摘要
通过逐层自组装技术成功地把超氧化物歧化酶 (SOD)吸附在聚苯乙烯 (PS)胶体粒子表面 .zeta电位和 TEM证明了聚阳离子或聚阴离子型 SOD与相反电荷的聚电解质在 PS胶体粒子表面的交替吸附 .通过测定 SOD被胶体粒子吸附后上清液的生物活性 ,得到聚阴离子型 SOD(p H=8.0 )和聚阳离子型 SOD(p H=4.3 )在 PS胶体粒子表面的吸附量分别为 1 2和 5 1 IU,相对活性分别为 2 3 .4%和 2 .9% .聚阴离子型 SOD在PS胶体粒子表面能形成平滑规整的膜 ,导致较高的相对活性 .研究结果表明 ,通过调节 p H值 。
Novel enzyme multilayer films on the surface of polystyrene(PS) colloid particles was fabricated by layer-by-layer(LbL) self-assembly. Superoxide dismutase(SOD) was adsorbed on the PS particles as either polycation or polyanion switched by adjusting pH alternatingly with the oppositely charged polyelectrolytes. zeta-Potential and TEM results indicated the regular and stepwise growth of the multilayer structure. The amount of the immobilized SOD was estimated from the difference in SOD bioactivity of the supernatant after adsorption and SOD solution before adsorption by using the pyrogallol oxidation method. The immobilization amount of SOD was 12 and 51 IU when adsorbed in pH=8.0 as a polyanion and in pH=4.3 as a polycation, respectively. However, the relative activity of the former was 23.4% while that of the latter was 2.9%, compared to that of free SOD in aqueous solution. Anionic SOD was found to form more regular and smooth layers on the PS particle surface and cationic SOD to aggregate. By adjusting pH of the adsorption solution we can optimize the assembled status and bioactivity of particle-immobilized enzyme.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2005年第1期88-92,共5页
Chemical Journal of Chinese Universities
基金
国家自然科学基金 (批准号 :90 2 0 60 10 )
广东省自然科学基金 (批准号 :0 3 13 80 )
广州市科技计划项目资助
关键词
超氧化物歧化酶
逐层自组装
固定化酶
聚电解质多层膜
PS胶体粒子
Superoxide dismutase(SOD)
Layer-by-layer self-assembly
Immobilized enzyme
Polyelectrolyte multilayer films
PS colloid particle
