纳米TiO_2固载脂肪酶及其固载界面表征

以3种不同形貌的纳米TiO2为载体固定化脂肪酶,研究载体形貌、酶添加量、pH值、温度和时间对固载酶活性的影响.研究结果表明,纳米线形貌TiO2固定化效果最好,最优固定化条件为加酶量0.25g/25mL溶液、pH 7.0、固载温度40℃、固载时间6.3h.利用SEM、XRD、FT-IR等对固载酶及其界面进行表征,SEM和XRD结果表明,脂肪酶吸附于纳米线TiO2载体表面,且未改变纳米线TiO2的晶型结构;FT-IR表征表明固载酶含有脂肪酶的特征吸收峰;比表面积分析显示固定化后样品的BET明显减小,表明脂肪酶在纳米线TiO2表面进行物理型吸附.

Study of nano-TiO2 immobilized lipase

This article studies three different morphologies of nano-TiO2 immobilized lipase. The impacts of the enzyme concentration, pH , adsorption time and temperature to immobilization were researched. The results show that the nanowire morphologic TiOz is the best carrier, and the optimal condition of immobilization is that the enzyme reaction solution was 0.25g/25 mL, pH of 7.0,adsorption temperature of 40 ℃ and adsorption time of 6. 3 h. SEM and XRD results show that lipase was adsorbed to the nanowire TiO2 surface without changing the crystal structure of TiO2 nanowires. FT-IR analysis show that the immobilized enzyme contains characteristic absorption peak of lipase. BET analysis shows that the BET of sample decreased after immobilization. This suggested that the adsorption of lipase on the nanowires is a physical adsorption.