ELVACITE-2669 AS PSEUDOSTATIONARY PHASE - ELECTROKINETIC CAPILLARY CHROMATOGRAPHY AND LIGHT-SCATTERING STUDY

The applicability of a polyelectrolyte, Elvacite 2669, as a pseudostat ionary phase in capillary electrokinetic chromatography for the separa tion of some neutral hydrophobic compounds was investigated. In additi on, its behavior in buffer solutions for capillary electrophoretic sep arations was studied by dynamic light scattering. With the polymer con centration held constant and the methanol-water ratio varied, study wa s made of the viscosity, the migration times of some neutral hydrophob ic compounds, and the light scattering properties of the buffers. The effect of varying the polymer concentration on the separation of the c ompounds was also investigated. All studies were made under basic cond itions. Data on the aggregation behavior, including the size and aggre gation number of the polyelectrolyte under different conditions, are g iven and the capillary electrophoretic results are interpreted in term s of the dynamic light scattering data. In addition, the interaction o f Elvacite 2669 with the fused silica wall was investigated, and the r esults showed that polymer adsorption onto the capillary wall occurred at polymer concentrations at and above 0.5 wt%. Both the capillary el ectrophoretic and dynamic light scattering results showed the behavior of Elvacite 2669 to be highly dependent on the methanol-water ratio i n the buffer. (C) 1998 John Wiley & Sons, Inc.