Thermo and light-responsive strategies of smart titanium-containing composite material surface for enhancing bacterially anti-adhesive property

Abstract

Despite adopting diverse antibacterial or superwettable surface strategies could realize their bacterial anti-adhesion and anti-biofilm, designing material surface of adjustable bacterial anti-adhesion by smart response to adapt to mutable environment is urgently needed. Herein, thermo and light-responsive strategies were adopted to adjust and enhance the bacterial anti-adhesion and render composite material surface with smart response for the complex environmental change. This composite surface was designed with light-responsive titanium dioxide nanotubes/titanium (TNTs)/Ti surface as base and grafting thermo-responsive P(vinylcaprolactam (VCL)–co-polyethylene glycol methacrylate (PEGMA)–co-alkyl-dimethyl tertiary amine (QAS)–co-vinyltrimethoxysilane (VTMO)) copolymer on, and endowed with the long-lasting antibacterial QAS and hydrophilic PEGMA constituents to greatly reduce bacterial adhesion. The bacterial anti-adhesion could be intelligently adjusted and enhanced owing to the thermo-response of VCL in the copolymer and light-response of TNTs arrays. The resisting effect of hydrated layer formed by PEGMA and its resisting enhancement by TNTs were demonstrated as important roles in bacterial anti-adhesion. An enhancement of bacterial anti-adhesion triggered by thermo-response was ascribed to the underwater conformational change of polymer molecules observed by in-situ atomic force microscopy (AFM), and that triggered by light-response was due to the generated reactive oxygen species (ROS) on the composite surface. The robust durability of antibacterial and bacterially anti-adhesive properties paved good foundations for application in the mutable environment.