Layer-by-layer assembly of functionalized reduced graphene oxide for direct electrochemistry and glucose detection

Autor(es)

Tavares Mascagni, Daniela Branco ; Miyazaki, Celina Massumi ; da Cruz, Nilson Cristino ; de Moraes, Marli Leite ; Riul, Jr., Antonio ; Ferreira, Marystela

• Tipo de documento: Artigo Científico
• Fonte: Materials Science & Engineering C-Materials for Biological Applications; v. 68, p. 739-745, NOV 1 2016.
• Citações Web of Science: 14

Resumo

We report an electrochemical glucose biosensor made with layer-by-layer (LbL) films of functionalized reduced graphene oxide (rGO) and glucose oxidase (GOx). The LbL assembly using positively and negatively charged rGO multilayers represents a simple approach to develop enzymatic biosensors. The electron transport properties of graphene were combined with the specificity provided by the enzyme. rGO was obtained and functionalized using chemical methods, being positively charged with poly(diallyldimethylammonium chloride) to form GPDDA, and negatively charged with poly(styrene sulfonate) to form GPSS. Stable aqueous dispersions of GPDDA and GPSS are easily obtained, enabling the growth of LbL films on various solid supports. The use of graphene in the immobilization of GOx promoted Direct Electron Transfer, which was evaluated by Cyclic Volt-ammetry. Amperometric measurements indicated a detection limit of 13.4 mu mol.L-1 and sensitivity of 2.47 mu A.cm(-2). mmol(-1).L for glucose with the (GPDDA/GPSS)(1)/(GPDDA/GOx)(2) architecture, whose thickness was 19.80 +/- 0.28 nm, as determined by Surface Plasmon Resonance (SPR). The sensor may be useful for clinical analysis since glucose could be detected even in the presence of typical interfering agents and in real samples of a lactose-free milk and an electrolyte solution to prevent dehydration. (C) 2016 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 14/15093-7 - Estudos de sistemas nanoestruturados por ressonância plasmônica de superfície (SPR): aplicações em biossensoriamento
• Beneficiário: Celina Massumi Miyazaki
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 14/17519-1 - Imobilização de nanopartículas metálicas em filmes ultrafinos visando ao biossensoriamento
• Beneficiário: Marystela Ferreira
• Modalidade de apoio: Auxílio à Pesquisa - Regular