A facile synthesis of polydopamine/TiO2 composite films for cell sheet harvest application

This study presents a convenient and versatile way to prepare functionalized composite polydopamine/titanium dioxide (PDA/TiO 2 ) film on polystyrene (PS). First, polystyrene substrate was immersed in dopamine chloride solution, and then collosol containing TiO 2 and water was spun on it, to produce uniform, continuous PDA/TiO 2 composite films. The thickness of film was controllable by adjustment of the spin speed. It was found that the films were strongly adhered on the PS substrate, with peel strength and shear strength of 2.78 MPa and 37.78 MPa, respectively. After 20 min of ultraviolet (365 nm) illumination, over 90% of fibroblasts and 77% of osteoblasts detached from the PDA/TiO 2 composite film. Additionally, the detached cells showed good viability, allowing further culture and applications. This preparation method could be widely applied for cell and cell sheet harvesting directly from PS-based culture wares.