title: Bio-inspired multifunctional catecholic assembly for photo-programmable biointerface.
abstract: This article reports a novel multifunctional mussel-inspired zwitterionic catecholic assembly to form a photoresponsive biointerface. The assembly is the combination of the antifouling sulfobetaine and photocleavable o-nitrophenyl moieties into a molecule, becoming sulfobetaine nitrodopamine (SB-nDA). We demonstrated the formation of a compact thin SB-nDA film on TiO₂ by using the pH transition approach. The film thickness, surface wettability and elemental composition were characterized using ellipsometry, contact angle goniometer, atomic force microscopy and X-ray photoelectron spectroscopy, respectively. The SB-nDA thin films can effectively resist adhesion of both Gram-positive Staphylococcus epidermidis and Gram-negative Pseudomonas aeruginosa by more than 95% relative to bare TiO₂. Quartz crystal microbalance with dissipation (QCM-D) sensor was employed for protein fouling tests, showing the comparable antifouling property of SB-nDA with thiol- or silane-based surface ligands. More importantly, the spatiotemporal control over the bioinertness by UV irradiation has been studied with bacterial and protein adsorption. Therefore, the catecholic chemistry can be used for programmable tailoring of interfacial properties, permitting potential application in light-guided targeting for nanomedicine.
authors.affiliation: Graduate Institute of Biomedical Engineering, National Central University, Jhong-Li, Taoyuan 320, Taiwan; Chemical & Materials Engineering Department, National Central University, Jhong-Li, Taoyuan 320, Taiwan. Electronic address: cjhuang@ncu.edu.tw.
authors.forename: Chun-Jen
authors.initials: CJ
authors.lastname: Huang
authors.affiliation: Graduate Institute of Biomedical Engineering, National Central University, Jhong-Li, Taoyuan 320, Taiwan.
authors.forename: Lin-Chuan
authors.initials: LC
authors.lastname: Wang
mesh_terms: D001422:Bacterial Adhesion; D002396:Catechols / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D010777:Photochemistry; D056951:Photoelectron Spectroscopy; D011550:Pseudomonas aeruginosa / Q000502:physiology; D058525:Quartz Crystal Microbalance Techniques; D013212:Staphylococcus epidermidis / Q000502:physiology
chemical_list: D002396:Catechols
keywords: Bio-inspired materials; Biointerfaces; Catecholic chemistry; Self-assembled monolayers; Zwitterionic materials