A novel micropattern platform constructed by TiO₂ oxidation of PDA

Dopamine is a small molecule inspired by the dopamine motif of mussel foot proteins, and PDA is formed by the self-polymerization of dopamine. Under the UV-irradiation，PDA would be oxidized by reactive oxygen species (ROS) which were produced by photocatalytic reactions on TiO₂ surfaces，thus regulating the adhesion behavior of endothelial cells (ECs) TiO₂ inhibited platelet (Plt) adhesion after UV exposure. Polydopamine (PDA)-TiO₂ micropatterns (P-PDA-TiO₂) were prepared by magnetron sputtering and photolithography. This micropatterns successfully achieves selective adhesion of Plt and ECs. The selective adhesion of ECs disappears after vacuum reduction. In contrast to conventional cell patterning strategies, P-PDA-TiO₂ can easily achieve pattern separation of ECs and Plts and provide a new concept for building complex blood-contacting devices.