Abstract:
The potential application of biodevices based on enzymatic bioelectrocatalysis are limited by poor stability and electrochemical performance. To solve the limitation, modifying enzyme with functional polymer to tailor enzyme function is highly desirable. Herein, glucose oxidase (GOx) was chosen as a model enzyme, and according to the chemical structure of GOx cofactor (flavin adenine dinucleotide, FAD), we customize a biomimetic cofactor containing vinyl group (SFAD) for GOx, and prepared an GOx nanocapsule via in-situ polymerization. The characterization of particle size distribution, TEM, fluorescence and electrochemical performance indicated the successful formation of electroactive GOx nanocapsule with SFAD-containing polymeric network (n (GOx-SFAD-PAM)). The network can act as an electronic \"highway\" to link the active site with electrode, with capability to accelerate electron transfer as well as enhanced GOx stability. Further investigation of bioelectrocatalysis shows that n (GOx-SFAD-PAM)-based biosensor has low detection potential (-0.4 vs. Ag/AgCl), high sensitivity (64.97 μAmM-1cm-2), good anti-interference performance, quick response (3⁓5s) and excellent stability, and that n (GOx-SFAD-PAM)-based enzymatic biofuel cell (EBFC) has the high maximum power density (1011.21 μWcm-2), which is a 385-fold increase over that of native GOx-based EBFC (2.62 μWcm-2). This study suggests that novel enzyme nanocapsule with electroactive polymeric shell might provide a prospective solution for the performance improvement of enzymatic bioelectrocatalysis-based biodevices.
摘要:
基于酶促生物电催化的生物装置的潜在应用受到稳定性和电化学性能差的限制。为了解决限制,用功能性聚合物修饰酶以定制酶功能是非常理想的。在这里,选择葡萄糖氧化酶(GOx)作为模型酶,根据GOx辅因子(黄素腺嘌呤二核苷酸,FAD),我们为GOx定制含乙烯基的仿生辅因子(SFAD),通过原位聚合制备GOx纳米胶囊。粒度分布的表征,TEM,荧光和电化学性能表明成功形成了具有含SFAD的聚合物网络(n(GOx-SFAD-PAM))的电活性GOx纳米胶囊。该网络可以充当电子“高速公路”,将活动站点与电极连接起来,具有加速电子转移的能力以及增强的GOx稳定性。对生物电催化的进一步研究表明,基于n(GOx-SFAD-PAM)的生物传感器具有低检测电位(-0.4vs.Ag/AgCl),高灵敏度(64.97μAMM-1cm-2),良好的抗干扰性能,快速响应(35s)和出色的稳定性,n(GOx-SFAD-PAM)为基础的酶生物燃料电池(EBFC)具有较高的最大功率密度(1011.21μWcm-2),这比天然的基于GOx的EBFC(2.62μWcm-2)增加了385倍。这项研究表明,具有电活性聚合物壳的新型酶纳米胶囊可能为基于酶的生物电催化的生物装置的性能改善提供了一种有前景的解决方案。