ADSORPTION AND SEPARATION OF PROTEINS ON COMPOSITE ANION-EXCHANGERS WITH POLY(N-DIETHYLAMINOETHYLACRYLAMIDE) BONDED PHASES

Composite anion exchangers for chromatography of proteins were prepare d by chemical adsorption of poly(p-nitrophenyl acrylate) on gamma-amin opropylsilicas followed by coupling of the esters to 2-diethylaminoeth ylamine. Separation of standard proteins (bovine serum albumin and ova lbumin) on these anion exchangers established their enhanced selectivi ty and milder desorption conditions as compared with polyethyleneimine silicas and DEAE-Toyopearl 650M. Frontal analysis was used to evaluate the maximum binding capacity for ovalbumin adsorption on the new pack ing, which was found to be 13 mg/ml and so nearly half those observed with polyethyleneiminesilicas of comparable pore diameter. The possibl e role of the excluded volume of the attached polymer is discussed wit h respect to the adsorptivity of the composite ion exchangers.