Verma Shilpi, Arya Priyanshu, Singh Anu, Kaswan Jyoti, Shukla Ajay, Kushwaha Hemant R, Gupta Shalini, Singh Surinder P
Academy of Scientific and Innovative Research (AcSIR), CSIR-HRDC Campus, Ghaziabad, Uttar Pradesh, 201002, India; CSIR-National Physical Laboratory, Dr. K. S. Krishnan Road, New Delhi, 110012, India.
Dept of Chemical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India.
Biosens Bioelectron. 2020 Oct 1;165:112347. doi: 10.1016/j.bios.2020.112347. Epub 2020 Jun 5.
We present a tyrosinase-conjugated zinc oxide-reduced graphene oxide (Tyr/ZnO-rGO) nanocomposite system as a biosensing test-bed for rapid and sensitive detection of dopamine (DA). The bioelectrodes (Tyr/ZnO-rGO/ITO) were designed by covalently immobilizing tyrosinase enzyme on spin-coated films of ZnO-rGO nanocomposite prepared via self-assembly approach. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) showed fast electron transfer kinetics of ZnO-rGO/ITO electrode. The response studies of the Tyr/ZnO-rGO/ITO bioelectrode revealed ultrafast (0.34 ± 0.09 s) detection of DA in a wide linear dynamic range of 0.1-1500 pM. The significant performance of the biosensor in terms of low detection limit (8.75 ± 0.64 pM) and high sensitivity (39.56 ± 0.41 μA nM) values is attributed to the fast and unhindered electron transfer mechanism of ZnO-rGO matrix having low electrochemical band gap. The nanoplatform exhibited high selectivity toward DA in human sera, and remained stable up to 3 months at 4 °C, representing its suitability for clinical applications.
我们展示了一种酪氨酸酶共轭的氧化锌-还原氧化石墨烯（Tyr/ZnO-rGO）纳米复合体系，作为用于快速灵敏检测多巴胺（DA）的生物传感测试平台。通过将酪氨酸酶共价固定在通过自组装方法制备的ZnO-rGO纳米复合自旋涂层薄膜上，设计了生物电极（Tyr/ZnO-rGO/ITO）。循环伏安法（CV）和电化学阻抗谱（EIS）表明ZnO-rGO/ITO电极具有快速电子转移动力学。Tyr/ZnO-rGO/ITO生物电极的响应研究表明，在0.1 - 1500 pM的宽线性动态范围内，能够超快（0.34±0.09秒）检测DA。该生物传感器在低检测限（8.75±0.64 pM）和高灵敏度（39.56±0.41μA nM）方面的显著性能归因于具有低电化学带隙的ZnO-rGO基质的快速且无阻碍的电子转移机制。该纳米平台对人血清中的DA表现出高选择性，并在4°C下长达3个月保持稳定，表明其适用于临床应用。
