静电纺PMACAA纳米纤维膜固定化辣根过氧化物酶的研究

Immobilization of horseradish peroxidase on electrospun PMACAA nanofibrous membrane

首先采用溶液聚合法制备丙烯酸甲酯-丙烯酸共聚物(PMACAA),借助静电纺丝技术制备PMACAA纳米纤维膜,利用EDC/NHS活化羧基,共价结合法固定化辣根过氧化物酶(HRP)。SEM和FT-IR分别对纤维形貌和化学特性进行表征,研究了固定化时间对载酶量的影响,HRP固定化前后的pH稳定性、热稳定性、重复使用性、储存稳定性,并探究了固定化HRP对4-硝基苯酚(PNP)的去除率。结果表明:固定化HRP的纤维直径增加,固定化HRP最大载酶量达到88.27mg/g,固定化HRP稳定性和重复使用性都得到很大提高,重复4次使用后酶活性仍保持在初始活性的76%,与游离酶对PNP去除率(82%)相比,固定化HRP表现出更高的去除率(52%)。

Poly（methyl acrylate-co-acrylic acid）（PMACAA）nanofibrous membrane was prepared by a combination of solution polymerization method and electrospinning technique. Horseradish peroxidase （HRP）was then immobilized on the membrane by using EDC/NHS as coupling agent. The results of SEM showed that nanofibrous diameter of immobilized HRP was increased,The chemical properties of membrane were characterized with infrared spectroscopy. The parameters and p-nitrophenol （PNP）removal rate about immobilized HRP were studied. The results showed that HRP loading reached 88.27 mg/g membrane. Both stability and reusability of HRP were greatly improved after immobilization. After four treat- ment cycles,immobilized HRP retained about 76 % of its initial activity. Additionally, the immobilized HRP exhibited better removal efficiency for PNP in 60min （82%）compared with free HRP （52%）.