Characteristics of Two Self-Powered Glucose Biosensors

Here, we describe the characterization of a self-powered glucose biosensor that is capable of generating electrical power from the biochemical energy stored in glucose to serve as the primary source of power for microelectronic devices. One self-powered glucose biosensor is based on multi-walled carbon nanotubes modified with pyroquinoline quinone glucose dehydrogenase (PQQ-GDH) and laccase at the bioanode and biocathode, respectively, whereas the other employed bilirubin oxidase at the biocathode. The self-power glucose biosensor employing the bilirubin oxidase biocathode operated at physiological condition and produced an enhanced peak power and current densities as compared with the self-powered glucose biosensor comprising of PQQ-GDH bioanode and laccase biocathode. The self-powered glucose biosensor employing bilirubin oxidase produced an average open circuit voltage of 0.480 V and delivered an average short circuit current density of 0.64 mA/cm(2) with a peak power density of 0.089 mW/cm(2). In addition, this self-powered glucose biosensor exhibited a linear dynamic range of 0.5-35 mM with a sensitivity of 12.221 Hz/mM.cm(2). The use of bilirubin oxidase as the biocathodic enzyme makes it a viable candidate as a potential power source for in vivo applications.