EVALUATION OF POLY(BUTYL ACRYLATE-CO-ETHYLENE GLYCOL DIMETHACRYLATE) SORBENTS FOR CHROMATOGRAPHIC-SEPARATION OF BIOMOLECULES

Copolymers of butyl acrylate (BA) crosslinked with ethylene glycol dimethacrylate (EGDMA) were evaluated as potential chromatographic packings. It was found that slightly crosslinked copolymers (up to 30 wt.-% EGDMA) did not provide porous material, while for matrices which exceeded 40 wt.-% of EGDMA the porous structure remained unchangeable. The increase of crosslinker content mostly affected the surface hydrophobicity. Two methods of measurement of this property were discussed: Sorption of alkyl alcohols and amino acids. Taking the latter for testing, a polymer matrix hydrophobicity index was calculated as the slope of dependence of column capacity vs. amino acid hydrophobicity parameter. The indices were verified against well-established interaction energies of -CH2- groups of alkyl alcohols and polymer surfaces. Some benefits of the use of the hydrophobicity index in evaluation of polymer sorbents were demonstrated.