Gold microwires based amperometric biosensor exploiting microbial architecture

Amalgamation of nanotechnology and biology has opened new horizons for controlled synthesis of nanomaterials of nano and micro-lengthscales for diverse sensing, catalytic and electromechanical applications. Inspired from nature and driven by the need to have nanostructures of desired morphology, microbial architecture has been exploited as a template in the present work. Biocompatible 1-D gold microwires, generated by assembly of amino acid functionalized AuNPs over the proliferating fungal hyphae, served as potential microelectrodes for electron transfer between enzyme and electrode surface. Delocalization of electrons over longer length scales, large surface area provided by assembled AuNPs and high biocompatibility yielded excellent analytical performance characteristics with high sensitivity of 43.2 µA/mM/cm2 with standard deviation of 0.88% and wide linear range from 5 µM to 20 mM of glucose. The gold microwires thus generated demonstrate appreciable repeatability over 20 cycles in a cyclic voltammogram, and reproducibility with root mean square deviation as low as 1.3%. High stability and biocompatibility attribute these microwires with myriad potential biosensing and catalytic applications in varied domains.