多孔St/DVB共聚微球用于静电自组装脂肪酶

Porous St/DVB Copolymer Microspheres for Immobilization of Lipase by Layer-by-Layer Selfassembly

将酶与带相反电荷的聚电解质在单分散疏水多孔St/DVB共聚微球表面交替吸附静电自组装多层脂肪酶膜.确定了静电自组装单层酶膜的最佳条件为酶与载体的质量比3:1,吸附时间0.5h,pH5.5.在上述条件下静电自组装3层脂肪酶膜,结果表明,当最外层为酶层时,组装2层酶的活性比单层酶提高24%,组装3层酶的活性比2层酶的活性稍有增加.在酶液pH7.5的条件下,考察了聚电解质中的离子强度对静电自组装各层酶活力的影响,结果表明,当最外层为酶层或聚电解质层时,酶的活力随层数增加而下降.

Lipase layers, being separated by polyelectrolyte [poly（diallyldimethylammonium chloride）] with opposite electric charges each by each （PDADMAC）, were deposited onto porous S/DVB copolymer microspheres with hydrophobic surface using layer-by-layer selfassembly. The optimal conditions for the selfassembly of single lipase layer were determined as pH 5.5, adsorption time 0.5 h, ratio of lipase to carriers 3：1 （mass ratio）. Three lipase layers were assembled onto porous St/DVB copolymer microspheres based on the above optimal conditions. The experimental results showed that the activity of two lipase layers increased 24% comparing with that of single lipase layer and the activity of three lipase layers increased slightly comparing with that of two lipase layers when the outermost layer was lipase. In addition, under the pH of lipase solution of 7.5, the influence of ion strength of PDADMAC solution on the different layer of selfassembly of lipase was also investigated. The result showed that the activity of lipase decreased with the increase of layer number when the outermost layer was either lipase or PDADMAC.