【摘要】 以壳聚糖作为载体,戊二醛作为交联剂对脲酶进行固定化。固定化的最适条件为:酶的偶联时间60min,戊二醛浓度0.5%,pH值7.0。对游离及固定化脲酶的酶学性质研究表明,酶促反应的最适pH均为7.0,最适温度分别为33℃和70℃。米氏常数分别为29.8mmol/L和13.9mmol/L。与游离酶相比,固定化酶的热稳定性和贮存稳定性更佳。应用固定化酶测定了试样中的微量组分。更多还原

【Abstract】 Urease was immobilized on chitosan with glutaraldehyde as the crosslinking reagent.Under the optimum conditions,chitosan was crosslinked with 0.5% glutaraldehyde in the enzyme solution(pH 7.0) and reacted with urease for 90 min.The study on the enzymatic characteristics of free and immobilized urease indicated that optimum pH value of the enzymatic reaction was 7.0,and the optimum temperatures were 33 ℃ and 70 ℃,respectively.The Km values for urea were 29.8 mmol/L(free) and 13.9 mmol/L(immobilized),respectively.It indicated that the immobilized enzyme has better thermal stability and storage stability.The immobilized urease has been used to determine trace components in samples.更多还原