Immobilization of β‐galactosidase, albumin, and γ‐globulin on epoxy‐activated acrylic beads

Abstract

A comparative study was conducted into the immobilization of β‐galactosidase, albumin, and γ‐globulin on an epoxy‐activated polyacrylic matrix (oxirane C, Röhm‐Pharma GmbH, Darmstadt). The kinetic parameters of the immobilized β‐galactosidase were investigated with three kinds of miniaturized analytical reactors: namely, stirred batch, continuous stirred‐tank, and packed‐bed reactors. The optimum binding conditions, saturation activity and Michaelis constant of immobilized β‐galactosidase are given, together with determinations of the binding capacity of the oxirane C matrix for the three proteins investigated. For beta;‐galactosidase a saturation activity of 1300 U/g oxirane C was reached. The maximum binding, achieved by experiment, was 140 mg/g with 0.69 yield for albumin, 120 mg/g with 0.61 yield for γ‐globulin, and 40 mg/g with 0.42 yield for β‐galactosidase. From these data the inner surface of the matrix as a function of the size of the bound proteins was estimated.