Immobilization and stabilization of alcohol dehydrogenase on polyvinyl alcohol fibre

A polyvinyl alcohol (PVA) fibrous carrier has been chemically modified for the immobilization of yeast alcohol dehydrogenase (ADH) with an aim to increase its stability over a wide pH range, prolong its activity upon storage, and enhance its reusability. The strategy for immobilization involved functionalization of the fibrous carrier with chloropropinoyl chloride followed by amination with ethylenediamine. Tethering of the ADH enzyme to the PVA scaffold was achieved with glutaraldehyde. The activity profile of the immobilized enzyme was compared to soluble enzyme as a function of pH, temperature and reusability. The immobilization of ADH on PVA fibrous carrier shifted the optimal reaction pH from 7 to 9, and improved the thermostability at 60 °C. Furthermore, the immobilized enzyme retained 60% of its original activity after eight cycles of reuse. These results demonstrate that PVA based textiles can serve as a flexible, reusable carrier for enzyme immobilization.