The preparation, properties and applications of nylon-tube immobilised catalase

Abstract

1. Several nylon-tube immobilised catalase derivatives were prepared. The method of preparation of nylon-tube for enzyme attachment was varied in an attempt to obtain the most active immobilised catalase derivative. 2. The stability of nylon-tube immobilised catalase derivatives during constant perfusion with hydrogen peroxide was examined in an attempt to prepare the most stable immobilised enzyme. 3. The peroxidatic activity associated with nylon-tube immobilised catalase derivatives was investigated. The effect of the chemistry of immobilisation, the length and diameter of the nylon-tube, and methanol concentration on the peroxidatic : catalatic activity ratio displayed by the immobilised catalase derivatives. 4. The applications of nylon-tube immobilised catalase derivatives in automated analysis was considered. Glucose was determined by four different assay protocols, involving 1) nylon-tube co-immobilised glucose oxidase and catalathe ; 2) nylon-tube immobilised derivatives of glucose oxidase and catalase in series ; 3) nylon-tube immobilised derivatives of glucose oxidase, catalase, and aldehyde dehydrogenase in series ; 4) nylon-tube co-immobilised glucose oxidase and catalase in conjunction with an oxygen electrode. 5. The peroxidatic activity of catalase was monitored using a) Hantzsoh reaction ; b) Aldehyde dehydrogenase ; and c) flow-through oxygen electrode. The four analytical systems were calibrated with aqueous glucose standards and the assay sensitivity and immobilised enzyme stability determined. Comparisons were drawn between the four methods for glucose determination using nylon-tube immobilised enzymes.