Download or read book Effect of Bonded chain Rigidity on Selectivity in Reversed phase Liquid Chromatography written by June Frances Mullaney and published by . This book was released on 1986 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Encyclopedia of Chromatography written by Jack Cazes and published by CRC Press. This book was released on 2009-10-12 with total page 2968 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thoroughly revised and expanded, this third edition offers illustrative tables and figures to clarify technical points in the articles and provides a valuable, reader-friendly reference for all those who employ chromatographic methods for analysis of complex mixtures of substances. An authoritative source of information, this introductory guide to specific chromatographic techniques and theory discusses the relevant science and technology, offering key references for analyzing specific chemicals and applications in industry and focusing on emerging technologies and uses.

Download or read book Shape Selectivity and Stationary Phase Conformation of Bonded Phases in Reversed phase Liquid Chromatography written by Luxsana Limsavarn and published by . This book was released on 2003 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chromatography Abstracts written by and published by . This book was released on 1986 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Molecular Basis of Chromatographic Separation written by Esther Forgacs and published by CRC Press. This book was released on 1997-07-03 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chromatographic separation is widely used in many scientific disciplines today, having an ever increasing number of scientific and technological applications. The widespread use of this rapid and powerful technique requires that it be fully understood, so that the most suitable may be determined for each possible separation problem in each possible domain of scientific research and technology. Molecular Basis of Chromatographic Separation provides complete coverage of the practical and molecular aspects of this popular technique. It compiles and evaluates recent results, outlines available methods, and discusses how to select the best method for a particular application.

Download or read book Understanding Retention Mechanisms and Adjusting Selectivity of Basic Pharmaceutical Separations by Reversed phase Liquid Chromatography written by Jun Dai and published by . This book was released on 2005 with total page 626 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2004 with total page 882 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Attempt Directed Toward Enhanced Shape Selectivity in Reversed Phase Liquid Chromatography Preparation of the Dodecylaminated Cyclodextrin Bonded Phase written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Study of Retention Mechanism in Reversed Phase Liquid Chromatography written by Lay Choo Tan and published by . This book was released on 1994 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Mobile Phase Composition on Steroid Retention and Selectivity in Reverse phase Liquid Chromatography written by Evan Li and published by . This book was released on 2017 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Comprehensive Dissertation Index written by and published by . This book was released on 1989 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Index to American Doctoral Dissertations written by and published by . This book was released on 1986 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Phenomenological Investigation of N ALKLY Bonded Phases in Reversed phase Liquid Chromatography written by Shih Hsien Hsu and published by . This book was released on 1986 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigating Reaction Schemes for Improving Silica Based Monomeric Bonded Stationary Phases for Reversed Phase Liquid Chromatography written by Michael David Bair and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Central to the advancement of reversed-phase high-performance liquid chromatography (RPLC) is to develop new synthetic strategies for manufacturing stationary phase materials. Methods to improve the efficiency, retention properties, and chemical stability of stationary phases are always being investigated. The work presented focuses on two new synthesis schemes aimed at improving monomeric silica-based stationary phases in these respects. The first study involves "pre-capping" Type-B silica. Previous work showed that monomeric stationary phases made by pre-treating the silica surface with small amounts of trimethylsilane (TMS) reagents prior to C18 silanization showed vast improvements in the chromatographic efficiency, phase loading, and retention with a maximum at approx. 5% pre-capping. It was concluded that this pre-capping step improved efficiency by selectively neutralizing the most reactive highly-acidic silanol sites, so-called silanol "hot spots," producing a more energetically-homogenous surface prior to exhaustive C18 derivatization that subsequently yielded a more evenly-distributed alkyl bonding arrangement. These previous studies were performed on Type-A silica, an older variety of silica gel material containing higher levels of metal impurities than the Type-B silica used today. It has since been argued that metallic impurities are the primary cause of silanol hot-spots, and that pre-capping Type-B silica would have little or no effect, however the experimental evidence has yet to be produced, and there exists the potential for heterogeneous silanol reactivity inherent in the amorphous silica gel regardless of purity. The purpose of the work presented here is to determine the effects of TMS pre-capping on Type-B silica as compared to the previous Type-A results, with the goal of establishing pre-capping protocol for Type-B silica and to form a better understanding of its chemistry. The current work performed on three Type-B silica substrates of various physical and chemical properties demonstrated optimal TMS pre-capping at approximately 2.5%. The results at this level show only a slight improvement in efficiency for non-polar compounds ( 25%) was observed for some drug compounds and bases under buffered conditions, with the magnitude of the improved efficiencies correlating with metal impurity content and physical parameters of the silica substrate. Pre-capping also resulted in a slight decrease in retention and hydrolytic stability due to a decrease in bonded phase density. The results lend supporting evidence that metal impurities are the primary source of highly acidic silanols, but they also suggest a means to improve efficiency of basic analytes on certain Type-B silica substrates. It was concluded that TMS pre-capping Type-B silica is best done at low levels (

Download or read book THE CHARACTERIZATION OF BONDED PHASES FOR HIGH PERFORMANCE LIQUID CHROMATOGRAPHY written by and published by . This book was released on 1980 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The physical and chemical nature of chemically bonded phases used in high performance liquid chromatography have been studied. These bonded phases were characterized by a variety of chromotographic and non-chromatographic experiments. The non-chromatographic techniques included 13C NMR and batch extraction methods. The role played by the bonded phase as well as the mobile phase in determining the retention characteristics of the "stationary phase" were determined. The retention of solute molecules on bonded phases was found to be a function of the chain length of the bonded phase, the chemical nature of the bonded molecule, and the type of organic modifier used in the mobile phase. The energetics of the solute-stationary phase interactions was determined by the differential enthalpy and was found to be indicative of a partitioning process between two liquid phases. The retention process was also affected by the surface coverage of the bonded molecule. Optimum retention and separation characteristics were obtained with a hydrocarbon bonded phase of high surface coverage when used with a mobile phase containing a very polar organic modifier. The efficiency of these bonded phases was found to be independent of chain length as well as surface coverage of the bonded molecule. Some bonded phases which have specific functionalities incorporated into the bonded molecule are not true reversed phases. The selectivity of the bonded phases towards polar solute molecules was found to be affected by the type of organic modifier used in the mobile phase. The major accomplishment of this work shows that the stationary phase consists of the bonded molecule as well as trapped mobile phase. The composition of this ternary mixture is a function of the type and amount of bonded material and the type and amount of organic modifier used in the mobile phase

Download or read book Liquid Chromatography written by Salvatore Fanali and published by Elsevier. This book was released on 2017-06-22 with total page 808 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid Chromatography: Fundamentals and Instrumentation, 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 understanding of new fundamentals and instrumentation techniques 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