Download or read book Evaluation and Application of Stationary Phase Selectivity for Drug Analysis written by Raigamage Wimal H. Perera and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite the wide range of HPLC stationary phases available for reversed-phase high-performance liquid chromatography (RP-HPLC) and the in-depth studies using probes to highlight differences between them, there is very little in the way of stationary phases which offer selectivity that is substantially different from that offered by the very commonly used alkyl-silicas. Therefore, the primary aim of the research programme was to explore and try to exploit LC stationary phases which offered genuinely different selectivity to alkyl-silicas for typical drug applications. Chiral stationary phases (CSP) potentially had different selectivity and in this context a secondary aim was to explore aspects of the enantioselectivity of CSP as well as their chemical selectivity. Claims of orthogonal selectivity had been made for pentafluorophenyl (PFP) phases and phases exhibiting the hydrophilic interaction liquid chromatography (HILlC) mode. However, the Ultra PFP phase was found to be very similar in selectivity to ACE 5 C18 for both amitriptyline and acemetacin related compounds. The ZIC-HILlC phase was shown to behave as a reversed-phase material at high aqueous content in the mobile phase. There was some indication of selectivity orthogonal to that of ACE 5 C18 with low aqueous content in the mobile phase but this occurred at low retention and with mobile phases unsuitable for use with C18 phases in coupled (column or phase) systems. Nonetheless the work carried out shed more light on the mechanisms taking place in the HILlC mode which is currently attracting so much interest. Also it was possible to put ZIC-HILlC to good use for polar plant metabolites and other applications. Chiral stationary phases (CSP) also offered the prospect of selectivity orthogonal to that of C18 phases. Given the proliferation of such phases though and the fact that it would be useful to use CSP that gave chiral separations for a broad spectrum of compound classes as well as giving orthogonal separations between different compounds, it was decided to carry out comparative studies of CSP classes in order to identify any redundancies and to seek out CSP that were complementary to one another. The Regis Whelk-01 CSP was shown to be much superior to other higher-generation Pirkle-concept CSP such as DACH-DNB and ULMO. Also it was shown to be complementary to the Chiralcel OD derivatised polysaccharide CSP and that both had something to offer alongside the widely used Chiralpak AD derivatised polysaccharide CSP. It was also found that a series of Chiralcel OD clones were virtually identical to Chiralcel OD and similarly for Chiralpak AD clones. Chiralpak lA, an immobilised version of Chiralpak AD, was not markedly less enantioselective than Chiralpak AD. Chiralcel OJ was less enantioselective than Chiralpak AD but the gap in performance was not as wide as between Whelk-01 and the other Pirkle-concept CSP. The information gathered during these studies should prove to be of enormous value for further work in chiral LC method development screening. Before embarking on applications work utilising the stationary phase selectivity that had been found, a study was carried out on the effectiveness of the high efficiencies obtainable with short run times through ultra-performance liquid chromatography (UPLC). It was found that, for a range of pharmaceutical applications, that it was still necessary in each case to adjust selectivity before increasing speed through working at higher temperatures with faster flow rates. In the course of this work some exceptionally high speed separations for example for paroxetine and related substances, benzodiazepines and flurbiprofen and related substances, were developed. With respect to the evaluation of CSP as orthogonal phases to alkyl silicas under reversed-phase conditions, the Whelk-01 CSP showed promise. However on closer inspection it was found that the Whelk-01 CSP had very similar selectivity to the alkyl silica phase, ACE 5 C18, and deviation from this only occurred in instances when there was interaction with the chiral recognition site to give a separation of enantiomers. This prompted the notion that, rather than using Whelk- 01 in a coupled column system with ACE 5 C18, it could be used on its own for the separation of both trace enantiomer and all other related substances. This was shown to be possible using (S)-naproxen, laevokalim and (S)-flurbiprofen as illustrative examples. The evaluation of the enantioselectivity of CSP led to an optimised resolution (suitable for scaling up for preparative work) of the enantiomers of the former 'legal-high' drug, mephedrone, on Whelk-01 under normal phase conditions. It was also shown that the infrequently used Chiralcel OJ derivatised polysaccharide CSP was ideal for developing an assay to determine trace amounts of (R)-nicotine in (S)-nicotine. Overall, the information obtained on stationary phase selectivity and retentivity through evaluation and application will be of great value in HPLC and UHPLC column selection and also selection of orthogonal phases for coupled column systems but, ultimately, moving forward, most value may be in aiding the design of two-dimensional LC systems for complex mixture analysis. This would particularly apply to the use of CSP with reversed-phase eluents in achiral-chiral systems.
