An intravenous implantable glucose/dioxygen biofuel cell with modified flexible carbon fiber electrodes

• Published in: Lab on a chip 2013-02, Vol.13 (3), p.468-474
• Main Authors: Sales, Fernanda C P F, Iost, Rodrigo M, Martins, Marccus V A, Almeida, Maria C, Crespilho, Frank N
• Format: Article
• Language: English
• Subjects: Animals; Bioelectric Energy Sources; Carbon; Dendrimers - chemistry; Electrodes; Equipment Design; Glucose - chemistry; Glucose Oxidase - metabolism; Male; Nanoparticles - chemistry; Nylons - chemistry; Oxidation-Reduction; Oxygen - chemistry; Rats; Rats, Wistar; Rattus
• ISSN: 1473-0197; 1473-0189
• DOI: 10.1039/c2lc41007a

An intravenous implantable glucose/dioxygen hybrid enzyme-Pt micro-biofuel cell (BFC) was investigated. In this miniaturized BFC, a flexible carbon fiber (FCF) microelectrode modified with neutral red redox mediator and glucose oxidase was used as the bioanode, and an FCF modified with platinum nanoparticles stabilized on PAMAM-G4 dendrimer was used as the cathode. In vitro experiments conducted using the BFC in a phosphate buffer solution (50 mmol L(-1), pH = 7.2) and glucose (47 mmol L(-1)) showed high electrocatalytic performance with an open circuit voltage (OCV) of 400 mV, a maximum current density of 2700 μA cm(-2) at 0.0 V and a maximum output power of 200 μW cm(-2) at 250 mV. Under physiological conditions, glucose from rat blood is used as a fuel in anodic reactions and dissolved molecular oxygen is used as the oxidizing agent on the cathode. For in vivo experiments, the BFC was inserted into the jugular vein of a living rat (Rattus novergicus) using a catheter (internal diameter 0.5 mm). The power density of the implantable BFC was evaluated over a period of 24 h, and an OCV of 125 mV with a maximum power density of 95 μW cm(-2) was obtained at 80 mV.