The renaissance of liquid chromatography took place in the late 1960’s and early 1970’s. The first edition of this book published in 1977 described the detectors that were available at that time and which provided a performance matching that of the contemporary equipment with which they were associated. It is interesting to note that the most popular detectors then (the UV detector, the refractometer detector, the fluorescence detector and the electrical conductivity detector) are still the most commonly used detectors nearly a decade later. Detector design, however, has changed very significantly over the intervening years. Modern high efficiency columns provide very narrow peaks and very fast separations, and thus the physical design of the detectors had to change to meet these new challenges. In 1977, there was little real understanding of the important role played by the detector in the overall function of the chromatographic system and although some of the factors were pointed out in the first edition of this book, in retrospect they appeared to be little understood. This second edition gives an entirely new presentation of the subject of liquid chromatography detectors.
This interdisciplinary approach combines the chemistry and engineering involved to describe the conception and improvement of chromatographic processes. The book covers recent developments in preparative chromatographic processes for the separation of “smaller” molecules using standard laboratory equipment as well as the detailed conception of industrial chemical plants. Following an introductory section on the history of chromatography, the current state of research and the design of chromatographic processes, the book goes on to define the general terminology. There then follow sections on solid materials and packed columns process concepts. Final chapters on modeling and determination of model parameters, the design and optimization of preparative chromatographic processes and chromatographic reactors allow for the optimum selection of chromatographic systems. Essential for chemists and engineers working in the chemicals and pharmaceutical industries as well as for food technologies, due to the interdisciplinary nature of these processes.
Research into novel techniques for LC/MS continues to be a lively field, most notably regarding electrospray ionization and atmospheric pressure chemical ionization for analysis of lipids. This growing interest precipitated publication of this volume. A valuable reference and resource, Modern Methods is essential for those interested in moving into the field of lipid analysis using modern instrumentation. It describes previous work that helped establish the foundation of the discipline and demonstrates new data that is quickly defining a new level of “state-of-the-art.” Described herein are the methods that will be applied to lipids into the next decade and hopefully beyond.
Gas chromatography remains the world’s most widely used analytical technique, yet the expertise of a large proportion of chromatographers lies in other fields. Many users have little real knowledge of the variablesin the chromatographic process, the interaction between those variables, how they are best controlled, how the quality of their analytical results could be improved, and how analysis times can be shortened to facilitate the generation of a greater numberof more reliable results on the same equipment. An analyst with a more comprehensive understanding of chromatographic principles and practice, however, can often improve the quality of the data generated, reduce the analytical time, and forestall the needto purchase an additional chromatograph or another mass spectrometer.
The Second Edition of Analytical Gas Chromatography is extensively revised with selected areas expanded and many new explanations and figures. The section on sample injection has been updated to include newer concepts of split, splitless, hot and cold on-column, programmed temperature vaporization, and large volume injections. Coverage of stationary phases now includes discussion, applications, and rationale of the increased thermal and oxidative resistance of the newly designed silarylenepolysiloxane polymers. Conventional and”extended range”polyethylene glycol stationary phases are examined from the viewpoints of temperature range and retention index reliabilities, and the chapter on”Variables”has been completely rewritten. The ways in which carrier gas velocity influences chromatographic performance is considered in detail, and includes what may be the first rational explanation of the seemingly anomalous effects that temperature exercises on gas viscosity (and gas flow). The practical effects that these changes cause to the chromatography is examined in pressure-, flow-, and”EPC-“regulated systems.”Column Selection, Installation, and Use”has been completely rewritten as well. The accuracy of theVan Deemter plots has been greatly enhanced; a new program corrects for the first time for the changes in gas density and diffusion that occur during the chromatographic process because of solute progression through the pressure drop of the column. A new section has also been added on meeting thespecial requirements of columns destined for mass spectral analysis. The chapter on”Special Applications”has been expanded to include considerations of”selectivity tuning,”of fast analysis, and the section of Applications has been thoroughly updated and expanded.
Incorporates nearly 60% new material
Covers the newest concepts and materials for sample injection and stationary phases
Presents detailed consideration of the influence of carrier gas velocity on practical aspects of chromatographic performance
Contains a chapter on “Special Analytical Techniques” which includes consideration of selectivity tuning and fast analysis
Provides a new section addressing the special requirements of columns to be used in mass spectral analysis
Includes an improved program that greatly enhances the accuracy of the Van Deemter plots by more accurately depicting localized chromatographic conditions at each point in the column
Thin layer chromatography (TLC) is increasingly used in the fields of plant chemistry, biochemistry, and molecular biology. Advantages such as speed, versatility, and low cost make it one of the leading techniques used for locating and analyzing bioactive components in plants.
Thin Layer Chromatography in Phytochemistry is the first source.