Download or read book Synthesis and Evaluation of Four Novel Stationary Phases in High Pressure Liquid Chromatography written by Niloofar Salehi and published by . This book was released on 2012 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: High pressure liquid chromatography is one of the most frequently used methods for the separation of mixtures. Chemically modified silica hydride stationary phases, due to their unique selectivity and versatility, have been the focus of an increasing number of studies in the past several years. The objective of fabricating stationary phases with dual properties is to achieve separation of both polar and non-polar components in a single analysis. Due to an increasing demand in the fields of drug discovery, proteomics, and metabolomics to analyze numerous samples with a wide range of polarities, there is a need for more versatile stationary phases for a wide range of applications. In order to meet the above objective, in this research four novel silica hydride-based columns were synthesized using a hydrosilation procedure. The characterization of each column was done using a series of polar and nonpolar compounds by studying their aqueous normal phase and reversed-phase chromatographic behavior. Under these conditions, it turned out that two columns showed both RP and ANP behaviors. Of the remaining columns, one exhibited ANP behavior only and the other performed only in the reversed-phase mode.
Download or read book Chiral Liquid Chromatography written by w Lough and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: While working as a chromatographer in the pharmaceutical industry, it became apparent to the editor that there was a pressing need for a comprehensive reference text for analysts working on the resolution of enantiomers by liquid chromatography (LC). This need arises from the fact that, whereas previously it was very difficult to determine enantiomers by direct means, there is now a wide choice of direct LC methods. At the same time, regulatory authorities have been changing their attitudes towards the administration of pharmaceuticals as racemates, partly because it is now possible to study the individual enantiomers. Clearly this abundance of new information needs to be rationalized. More importantly, the chiral LC systems which are commercially available or readily accessible to the practising chromatographer needed to be reviewed and, to a much greater extent than in existing reviews or books, discussed in terms of their practical application. Accordingly this book is very much orientated towards the practical aspects of these commercially available and readily accessible chiral LC systems. To this end, it is written for practising chromatographers by a team of practising, experienced chromatographers who have spent many years tackling the problems presented by resolving enantiomers by LC. The practical aspects of common chiral LC systems cannot be fully understood if discussed in isolation.
Download or read book Supercritical Fluid Chromatography written by Gregory K. Webster and published by CRC Press. This book was released on 2014-02-04 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Analytical chemists in the pharmaceutical industry are always looking for more-efficient techniques to meet the analytical challenges of today’s pharmaceutical industry. One technique that has made steady advances in pharmaceutical analysis is supercritical fluid chromatography (SFC). SFC is meeting the chromatography needs of the industry by providing efficient and selective testing capabilities on the analytical and preparative scale. The supercritical fluid mobile phase, consisting mainly of CO2, facilitates cost reduction costs and helps the industry in meeting green chemistry standards. This book provides a comprehensive overview of the use of SFC in pharmaceutical analysis. Supercritical Fluid Chromatography reviews the use of SFC in drug-discovery applications and describes its application in drug development. When a drug is developed and brought to market, it is tested many times for impurities and degradants, enantiomeric purity, and analytical and preparative isolations—it is tested during discovery and development and for under-regulated and unregulated methodologies. The book describes the use of SFC for each of these applications and discusses more in-depth topics, such as the use of SFC in mass spectrometric and polarographic detection. The book also sheds light on the role of SFC in drug development from natural products and the advancement of SFC with new technologies and its use in pilot-scale operations as a chromatographic technique.
