
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Affiliation(s)
- Y K Agrawal
- Department of Chemistry, School of Sciences, Gujarat University, Ahmedabad, India
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Jain VK, Sait SS, Shrivastav P, Agrawal YK. Sequential Separation and Trace Enrichment of Thorium(IV) and Uranium(VI) on Chelating Resin Amberlite XAD-2-ortho-vanillinthiosemicarbazone (o-VTSC). SEP SCI TECHNOL 1998. [DOI: 10.1080/01496399808545906] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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