EFFECT OF POLYMER MATRIX ON PENICILLIN ACYLASE IMMOBILIZATION ON COPOLYMERS OF BUTYL ACRYLATE AND ETHYLENE-GLYCOL DIMETHACRYLATE

Copolymers of butyl acrylate and ethylene glycol dimethacrylate with v arious degree of crosslinking and aminolysis were used for penicillin acylase immobilization. The amount and activity of the bound protein d ecreased with the decrease of crosslinking when copolymers having near ly constant degrees of aminolysis were compared. The increase of the c arrier amino group content increased the ability to bind the protein ( by glutaraldehyde method) without a proportional rise of enzyme activi ty. The comparative studies of immobilization effect and performance o f the derivatives showed 40 % crosslinked EGDMA, having an amino group content of 0.67 mmol g-3, to be the carrier of choice. This selected carrier was tested for active protein immobilization by use of crude a cylase preparation. It was shown that up to a protein concentration of 9 mg cm-3 in the immobilization mixture the active protein was prefer entially bound to the polymer matrix. It was indicated also that the d erivative stability was mostly affected by multipoint attachment of th e enzyme to the carrier surface.