Download or read book Liquid Chromatography written by Salvatore Fanali and published by Elsevier. This book was released on 2017-06-23 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid Chromatography: Applications, Second Edition,is a single source of authoritative information on all aspects of the practice of modern liquid chromatography. It gives those working in both academia and industry the opportunity to learn, refresh, and deepen their knowledge of the wide variety of applications in the field. In the years since the first edition was published, thousands of papers have been released on new achievements in liquid chromatography, including the development of new stationary phases, improvement of instrumentation, development of theory, and new applications in biomedicine, metabolomics, proteomics, foodomics, pharmaceuticals, and more. This second edition addresses these new developments with updated chapters from the most expert researchers in the field. Emphasizes the integration of chromatographic methods and sample preparation Explains how liquid chromatography is used in different industrial sectors Covers the most interesting and valuable applications in different fields, e.g., proteomic, metabolomics, foodomics, pollutants and contaminants, and drug analysis (forensic, toxicological, pharmaceutical, biomedical) Includes references and tables with commonly used data to facilitate research, practical work, comparison of results, and decision-making
Download or read book HPLC Columns written by Uwe D. Neue and published by Wiley-VCH. This book was released on 1997-07-28 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: An in-depth guide to HPLC column technology High-performance liquid chromatography and its derivative techniques have become the dominant analytical separation tools in the pharmaceutical, chemical, and food industries; environmental laboratories; and therapeutic drug monitoring. Although the column is the heart of the HPLC instrument and essential to its success, until now, no book has focused on the theory and practice of column technology. HPLC Columns provides thorough, state-of-the-art coverage of HPLC column technology for the practicing technician and academician alike. Along with a comprehensive discussion of the chemical and physical processes of the HPLC column, it includes fundamental principles, separation mechanisms and available technologies, column selection criteria, and special techniques. Special features include: * Comprehensive overview of state-of-the-art HPLC column technology * Explanation of the underlying principles of HPLC columns * Methods for selecting columns * Practical advice on using and applying columns, including examples * Section by M. Zoubair El Fallah on methods development * Special techniques, including preparative chromatography, continuous chromatography, and the simulated moving bed * Troubleshooting section HPLC Columns helps laboratory practitioners make better choices in column selection, methods development, and troubleshooting: it is also an excellent textbook for graduate-level courses and HPLC short courses.
Download or read book Publications of the National Institute of Standards and Technology Catalog written by National Institute of Standards and Technology (U.S.) and published by . This book was released on 1994 with total page 1162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Drug Stereochemistry written by Krzysztof Jozwiak and published by CRC Press. This book was released on 2012-04-23 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drug Stereochemistry: Analytical Methods and Pharmacology, Third Edition covers all aspects of chiral drugs from academic, governmental, industrial, and clinical perspectives, reflecting the many advances in techniques and methodology. Topics include:The use of enzymes in the synthesis and resolution of enantiometrically pure compounds in drug disc
Download or read book Selectivity and Detectability Optimizations in HPLC written by Satinder Ahuja and published by John Wiley & Sons. This book was released on 1989-06-06 with total page 642 pages. Available in PDF, EPUB and Kindle. Book excerpt: High Performance Liquid Chromatography Edited by Phyllis Brown and Richard Hartwick This contributed volume is designed to consolidate the basic theories of chromatography along with the more exciting developments in the field. This monograph addresses some questions that concern researchers in separation science, including: what is the current state of the art in liquid chromatography; has the development of liquid chromatography plateaued; if so, what new methods will take its place or complement it; and if not, where will the new frontiers be and what direction will liquid chromatography take? 1989 (0 471-84506-X) 688 pp. Quantitative Structure-Chromatographic Retention Relationships R. Kaliszan Written by a pioneer in the field, this book extends and updates research on quantitative structure retention relationships by consolidating and critically reviewing the extensive literature on the subject, while also providing the basic theoretical and practical information required in all investigations involving chromatography, analytical chemistry, biochemistry, and pharmaceutical research. Among the topics covered are the nature of chromatographic interactions, molecular interpretation of distribution processes in chromatography, topological indices as retention descriptors, and multiparameter structure-chromatographic retention relationships. 1987 (0 471-85983-4) 303 pp. Detectors for Liquid Chromatography Edited by Edward S. Yeung With its singular coverage of this fast-growing field, Detectors for Liquid Chromatography presents the state of the art in this subject area. It offers a comprehensive examination of the basic principles behind the detector response, instrumentation, and selected applications for comparison and evaluation of potential. Specifically, topics given in-depth coverage include polarimetric, indirect absorbance, refractive index detectors, absorption detectors for HPLC, FTIR and fluorometric detection, detection based on electrical and electromechanical measurements, and mass spectroscopy as an on-line detector for HPLC. 1986 (0 471-82169-1) 366 pp.
