【作者】 王燕佳；

【导师】 蒋惠亮；

【作者基本信息】 江南大学 ， 化学工艺， 2008， 硕士

【摘要】 聚丙烯酰胺类纳米粒子载体具有生物相容性好、无毒无味、耐酸碱、强度好等特点,可通过廉价易得的丙烯酰胺与其它单体共聚得到。其分子链中含有氨基等反应基团,具有较高蛋白质亲和性,可被广泛地进行化学改性,因而以聚丙烯酰胺类高分子合成材料开发研制脂肪酶固定化载体前景看好。本论文探索性地以聚丙烯酰胺类纳米粒子为固定化载体,采用共价键合的方法对Lipolase的固定化条件及有机相中固定化酶的催化性能进行了考察,取得了这方面结果,首先探索性的制备了小粒径单分散性好的P(AM-co-St)和P(AM-co-AAc)微球,并对各影响条件进行了讨论。其次以P(AM-co-St)为载体,固定化的最佳条件为在pH10.0的缓冲液下,吸附时间为12h,温度为35-36℃。得到的固定化酶催化合成月桂酸月桂醇酯,月桂酸与十二醇的摩尔比1:2,55℃的条件下酯化反应催化效果最好。再次通过无皂乳液聚合法探索性地制备了磁性高分子纳米微球,并将脂肪酶共价连接在微球表面。初步研究了微球直径、锰的质量分数等因素对固定化酶活力的影响。结果显示随着微球直径减小,固定化酶的偶联率和活力回收率逐渐增加。锰离子对固定化酶有明显的激活作用。最后通过分散聚合法制备了小粒径的P(AM-co-AAc)微凝胶载体,用红外光谱和扫描电镜对其进行了初步的表征。考察温度、pH、含水量、底物摩尔比、反应时间对酶活性的影响。与游离的脂肪酶相比,得到的固定化酶能有效地催化合成月桂酸月桂酯。实验同时考察了固定化酶的贮存稳定性,在4℃下放置2个月,酶活几乎没有损失。更多还原

【Abstract】 Polyacrylamide nano-particles vector has the characteristic of good biological compatibility, non-toxic and tastelessness and high bond strength, which can be obtained by copolymerization of cheap and available acrylamide and other monomers. The molecular chain containing reactive groups of amino has high protein compatibility which can be used as chemical modification. Therefore, polyacrylamide synthetic materials using as developing immobilization vector of lipase have good prospect.In this paper, Polyacrylamide nano-particles were used as immobilized carrier, immobilization conditions and catalytic properties in organic solvent of lipolase were investigated by covalent immobilization. Several aspects of results were obtained as follows: firstly, the monodisperse nanoparticles of P(AM-co-St) and P(AM-co-AAc) were prepared exploratly, and every effect condition was discussed in this paper. Secondly, the best immobilized conditions were at 35-36℃, 12h adsorption time and pH10.0 while P(AM-co-St) uesed as immobilization vector. The best catalyticeffects of esterification reaction catalysised by immobilized enzyme were at 55℃, molar ratio of lauric acid and lauryl alcohol was 1:2. Thirdly, based on the preparation of P(Am-co-St)-Mn(II) magnetic nanoparticles by emulsion, lipase was immobilized on this nanoparticles with covalent linkage. It was found that when diameter of nano-particles decreased the the coupled yield and activity of the immobilized Lipase was increased gradually. Mn(II) has obvious activation effect on immobilized enzyme. Last, based on the preparation of P(Am-co-AAc) microgel by dispersion precipitation polymerization, the microge was characterized by infrared spectrum and scanning electron microscope. The effect of temperature, pH,water content, substrate mole ratio and reaction time on enzyme activity was investigated. The immobilized enzyme could catalytic synthesis lauric acid lauryl alcohol compared with that of the free enzyme. The storage stability of immobilized enzyme was investigated, the activity of the immobilized Lipase has not been deactivated on the condition of 4℃deposited for 2 months.更多还原