果胶改性纳米纤维制备及其在固定化酶中的应用

摘要

基于静电纺丝技术制备共聚物PM M A-co-PAA纳米纤维,利用生物聚合物果胶对纳米纤维改性,增强纤维的生物相容性,研究改性后纳米纤维对酶的固载量及固定化酶的稳定性的影响.实验表明:经果胶改性后,由于侧链引入了大量的极性基团,纳米纤维的亲水性得到改善.当果胶的质量浓度为0.15 mg/mL时,酶的固载量达到150 mg/g,此外,相比于未经改性的纳米纤维,经改性后的固定化酶有较高的温度、pH和储存稳定性.pH在5~9,温度在20 ℃~60 ℃范围内时,改性纳米纤维固定化酶在最低点的相对活性相比未改性纳米纤维固定化酶提升2.2倍和1.7倍;50 ℃储存10 h后,改性前后纳米纤维固定化酶相对酶活相差3.7倍.%Pectin-functionalized polymethylmethacrylate-co-polyacrylic acid(PMMA-co-PAA)nanofibers have been successfully synthesized via electrospinning technique.The morphologies and properties of PMMA-co-PAA@ pectin nanofibers were investigated through different analytical tools.The as-prepared PMMA-co-PAA@ pectin nanofibers were employed as carriers for lipase immobilization.A maximum loading amount of lipase(150 mg/g)can be achieved.The resulting PMMA-co-PAA@ pectin-Candida antarctica lipase B(CALB)can function as an active and recyclable nanobiocatalyst,which shows high stability even under a broad pH value of 5~9,temperature range of 20 ℃ ~60 ℃ and storage time at 50℃ for 2~10 hours.