Trypsin was covalently linked to Eudragit S-100 an enteric coating polymer by carbodiimide coupling method. Nearly
90% of enzyme activity was conjugated to the polymer whereas actual observed expressed activity was 64%. The enzyme
bound to the polymer by simple adsorption as well but leached off the polymer in the presence of high ionic strength (1.0 M
NaCl)The immobilized enzyme showed stability to autolysis at 458C and had a marginal shift in pH optimum. The Km
value of the enzyme decreased from 1.0=10y3 M to 0.7=10y3 M on immobilization. The soluble Eudragit-trypsin conjugate was used to hydrolyze casein at 458C. Eudragit being a reversibly soluble–insoluble polymer, the biocatalyst could be recovered and reused.