Liquid chromatography working potentials

A large number of detectors has been designed for liquid chromatography and reported in the literature. Some of the ideas and concepts of several of these detectors will be described and those detectors which have potential for future work in trace analysis will be discussed. One very important area of research concerns reaction-type detection cells, and recent developments in this area will be examined in a later section. 

This kind of amperometry is the most widely used electrochemical detection method in liquid chromatography. A constant DC potential is continuously applied to the electrodes of the detector cell. The theory of amperometry with constant working potential does not differ from the theory of hydrodynamic voltammetry, even though the applied potential remains constant. 

This extends the previous work (I ) In which the Lennard-Jones type surface potential function and the frictional function representing the Interfaclal forces working on the solute molecule from the membrane pore wall were combined with solute and solvent transport through a pore to calculate data on membrane performance such as those on solute separation and the ratio of product rate to pure water permeation rate in reverse osmosis. In the previous work (1 ) parameters Involved in the Lennard-Jones type and frictional functions were determined by a trial and error method so that the solutions in terms of solute separation and (product rate/pure water permeation rate) ratio fit the experimental data. In this paper the potential function is generated by using the experimental high performance liquid chromatography (HPLC) data in which the retention time represents the adsorption and desorption equilibrium of the solute at the solvent-polymer interface. 

Calculation of Molecular Radius of Solutes. The membranes of smallest pore sizes (films 1, 7, 11, 16 and 22) were then chosen and the characteristic constants D and B, describing the interfacial attractive potential function, were determined for each solute involved in this work from experimental results of reverse osmosis and liquid chromatography. The method used was as follows ... 

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