Immobilized lipase on porous silica beads: preparation and application forenzymatic ring-opening polymerization of cyclic phosphate

Porcine pancreas lipase (PPL) immobilized on porous silica beads and employ ed successfully for ring-opening polymerization of ethylene isobutyl phosph ate (EIBP) was investigated. The factors affecting the activity of the immo bilized lipase were studied. A good coupling yield was achieved - 41.88 mg of native lipase/g of porous silica beads. We also studied the thermal prop erties of this immobilized lipase. The optimum temperature of this immobili zed lipase was 70 degreesC. After incubation at 90 degreesC for 1 h, the ac tivity of immobilized lipase remained above 70%. An enzyme-catalyzed ring-o pening polymerization was achieved in bulk with Mn values ranging from 1642 to 5783 g/mol. It was found that recovered immobilized lipase was more act ive for the polymerization of EIBP than in the first use and Mn was signifi cantly increased. The higher molecular weight can be gained with the propri ety amount of immobilized lipase and a higher temperature. (C) 2001 publish ed by Elsevier Science B.V.