Improving Photovoltaic and Enzymatic Sensing Performance by Coupling a Core-Shell Au Nanorod@TiO2 Heterostructure with the Bioinspired L-DOPA Polymer
Improving Photovoltaic and Enzymatic Sensing Performance by Coupling a Core-Shell Au Nanorod@TiO2 Heterostructure with the Bioinspired L-DOPA Polymer
复制标题
通过将核壳金纳米棒@TiO2异质结构与仿生L-DOPA聚合物耦合来提高光伏和酶传感性能
DOI：
10.1021/acsami.8b19284
复制
发表时间：
2019-03-06
影响因子：
9.5
通讯作者：
Xie, Qingji
中科院分区：
文献类型：
--
作者：
Wang, Linping;Meng, Yue;Xie, Qingji
TiO 2的光电化学（PEC）性能受到其宽带隙和低量子效率的限制，其复合材料的创新为改善性能提供了有前途的解决方案。本文设计并制备了Au纳米棒@ TiO 2核壳结构（AuNR @ TiO 2）和类黑色素L-DOPA聚合物（PD）的复合物，其中外层PD通过TiO 2-羟基络合物与AuNR核的束缚作用可以增强长波长光的捕获，AuNR @ TiO 2核壳结构可以增强热电子向TiO 2的转移。PD/AuNR@TiO2的光电流比市售TiO 2提高了8.4倍，在紫外-可见-近红外区最大入射光电转换效率达到65%。此外，新型PD/AuNR@TiO2光催化剂具有良好的生物相容性和稳定性，可作为多功能PEC生物传感平台，提供生物相容性环境，提高检测灵敏度。本文基于葡萄糖氧化酶（GOx）和辣根过氧化物酶（HRP）双酶在PD中的固定化和生物催化沉淀的信号转导策略，研制了葡萄糖PEC酶传感器。在含有葡萄糖和4-氯-1-萘酚的磷酸盐缓冲液中，GOx产生的H2 O2在HRP催化下氧化4-氯-1-萘酚，会在电极上形成沉淀，光电流强度的衰减与葡萄糖浓度的常用对数成正比。线性检测范围为0.05 μ M至10.0 mM葡萄糖，检测限为0.01 μ M（S/N = 3）。测定了人血清中的葡萄糖，结果令人满意。
The photoelectrochemistry (PEC) performance of TiO2 is somewhat limited by its wide band gap and low quantum efficiency, and the innovation of its composite materials provides a promising solution for an improved performance. Herein, a composite of a Au nanorod@TiO2 core-shell nanostructure (AuNR@TiO2) and a melanin-like L-DOPA polymer (PD) is designed and prepared, where the outer layer PD tethered by TiO2-hydroxyl complexation and the AuNR core can intensify the long-wavelength light harvesting, and the AuNR@TiO2 core-shell structure can strengthen the hot-electron transfer to TiO2. The photocurrent of PD/AuNR@TiO2 is 8.4-fold improved versus that of commercial TiO2, and the maximum incident photon-to-electron conversion efficiency reaches 65% in the UV-visible-near-infrared region. In addition, the novel PD/AuNR@TiO2 photocatalyst possesses the advantages of good biocompatibility and stability, which can act as a versatile PEC biosensing platform for providing a biocompatible environment and improving detection sensitivity. Herein, a PEC enzymatic biosensor of glucose is developed on the basis of the immobilization of dual enzyme [glucose oxidase (GOx) and horseradish peroxidase (HRP)] in PD and the signaling strategy of biocatalytic precipitation. In phosphate buffer containing glucose and 4-chloro-1-naphthol, the HRP-catalyzed oxidation of 4-chloro-1-naphthol by GOx-generated H2O2 can form a precipitate on the electrode, by which the decrement of photocurrent intensity is proportional to the common logarithm of glucose concentration. The linear detection range is from 0.05 mu M to 10.0 mM glucose, with a limit of detection of 0.01 mu M (S/N = 3). Glucose in some human serum samples is analyzed with satisfactory results.