In a prior study conducted by our group, the remarkable efficacy of vertical arrays of silicon nanopillars (SiNPs) for the rapid separation and sensing of target proteins from complex bio-samples was demonstrated . The SiNPs platform was created via metal-assisted chemical etching (MACE), to create a stable nanostructured surface directly from a silicon wafer. MACE is a simple and low-cost method for fabricating Si nanostructures with the ability to control their shape, diameter, length, and nanostructure orientation relative to the substrate . The SiNPs provides several advantageous features as a sensing area for biosensing applications and especially immunosensors. For example, a high surface area-to-volume ratio renders them highly sensitive to changes in the local environment, a crucial characteristic for detecting small amounts of analytes and enhancing the resulting signal .