Effect of size and curvature on the enzyme activity of bionanoconjugates

Biotic-abiotic hybrids comprised of globular proteins and functional nanostructures with complementary and synergistic properties are central to a number of bionanotechnological applications. A comprehensive understanding of the effect of physicochemical properties of abiotic nanostructures on the biological activity of the bionanoconjugates is critical in the design of these bio-nano hybrids. In this study, using size and curvature-controlled gold nanoparticles as a model abiotic system, we investigated the effect of hydrodynamic diameter and surface curvature on the activity of a model enzyme, horseradish peroxidase (HRP), adsorbed on the surface of the nanostructures. In contrast with the previous studies, we have employed a novel class of gold superstructures (gold nanoparticles on spheres) to deconvolute the effects of size and curvature on the catalytic activity of the bionanoconjugates. This study improves our understanding of the bio/nano interface and the design of bioinorganic hybrids with potential applications in biomimetic and bioenabled sensors, energy harvesting, optoelectronic components and devices, responsive and autonomous materials.