Download or read book HPLC for Pharmaceutical Scientists written by Yuri V. Kazakevich and published by John Wiley & Sons. This book was released on 2007-02-16 with total page 1136 pages. Available in PDF, EPUB and Kindle. Book excerpt: HPLC for Pharmaceutical Scientists is an excellent book for both novice and experienced pharmaceutical chemists who regularly use HPLC as an analytical tool to solve challenging problems in the pharmaceutical industry. It provides a unified approach to HPLC with an equal and balanced treatment of the theory and practice of HPLC in the pharmaceutical industry. In-depth discussion of retention processes, modern HPLC separation theory, properties of stationary phases and columns are well blended with the practical aspects of fast and effective method development and method validation. Practical and pragmatic approaches and actual examples of effective development of selective and rugged HPLC methods from a physico-chemical point of view are provided. This book elucidates the role of HPLC throughout the entire drug development process from drug candidate inception to marketed drug product and gives detailed specifics of HPLC application in each stage of drug development. The latest advancements and trends in hyphenated and specialized HPLC techniques (LC-MS, LC-NMR, Preparative HPLC, High temperature HPLC, high pressure liquid chromatography) are also discussed.
Download or read book Quality Control and Evaluation of Herbal Drugs written by Pulok K. Mukherjee and published by Elsevier. This book was released on 2019-05-30 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quality Control and Evaluation of Herbal Drugs brings together current thinking and practices for evaluation of natural products and traditional medicines. The use of herbal medicine in therapeutics is on the rise in both developed and developing countries and this book facilitates the necessary development of quality standards for these medicines.This book elucidates on various challenges and opportunities for quality evaluation of herbal drugs with several integrated approaches including metabolomics, chemoprofiling, marker analysis, stability testing, good practices for manufacturing, clinical aspects, Ethnopharmacology and Ethnomedicine inspired drug development. Written by Prof. Pulok K Mukherjee, a leader in this field; the book highlights on various methods, techniques and approaches for evaluating the purity, quality, safety and efficacy of herbal drugs. Particular attention is paid to methods that assess these drugs’ activity, the compounds responsible and their underlying mechanisms of action. The book describes the quality control parameters followed in India and other countries, including Japan, China, Bangladesh, and other Asian countries, as well as the regulatory profiles of the European Union and North America. This book will be useful in bio-prospecting of natural products and traditional medicine-inspired drug discovery and development. Provides new information on the research and development of natural remedies - essential reading on the study and use of natural resources for preventative or healing purposes Brings together current thinking and practices in quality control and standardization of herbal drugs highlighting several integrated approaches for metabolomics, chemo-profiling and marker analysis Aids in developing knowledge of various techniques including macroscopy, microscopy, HPTLC, HPLC, LC-MS/MS, GC-MS etc. with the development of integrated methods for evaluation of botanicals used in traditional medicine Assessment of herbal drugs through bio-analytical techniques, bioassay guided isolation, enzyme inhibition, pharmacological, microbiological, antiviral assays and safety related quality issues References global organizations, such as the WHO, USFDA, CDSCO, AYUSH, TCM and others to serve as a comprehensive document for enforcement agencies, NGOs and regulatory authorities
Download or read book UHPLC in Life Sciences written by Davy Guillarme and published by Royal Society of Chemistry. This book was released on 2012 with total page 467 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive overview of UHPLIC and is essential reading to newcomers to field and postgradutes and an essential handbook for experienced users of the technique.
Download or read book Handbook of Advanced Chromatography Mass Spectrometry Techniques written by Michal Holcapek and published by Elsevier. This book was released on 2017-09-07 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handbook of Advanced Chromatography /Mass Spectrometry Techniques is a compendium of new and advanced analytical techniques that have been developed in recent years for analysis of all types of molecules in a variety of complex matrices, from foods to fuel to pharmaceuticals and more. Focusing on areas that are becoming widely used or growing rapidly, this is a comprehensive volume that describes both theoretical and practical aspects of advanced methods for analysis. Written by authors who have published the foundational works in the field, the chapters have an emphasis on lipids, but reach a broader audience by including advanced analytical techniques applied to a variety of fields. Handbook of Advanced Chromatography / Mass Spectrometry Techniques is the ideal reference for those just entering the analytical fields covered, but also for those experienced analysts who want a combination of an overview of the techniques plus specific and pragmatic details not often covered in journal reports. The authors provide, in one source, a synthesis of knowledge that is scattered across a multitude of literature articles. The combination of pragmatic hints and tips with theoretical concepts and demonstrated applications provides both breadth and depth to produce a valuable and enduring reference manual. It is well suited for advanced analytical instrumentation students as well as for analysts seeking additional knowledge or a deeper understanding of familiar techniques. Includes UHPLC, HILIC, nano-liquid chromatographic separations, two-dimensional LC-MS (LCxLC), multiple parallel MS, 2D-GC (GCxGC) methodologies for lipids analysis, and more Contains both practical and theoretical knowledge, providing core understanding for implementing modern chromatographic and mass spectrometric techniques Presents chapters on the most popular and fastest-growing new techniques being implemented in diverse areas of research
