Micro-spot, UV and wetting patterning pathways for applications of biofunctional aminosilane-titanate coatings

The micropatterning of functional films for biomedical applications is a key part of the process leading to a precise application. In the present work we present three different methodologies to micro-design biofunctional aminosilane-titanate coatings. The chemical functionality of the surface immobilized amino groups was initially tested by surface characterization techniques. X-ray photoelectron spectroscopy was used to analyze the films before and after derivatization with Trifluoromethylbenzaldehyde while atomic force microscopy was used to study the adsorption kinetics onto these hybrid films. The three micropatterning pathways were selected for three different kinds of applications: (1) 300 microm spots were satisfactorily used for oligonucleotide immobilization, (2) Masked regions protected from UV irradiation were intensively coated by colloidal gold nanoparticles creating a drastic contrast with respect to the UV exposed areas, and (3) radial micro stripes, used afterwards for culturing cells, were created onto Si substrates by wetting from modified precursor solutions. The results are a clear indication of the versatility of hybrid aminosilane-titanate coatings for biomedical applications requiring micropatterned biofunctional surfaces.