Receptor arrays for the selective and efficient capturing of viral particles

We describe microarrays of receptors on gold/glass substrates for the selective capturing of viral particles at high density. Microscale gold squares were surface-modified with alkanethiol derivatives which enabled the immobilization of the His(6)-tagged virus-binding domain from the very-low density lipoprotein (VLDL) receptor. The free glass areas surrounding the gold squares were passivated with a dense film of poly(ethylene glycol) (PEG). As assessed by atomic force microscopy, human rhinovirus particles were captured onto the VLDL-receptor patches with a high surface coverage but were effectively repelled by the PEG layer, resulting in a 330 000-fold higher density of the particles on the gold as compared to the glass surfaces. The metal chelate-based coupling strategy was found to be superior to two alternative routes, which used the covalent coupling of viral particles or viral receptors to the substrate surface. The high-density receptor arrays were employed for sensing and characterizing viral particles with so far unprecedented selectivity.