Fabrication of nanopatterned films of bovine serum albumin and staphylococcal protein A using latex particle lithography

Arrays of protein nanostructures can be formed on surfaces such as mica(0001) and Au(111) using lithography with polystyrene latex particles. To create arrays of protein nanostructures, monodisperse latex spheres are mixed with the desired protein (e.g. BSA, protein A or IgG) and deposited onto substrates. Protein-coated nanospheres self-assemble into organized crystalline layers when dried on flat surfaces. After rinsing with water, dried latex spheres are displaced to expose periodic arrays of uncovered circular cavities. The immobilized proteins remain attached to the surface and form nanopatterns over broad areas (microns) corresponding to the thickness of a single layer of proteins. The nanostructures of immobilized proteins maintain the order and periodicity of the latex scaffold. The morphology and diameter of the protein nanostructures are tuneable by selecting the ratios of protein-to-latex and the diameters of latex spheres. Well-defined nanostructured surfaces of proteins supply a tool for fundamental investigations of protein binding interactions in biological systems at the nanoscale and have potential applications in biochip and biosensing systems.