title: Redox-active thionine-graphene oxide hybrid nanosheet: one-pot, rapid synthesis, and application as a sensing platform for uric acid.
abstract: In this paper, we fabricate a sensitive and stable amperometric UA amperometric biosensor using nanobiocomposite derived from thionine modified graphene oxide in this study. A simple wet-chemical strategy for synthesis of thionine-graphene oxide hybrid nanosheets (T-GOs) through π-π stacking has been demonstrated. Various techniques, such as UV-vis absorption spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), atomic force microscopy (AFM) and electrochemistry have been utilized to characterize the formation of the T-GOs. Due to the synergistic effect between thionine and graphene oxide, the nanosheets exhibited excellent performance toward H(2)O(2) reduction. The incorporation of thionine onto graphene oxide surface resulted in more than a twice increase in the amperometric response to H(2)O(2) of the thionine modified electrode. The as-formed T-GOs also served as a biocompatible matrix for enzyme assembly and a mediator to facilitate the electron transfer between the enzyme and the electrode. Using UOx as a model system, we have developed a simple and effective sensing platform for assay of uric acid at physiological levels. UA has been successfully detected at -0.1 V without any interference due to other electroactive compounds at physiological levels of glucose (5 mM), ascorbic acid (0.1 mM), noradrenalin (0.1 mM), and dopamine (0.1 mM). The response displays a good linear range from 0.02 to 4.5 mM with detection limit 7 μM. The application of this modified electrode in blood and urine UA exhibited a good performance. The robust and advanced hybrid materials might hold great promise in biosensing, energy conversion, and biomedical and electronic systems.
authors: Key Laboratory of Resources Chemistry of Nonferrous Metals, Ministry of Education, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, Hunan, People's Republic of China.
authors: Zhoumin
authors: Z
authors: Sun
authors: Haiying
authors: H
authors: Fu
authors: Liu
authors: L
authors: Deng
authors: Jianxiu
authors: J
authors: Wang
mesh_terms: D055664:Electrochemical Techniques / Q000379:methods*; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D057230:Limit of Detection; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D010640:Phenothiazines / Q000737:chemistry*; D014527:Uric Acid / Q000032:analysis / Q000097:blood* / Q000652:urine*
chemical_list: D010087:Oxides; D010640:Phenothiazines; D014527:Uric Acid; D006108:Graphite; D006861:Hydrogen Peroxide; C009469:thionine