Columns for modern analytical liquid chromatography

Abstract

A nalytical chemists are constantly seeking new tools which permit them to solve the increasingly complex problems with which they are confronted. Sometimes a revitalized form of an old tool appears which offers new opportunities.Liquid chromatography (lc) now fits this category. New forms of lc are now emerging which promise that this technique will be one of the most powerful and widely used analytical approaches.

Deoxygenation of solutions and its analytical applications

“…Vacuum degassing is one of the most frequently used approaches for oxygen removal (54,58,60,70,71). Decreasing the pressure above the solution allows dissolved gases to be expelled from soluticn and then removed by the vacuum pump.…”

Peer Reviewed: HPLC: Past and Present.

“…These variablewavelength UV detectors could be used for gradient or isocratic elution and allowed detection at 190-210 nm, often with a sensitivity that permitted assays in the partsper-billion range. Some samples, however, required more sensitive and/or more selective detection, which was later provided by diode-array UV-vis, electrochemical, fluorescence, and MS detectors (6). The use of diode-array UV detectors has become routine, and it seems likely that MS detectors will prove equally popular in the future, particularly for narrow-column separations.…”

“…The early days of HPLC have been reviewed (1)(2)(3)(4) and titles of related papers from 1966 to 1982 have been organized according to subtopic (5). To trace the expanding capabilities of HPLC from its beginning to the present, readers can consult three popular reference books (6)(7)(8). Also informative are the biennial analytical reviews published by Analytical Chemistry in even-numbered years.…”

Retention Behavior of Halogenated Benzenes on a Stationary Phase Having a 2,4-Dibromophenoxy Group as the Halogen Recognition Functional Group

“…2, was reversed, although their Log P values were 3.44 and 3.15, respectively. 13 The solubility parameter δ value 17 of chlorobenzene, xylene, acetonitrile and methanol was 9.6, 8.8, 11.8 and 12.9, respectively. Further, the dispersion solubility parameter δd value 17 of each solvent was 9.2, 8.8, 6.5 and 6.2, respectively.…”