In a collaboration with the ‚Bioinspired materials‘ group of Oliver Strube, Paderborn University, we combine the advantages of nanosphere lithography (NSL) and enzyme mediated autodeposition (EMA) as a novel approach for bioinspired material design on prepatterned surfaces.
We create antidot structured Pt thin films on SiO2 by nanosphere lithography. Subsequent immobilization of the enzyme chymosin in the freely accessible SiO2 areas of antidots allows to induce site-specific deposition of casein particles in the nanometer scale.
Enzyme-catalyzed cleavage reactions can drastically change the solubility of dispersed biomolecules, such as casein. EMA uses this for a controlled deposition of destabilized particles in close proximity to a surface. Key factor is the tethering of enzyme onto the surface, defining the area with enzymatic activity. Limitation of enzyme activity to this reaction zone induces controlled deposition only in this area and prevents uncontrolled protein precipitation.
The size of the reaction zone can be tailored and is defined in this combined approach in all dimensions. Its lateral area is determined by NSL-formed antidots, its vertical range by enzyme coupling.
Thus, structured protein coatings with tailored morphology are created.