Biocatalytic growth of gold agglomerates on an electrode for aptamer-based electrochemical detection

Here we describe the biocatalytic growth of high-density gold agglomerates on a gold electrode surface to form a carrier for aptamer probe immobilization. The present approach provides a simple strategy to promote the seed-mediated deposition of Au from AuCl(4)(-) onto surface-attached 12 nm diameter Au nanoparticles (AuNPs) in the presence of reductive coenzyme and surfactant. The growth process was studied by electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM). This nanostructured platform is effective and prospective toward the aptamer probe immobilization. For the nice performance of enhanced substrate, the aptamer-sensing interface showed excellent applicability under the investigations such as alternating current voltammetry (ACV) and surface-enhanced Resonance Raman scattering (SERRS) spectra.