A review of: “HANDBOOK OF AFFINITY CHROMATOGRAPHY”

Abstract

T. Kline, Ed. Marcel Dekker, New York, 1993; hardbound, viii + 332 pages, $135.00     

A GENERALIZED EQUATION FOR HETP IN COLUMN CHROMATOGRAPHY

Based on an axial dispersion model, a generalized equation for HETP in column chromatography ispresented. From this equation, Van Deemter's equation for packed column and Golay's for capillary col-umn can be derived under simplified conditions. The generalized equation can be used to obtain variousempirical equations for HETP and gives physical significance to the empirical constants in them. It isadaptable to all column chromatography including packed and capillary columns as well as gas andliguid chromatography.     

A review of: “AQUEOUS TWO-PHASE PARTITIONING”

Abstract

B.Y. Zaslavsky. Marcel Dekker, New York, 1994; hardbound, pp. xiii+696, $165.00     

A review of: “Gas Separation Technology”

Abstract

E.F. Vansant and R. Dewolfs, Eds. Elsevier, Amsterdam, 1990; (Process Technology Proceedings, 8), hard bound, 700 pages, $233.00     

A review of: “The Handbook of Environmental Chemistry”

by Otto Hutzinger, University of Amsterdam and 52 authors from 8 countries, Springer-Verlag Berlin     

A UNIFIED RETENTION MODEL OF SOLUTE IN LIQUID CHROMATOGRAPHY

Based on six thermodynamic equilibria,a unified retention model of solute in liquidchromatography(LC)is first proposed.The unified model was tested and proved to be valid for a LC sys-tem with mobile phase consisting of a complete range of multiple,ternary or binary components and eachkind of LC except size exclusion chromatography.In addition,so long as making some assumptions andmathematical conversions,the expressions of various popular models in LC can be derived by using theunified model.     

A review of: “Adsorption Processes for Gas Separation”

Abstract

F. Meunier and M. D. Le Van, Eds. Technique et Documentation-Lavoisier; 14, rue de Provigny 94236 Cachan cedex, France. (Recents Progres en Genie des Procedes, No. 17, Vol 5, 1991), paper back, 260 pages     

A review of: “From Chemical Topology to Three-Dimensional Geometry”

Abstract

Balaban, A. T. (1997). Plenum Press, New York. 420 pp. Hardcover, ISBN: 0-306-45462-9, US$125.00. (ordering information can be obtained from: http://www.plenum.com)     

α-thiocyanation of carbonyl compounds: A review

The α-thiocyanation of carbonyl compounds is one of the most important processes in synthetic organic chemistry. These compounds are important precursors for the production of various biologically important heterocyclic compounds and other industrially important products. Ammonium thiocyanate (NH₄SCN) is a key reagent for the production of such a class of thiocyanate intermediates. In addition to the inherent efficiency issues, there are also environmental concerns that need to be addressed. Therefore, in recent years considerable advances have been made for the synthesis of α-thiocyanation of carbonyl compounds with high selectivity and yield. In this review, we have summarized various methods for the synthesis of α-thiocyanation carbonyl compounds.     

A NOVEL DERIVATIVE OF β-CYCLODEXTRIN AS CHIRAL SIATIONARY PHASE IN CAPILLARY GAS CHROMATOGRAPHY

A novel β-cyclodextrin derivative, 2, 6-di-O-butyl-3-O-acetyl-β-cyclodex-trin, was prepared and used as chiral stationary phase for capillary gas chromato-graphic resolution of enantiomers, lhe glass capillary columns with the derivativehaving low melting point and high thermal stability could produce more than 3000plates per column meter and have proven to be good chlral columns to separate theenantiomers of some amino acids, derivatives of epoxy ethane and alkyl halide, etc.     