Download or read book Capillary Electrophoresis Methods for Pharmaceutical Analysis written by Satinder Ahuja and published by Elsevier. This book was released on 2011-08-09 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt: Capillary electrophoresis (CE) is a powerful analytical technique that is widely used in research and development and in quality control of pharmaceuticals. Many reports of highly efficient separations and methods have been published over the past 15 years. CE offers several advantages over high-pressure or high-performance liquid chromatography (HPLC). These include simplicity, rapid analysis, automation, ruggedness, different mechanisms for selectivity, and low cost. Moreover, EC requires smaller sample size and yet offers higher efficiency and thus greater resolution power over HPLC. These characteristics are very attractive in research and development, even more so in pharmaceutical quality control (QC) and stability monitoring (SM) studies. This book will provide busy pharmaceutical scientists a complete yet concise reference guide for utilizing the versatility of CE in new drug development and quality control. - Provides current status and future developments in CE analysis of pharmaceuticals. - Explains how to develop and validate methods. - Includes major pharmaceutical applications including assays and impurity testing.
Download or read book Thin Layer Chromatography in Drug Analysis written by Lukasz Komsta and published by CRC Press. This book was released on 2013-12-20 with total page 1070 pages. Available in PDF, EPUB and Kindle. Book excerpt: Used routinely in drug control laboratories, forensic laboratories, and as a research tool, thin layer chromatography (TLC) plays an important role in pharmaceutical drug analyses. It requires less complicated or expensive equipment than other techniques, and has the ability to be performed under field conditions. Filling the need for an up-to-date, complete reference, Thin Layer Chromatography in Drug Analysis covers the most important methods in pharmaceutical applications of TLC, namely, analysis of bulk drug material and pharmaceutical formulations, degradation studies, analysis of biological samples, optimization of the separation of drug classes, and lipophilicity estimation. The book is divided into two parts. Part I is devoted to general topics related to TLC in the context of drug analysis, including the chemical basis of TLC, sample pleparation, the optimization of layers and mobile phases, detection and quantification, analysis of ionic compounds, and separation and analysis of chiral substances. The text addresses the newest advances in TLC instrumentation, two-dimensional TLC, quantification by slit scanning densitometry and image analysis, statistical processing of data, and various detection and identification methods. It also describes the use of TLC for solving a key issue in the drug market—the presence of substandard and counterfeit pharmaceutical products. Part II provides an in-depth overview of a wide range of TLC applications for separation and analysis of particular drug groups. Each chapter contains an introduction about the structures and medicinal actions of the described substances and a literature review of their TLC analysis. A useful resource for chromatographers, pharmacists, analytical chemists, students, and R&D, clinical, and forensic laboratories, this book can be utilized as a manual, reference, and teaching source.
Download or read book Separation Methods in Drug Synthesis and Purification written by Klara Valko and published by Elsevier. This book was released on 2020-06-19 with total page 790 pages. Available in PDF, EPUB and Kindle. Book excerpt: Separation Methods in Drug Synthesis and Purification, Second Edition, Volume Eight, provides an updated on the analytical techniques used in drug synthesis and purification. Unlike other books on either separation science or drug synthesis, this volume combines the two to explain the basic principles and comparisons of each separation technique. New sections to this volume include enantiomer separation using capillary electrophoresis (CE) and capillary electro- chromatography, the computer simulation of chromatographic separation for accelerating method development, the application of chromatography and capillary electrophoresis used as surrogates for biological processes, and new developments in the established techniques of chromatography and preparative methods. Features descriptions and applications of all separation methods used in the pharmaceutical industry Written by the leading scientists in their respective fields, providing solutions for a wide range of industrial separation problems encountered within the pharmaceutical industry Thoroughly updated with brand new separation science techniques and the latest developments in the established techniques of chromatography
Download or read book Characterization of Solute solvent Interactions in Gas liquid Chromatography and the Application of Multivariate Analysis to the Classification of Stationary Phase Selectivity written by Theophilus O. Kollie and published by . This book was released on 1992 with total page 1418 pages. Available in PDF, EPUB and Kindle. Book excerpt:
