The use of SF6 plasma-nanotextured poly(dimethylsiloxane) (PDMS) substrates of columnarlike surface topography as templates for protein adsorption is presented. Fresh and aged plasma-nanostructured surfaces are investigated, since ageing affects surface wettability, a critical parameter in protein adsorption. It is found that protein adsorption on such substrates increases with plasma treatment duration and surface ageing. An enhancement (up to ten times) in adsorption of biotinylated bovine serum albumin is observed on aged nanostructured PDMS substrates compared to untreated ones. Good spot homogeneity is obtained on surfaces treated for up to 6 min. The use of optimized plasma-nanostructured surfaces as substrates for protein microarrays of intense and uniform spots is demonstrated.