A STOICHIOMETRIC DISPLACEMENT MODEL FOR RETENTION OF SOLUTE IN LIQUID CHROMATOGRAPHY WITH MULTI-COMPONENT SYSTEM

Considering all the kinds of interactions between solute and solvent, solute and stationary phase, solvent and stationary phase molecules as well as the competitional adsorption among various kinds of solvent molecules on the stationary phase, we present a stoichiometric displacement model of solute retention with four sets of parameters in liquid chromatography. This model was tested with data from both literature and experiments done by ourselves. These results show that this model may fit the experimental data for a liquid chromatography system with various kinds of mobile phases consisting of a complete range of multi-components and with different types of stationary phases.     

PEAK IDENTIFICATION FROM INTERACTION INDEX IN REVERSED-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY

The interaction index c which was derived from the fundamental retention equationlogk' =a + cC_B in reversed--phase high--performancc liquid chromatography (RP-HPLC) quan-titatively describes the difference in the interaction between solute--strong. solvent andsolute--weak solvent; it has shown to be a constant for a specific solute even when columnsystems with different C18 packings are used. The theoretical basis for peak identificationby using interaction index has been proposed, which was based on the a,c values on stan-dard C18 column by utilizing linear a-a plots on column pairs and the linear relationship be-tween parameters a and c for the structural related compounds. Through the establishmentof parameters a,c data based on the standard C18 column for a certain type of compounds,the retention of thesc compounds on various C18 columns can be predicted. Typical exam-ples have been given to verify the correctness of this method.     

OPTIMIZATION OF MULTI-STEP LINEAR PROGRAMME TEMPERATURE IN CAPILLARY GAS CHROMATOGRAPHY

An optimal method to select the optimal temperature of multi-step linear programme temperature in capillary gas chromatography, by simultaneously considering the effects of column temperature and differences of column distance to be moved on resolution and analytical times, has been developed. We called this optimal method a moving overlapping resolution mapping method because the immigrating position of solute in column is traced. The validity of this optimal method has been verified.     

Bioanalytical chemistry of cytokines – A review

Cytokines are bioactive proteins produced by many different cells of the immune system. Due to their role in different inflammatory disease states and maintaining homeostasis, there is enormous clinical interest in the quantitation of cytokines. The typical standard methods for quantitation of cytokines are immunoassay-based techniques including enzyme-linked immusorbent assays (ELISA) and bead-based immunoassays read by either standard or modified flow cytometers. A review of recent developments in analytical methods for measurements of cytokine proteins is provided. This review briefly covers cytokine biology and the analysis challenges associated with measurement of these biomarker proteins for understanding both health and disease. New techniques applied to immunoassay-based assays are presented along with the uses of aptamers, electrochemistry, mass spectrometry, optical resonator-based methods. Methods used for elucidating the release of cytokines from single cells as well as in vivo collection methods are described.     

A Review of: “Unified Separation Science”

Abstract

J. C. Giddings, Wiley/Interscience, New York, 1991, hardbound, 320 pages, $54.95     

THE THEORETICAL STUDY ON INTERSECTION POINT RULE FOR HOMOLOGUES IN GAS CHROMATOGRAPHY

The intersection point rule for homologues in gas chromatography was discovered manyyears ago,now more and more application and development are occurring in recent years~[2-6],but there are few systemic theoretical studies.In this paper,based on the basic equation of reten-tion values in gas chromatography,we prove the intersection point rule of homologues frommathematics,study the factors affecting intersection point position,give the physical meaning ofintersection point,and explain the experimental rules in references.     

TETRATHIAFULVALENE S-OXIDE: A FATAL “DONOR IMPURITY” IN THE ORGANIC METAL TTF-TCNQ

Abstract

Tetrathiafulvalene S-oxide (TTF-ox) was first detected by mass spectrometry in samples of Tetrathiafulvalene (TTF) which had been exposed to oxygen. Pure TTF-ox was prepared by peracid oxidation of TTF and isolated as a relativly stable solid. Physical data will be presented.