Araque Elena, Villalonga Reynaldo, Gamella María, Martínez-Ruiz Paloma, Reviejo Julio, Pingarrón José M
Department of Analytical Chemistry, Faculty of Chemistry, Complutense University of Madrid, 28040-Madrid, Spain.
J Mater Chem B. 2013 May 7;1(17):2289-2296. doi: 10.1039/c3tb20078g. Epub 2013 Mar 22.
Reduced graphene nanoparticles were prepared from graphene oxide through a two-step covalent modification approach. Graphene oxide was first enriched with reactive epoxy groups by anchoring (3-glycidyloxypropyl)trimethoxysilane at the hydroxyl groups located on the nanocarbon basal plane. Modified graphene oxide was further cross-linked and partially reduced by treatment with the fourth-generation ethylenediamine core polyamidoamine G-4 dendrimer producing graphene nanoparticles with crumpled paper-like morphology. This graphene derivative was employed as a coating material for glassy carbon electrodes and the nanostructured electrode was tested for the preparation of electrochemical biosensors by immobilizing the enzyme tyrosinase through cross-linking with glutaraldehyde. This bioelectrode showed excellent electroanalytical behavior for catechol with a fast response in about 6 s, linear range of 10 nM to 22 μM, sensitivity of 424 mA M, and low detection limit of 6 nM. The enzyme biosensor also showed high stability when stored at 4 °C under dry and wet conditions.
还原氧化石墨烯纳米颗粒是通过两步共价修饰法由氧化石墨烯制备而成。首先，通过将（3-缩水甘油氧基丙基）三甲氧基硅烷锚定在位于纳米碳基面的羟基上，使氧化石墨烯富含反应性环氧基团而得以富集。经修饰的氧化石墨烯通过用第四代乙二胺核心聚酰胺-胺G-4树枝状大分子处理进一步交联并部分还原，从而生成具有皱纸状形态的石墨烯纳米颗粒。这种石墨烯衍生物被用作玻碳电极的涂层材料，并且通过与戊二醛交联固定酶酪氨酸酶，对这种纳米结构电极进行电化学生物传感器制备测试。该生物电极对儿茶酚表现出优异的电分析行为，响应迅速，约6秒，线性范围为10 nM至22 μM，灵敏度为424 mA M，检测限低至6 nM。该酶生物传感器在4°C干湿条件下储存时也表现出高稳定性。
