Nanotechnology and Advanced Materials (NATAM), Faculty of Engineering, University of Nottingham Malaysia Campus, 43500 Semenyih, Selangor, Malaysia.
School of Chemistry, University of Melbourne, VIC 3010, Australia.
Biosens Bioelectron. 2017 Jan 15;87:622-629. doi: 10.1016/j.bios.2016.09.003. Epub 2016 Sep 1.
In this study, a sonochemical approach was utilised for the development of graphene-gold (G-Au) nanocomposite. Through the sonochemical method, simultaneous exfoliation of graphite and the reduction of gold chloride occurs to produce highly crystalline G-Au nanocomposite. The in situ growth of gold nanoparticles (AuNPs) took place on the surface of exfoliated few-layer graphene sheets. The G-Au nanocomposite was characterised by UV-vis, XRD, FTIR, TEM, XPS and Raman spectroscopy techniques. This G-Au nanocomposite was used to modify glassy carbon electrode (GCE) to fabricate an electrochemical sensor for the selective detection of nitric oxide (NO), a critical cancer biomarker. G-Au modified GCE exhibited an enhanced electrocatalytic response towards the oxidation of NO as compared to other control electrodes. The electrochemical detection of NO was investigated by linear sweep voltammetry analysis, utilising the G-Au modified GCE in a linear range of 10-5000μM which exhibited a limit of detection of 0.04μM (S/N=3). Furthermore, this enzyme-free G-Au/GCE exhibited an excellent selectivity towards NO in the presence of interferences. The synergistic effect of graphene and AuNPs, which facilitated exceptional electron-transfer processes between the electrolyte and the GCE thereby improving the sensing performance of the fabricated G-Au modified electrode with stable and reproducible responses. This G-Au nanocomposite introduces a new electrode material in the sensitive and selective detection of NO, a prominent biomarker of cancer.
在本研究中，采用超声化学法制备了石墨烯-金（G-Au）纳米复合材料。通过超声化学法，同时实现了石墨的剥离和氯化金的还原，生成了高结晶度的 G-Au 纳米复合材料。金纳米粒子（AuNPs）在剥离的少层石墨烯片表面原位生长。采用紫外可见光谱、XRD、FTIR、TEM、XPS 和拉曼光谱技术对 G-Au 纳米复合材料进行了表征。该 G-Au 纳米复合材料被用于修饰玻碳电极（GCE），以制备用于选择性检测一氧化氮（NO）的电化学传感器，NO 是一种重要的癌症生物标志物。与其他对照电极相比，G-Au 修饰的 GCE 对 NO 的氧化表现出增强的电催化响应。通过线性扫描伏安法分析研究了 NO 的电化学检测，利用 G-Au 修饰的 GCE 在 10-5000μM 的线性范围内，检测限为 0.04μM（S/N=3）。此外，在存在干扰物的情况下，这种无酶 G-Au/GCE 对 NO 表现出优异的选择性。石墨烯和 AuNPs 的协同效应促进了电解质和 GCE 之间的异常电子转移过程，从而提高了所制备的 G-Au 修饰电极的传感性能，具有稳定和可重复的响应。该 G-Au 纳米复合材料为敏感和选择性检测 NO 提供了一种新的电极材料，NO 是癌症的一个重要生物标志物。
