| dc.description.abstract | Superhydrophilic zwitterionic materials are recognized as a new class of antifouling materials as an alternative to poly(ethylene glycol) (PEG) for uses of biomedical device in complex conditions. In this study, we aim to develop establish a new grafting method based on polydopamine via Michael addition approach to avoid nonspecific adsorption. The developed coatings exhibit multiple functions, including 1. superhydrophilicity, 2. antifouling properties, 3. substrate-independent modification, 4. facile preparation, and 5. versatility. Dopamine contains both amine and catechol functional groups, which enables to deposit on all kinds of substrates. Sulfobetaine acrylamide (SBAA), Sulfobetaine methacrylate (SBMA) are zwitterionic monomer, which have been demonstrated with their excellent antifouling properties in a polymer brush form. Therefore, the purpose of this work is to graft SB moieties onto polydopamine (pDA) coatings containing abundant amine groups to react with vinyl groups of monomers via the Michael addition to achieve substrate-independent surface modification. We employed three monomers, i.e. SBAA, SBMA, and poly(ethylene glycol) methacrylate (PEGMA) to react with pDA. To develop an antifouling coating, an appropriate preparation strategy is highly determinant for the sufficient grafting density of fouling-resistant groups, i.e. SB and PEG. Surface characterization techniques with the contact angle goniometer, and X-ray photoelectron spectroscopy (XPS) were utilized to explore the surface hydration, chemical states and bonding mechanism of the grafted pDA films. To examine the antifouling properties of the coatings, they were brought to contact with bacteria solutions containing P. aeruginosa, E. coli, and S. epidermidis followed by observing under fluorescence optical microscope. The results indicated that the fouling levels were determined by the grafting densities of monomers on pDA surfaces. In XPS result, pDA18 coating condition grafting densities of monomer is higher than pDA3 coating condition. In pDA18 SBAA coating condition, the contact angle is less than 5 degree. According to the bacterial anti-fouling results, pDA18 SBAA coating can resistance 93%, 94.2% and 98% of P. aeruginosa, E. coli, and S. epidermidis, respectively. This can be modulated by the reaction activities of methacrylate and acrylamide with amine groups on pDA. In addition, silver particles formed in the pDA layers were applied to kill 98% adsorbed bacteria, enabling multiple functions of adlayers. The work paves a new avenue to developing the new functional bioinspired antifouling interface in a substrate-independent fashion. | en_US |