Tunable Assembly of Photocatalytic Colloidal Coatings for Antibacterial Applications.

In this study, evaporation-induced size segregation and interparticle interactions are harnessed to tune the microstructure of photocatalytic colloidal coatings containing TiO nanoparticles and polymer particles. This enabled the fabrication of a library of five distinct microstructures: TiO-on-top stratification, a thin top layer of polymer or TiO, homogeneous films of raspberry particles, and a sandwich structure. The photocatalytic and antibacterial activities of the coatings were evaluated by testing the viability of Methicillin-resistant (MRSA) bacteria using the ISO-27447 protocol, showing a strong correlation with the microstructure.