纳米纤维共固定化漆酶-介体-磁性纳米金粒子的协同效应与机制

Laccases are wide distribution polyphenol oxidases with great potential applications. In order to improve stability and reduce cost, great attentions have been paid to designing and producing efficient immobilized laccase all the while. In particular, developing laccase-mediator system (LMS) to expand its use is a hotspot field. However, barely co-immobilized LMS were reported so far. In this project, laccase and TEMPO were firstly crosslinked through glutaraldehyde and grafted onto polyvinylamine respectively. Then co-immobilized laccase and TEMPO using polyvinylamine was mixed with magnetic gold nanoparticles to prepare co-immobilized laccase-mediator-magnetic gold nanoparticles system crosslinked and encapsulated into nanofiber on a certain scale by electrospinning on the basis of designing and optimization. The co-immobilized system is very easy to recycle with strengthened electron transfer and broad substrates spectra. The rule of alteration on laccase activity under nanoscale environment was explained through characterizing and analyzing the co-immobilized laccase-mediator-magnetic gold nanoparticles system. The synergistic effect and mechanism related to interaction of laccase, mediator and magnetic gold nanoparticles were investigated and revealed in the system. Alternatively, the co-immobilized laccase-mediator-magnetic gold nanoparticles system was employed to decolorize dyes and oxide aryl alcohols to test its reusability. In a word, results in this project will provide theoretical and technological support for designing novel immobilized laccase system.

漆酶是一种来源广泛且应用前景诱人的多酚氧化酶。为了提高漆酶的稳定性，降低其使用成本，开发高效的固定化漆酶一直备受关注，特别是以拓展其底物范围为目的构建的漆酶-介体系统更是研究的热点。尽管如此，迄今为止在共固定化漆酶-介体系统方面的研究几乎还是空白。本项目拟在聚乙烯胺等高分子材料接枝固载TEMPO等介体和交联固定化漆酶的基础上，与磁性纳米金粒子共混，采用静电纺丝制备尺度适宜的纳米纤维交联包埋共固定化漆酶-介体-磁性纳米金粒子系统，在强化电子传递效率、拓展底物作用范围的同时，实现固定化漆酶系统的简便高效回收。然后对该系统的酶学性质及相关参数进行分析表征，解析纳米尺度下漆酶活性的变化规律，探究该系统中漆酶、介体以及磁性纳米金粒子之间的协同效应，剖析相关机制。最后利用该系统进行染料脱色和芳醇氧化试验，考察其重复利用性能。经过本项目的系统研究，可为指导设计新型固定化漆酶系统提供理论依据和技术支撑。

漆酶是一种来源广泛且应用前景诱人的多酚氧化酶。为了提高漆酶的稳定性，降低其使用成本，开发高效的固定化漆酶一直备受关注，特别是以拓展其底物范围为目的构建的漆酶-介体系统更是研究的热点。本项目通过制备磁性Fe3O4纳米粒子，采用硅烷偶联剂对其修饰，随后用于漆酶的固定化研究，表征了固定化漆酶的酶学性质；在此基础上构建了共固定化漆酶-TEMPO系统，并应用于酸性品红脱色。通过制备磁性氧化石墨烯粒子，采用硅烷偶联剂对其修饰，用于漆酶的固定化研究，优化了固定化条件，研究了固定化漆酶的酶学性质，并在此基础上构建漆酶-TEMPO共固定化系统，用于染料脱色和构建生物传感器来检测邻苯二酚的研究。此外，通过高压静电纺丝技术获得聚乙烯醇纳米纤维，用于漆酶固定化，并表征了固定化漆酶的酶学性质。总的来说，项目利用2种磁性纳米粒子为载体，构建了2种共固定化漆酶-TEMPO系统，研究发现他们对酸性品红的脱色率可达80%以上，并实现共固定化系统重复利用10次。此外，利用几种纳米粒子固定化漆酶制备了漆酶纳米电极，通过循环伏安扫描曲线对比发现氧化石墨烯对漆酶和介体材料之间电子传递具有明显的协同增强作用。通过本项目的研究，可为构建共固定化漆酶-介体系统和高效漆酶生物传感器提供重要借鉴。