掺杂固定化酶柱的次黄嘌呤液滴光化学传感器研究

Doped Sol-Gel Method for Immobilizing Enzyme and Its Application in Hypoxanthine Biosensor Based on Liquid Droplets

研制了一种基于掺杂的溶胶-凝胶固定化酶柱的次黄嘌呤液滴光化学传感器.在凝胶形成过程中添加肌氨酸和山梨醇,由于两种添加剂的模板作用,可形成大而有序的凝胶网格,使得酶与底物能充分接触,从而达到提高传感器响应速度和灵敏度的目的.基于这一方法固定了黄嘌呤氧化酶,并结合液滴光化学传感装置,用于次黄嘌呤的测定.在pH值为8.74的Tris-HCl缓冲液中,该传感器对2.0×10^-7～8.0×10^-6 mol/L的次黄嘌呤呈线性响应,检出限为5.0×10^-8 mol/L.本实验固定化黄嘌呤氧化酶的催化效率是普通溶胶-凝胶法固定化酶的2.54倍.

A strategy for fabricating hypoxanthine drop sensor has been described by the addition of sarcosine and D-sorbitol during the immobilization of xanthine oxidase into sol-gel processed materials. The study suggested that the addition of sarcosine and D-sorbitol during encapsulation increased the biocatalytic activities of immobilized enzyme by up to 2.54-fold relative to that of undoped activity upon addition of sarcosine and D-sorbitol may be due to the glasses. The improvements in enzyme increase of the pore size of hydrogel network, so that the diffusion rate for substrate molecules to entrapped enzyme would be increased. Based on the technique for immobilizing enzyme, a liquid drop sensor was developed to determine hypoxanthine. In pH 8.74 Tris-HCl buffer solution, the biosensor analytical working range was 2.0 × 10^-7 -8.0 × 10^-6 mol/L, with a detection limit of 5.0 × 10^ -8 mol/L.