Fabrication of Nanostructured Polymeric Surfaces for Biosensing Devices

In this paper a method for fabricating nanostructured polymeric surfaces with contrasted chemical functionality is presented. First, a polymer film of acrylic acid (PAA) is deposited by plasma enhanced chemical vapor deposition. It is covered by a monolayer of particles in the 500 nm range. Then oxygen plasma etching is performed, providing etching of both nanoparticles and acrylic acid film present between the masks. The etching process is stopped before the complete etching of the nanoparticles and the residual ones are removed by ultrasonic bath. Chemical contrast is thus created between nanodomes having plateau-like surface with as-deposited carboxylic functionality and substrate surface. Protein attachment experiments show that proteins are selectively bound to the functional plateau of the PAA domes.