摘要
以羟乙基纤维素 (HEC)和四甲氧基硅烷 (TMOS)为原料 ,利用溶胶 -凝胶技术 ,通过 TMOS的水解和缩聚反应制得了 HEC/ Si O2 凝胶复合物 ,并用此凝胶复合物对葡萄糖氧化酶 (GOD)进行包埋固定化 .探讨了给酶量、p H值和温度等因素对固定化 GOD活力的影响 ,得到的最佳固定化条件是给酶量 2 1 mg,磷酸盐缓冲液 p H值为 6.5 ,温度为 3 2℃ ,在此条件下固定化 GOD的活力可达 1 0 0 0 μmol/ (min· g) (载体质量以干态为基准 )以上 ,约为游离 GOD活力的 5 0 % .同时研究了固定化 GOD的基本性质 ,结果表明 ,固定化 GOD的最适 p H值和最适温度分别为 5 .2和 3 2℃ ,米氏常数 Km 为 7.94mmol/ L,与游离 GOD相比 ,固定化 GOD的反应稳定性。
Hydroxyethyl cellulose/silicon dioxide gel composites(HEC/SiO 2) prepared by a sol gel method through the hydrolysis and polycondensation of tetramethoxy silicane in a hydroxyethyl cellulose aqueous solution. The gel composites are used as carriers for immobilization of glucose oxidase(GOD). The effects of enzyme content given, phosphate buffer pH, and immobilizing temperature on the activity of immobilized GOD are discussed. The optimum conditions obtained as follows:enzyme content given 21 mg, phosphate buffer pH=6 5, immobilizing temperature 32 ℃. Under the optimum conditions, the bioactivity of the immobilized GOD was as high as 1 000 μmol/(min·g) (dried carrier), about 50 percentage of that of free GOD. The basic proporties of the immobilized GOD are also studied. The results showed that the optimum pH of resultant immobilized GOD and temperature for immobilization were 5 2 and 32 ℃, respectively. The Michaelis constant( K m) is 7 94 mmol/L .
出处
《应用化学》
CAS
CSCD
北大核心
2002年第2期153-157,共5页
Chinese Journal of Applied Chemistry
