Preparation of anti-adhesive and antibacterial surfaces using polymers

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2017
Onat, Bora
Layer-by-layer self-assembly of polymers is a versatile technique which can impart new functions to the surfaces of biomedical instruments and biomaterials. Materials which are coated by this technique can exhibit response towards environmental stimuli, such that the controlled release of drugs and similar biologically functional molecules under different stimuli can be observed. In the span of this thesis study, ultra-thin polymer films were prepared through the layer-by-layer self-assembly technique, the physicochemical properties of the films were assessed and their potential functions in biomedical studies which cover coating surfaces to impart anti-adhesive and antibacterial properties were discovered. As described in the first chapter of the thesis, multilayer films of zwitterionic block copolymer micelles has shown bacterial anti-adhesive and pH-responsive antibacterial agent releasing properties. The antibacterial agent was released from the pH-responsive cores of the block copolymer micelles. In the second chapter of the thesis, for the purpose of supporting the bone regeneration and reducing the time of acceptance of the implants in the body, multilayer films of antibacterial Tannic Acid (TA) and biodegradable poly(4-hydroxy-L-proline ester) (PHPE) was studied. It was determined that, these films are osteoconductive and support the regeneration of the bone. In the third chapter of the thesis, multilayer films of TA and thermoresponsive poly(N-vinyl caprolactam) (PVCL) was deposited on hydrogels composed of chitosan and polyethylene glycol (PEG). It was shown that, at physiological temperature, antibiotic release from the hydrogel membranes was enhanced. It was also determined that, hydrogels with TA and PVCL multilayer-film surface modifications enhance the viability of fibroblasts in the skin. This type of hydrogels hold promise in use as antibacterial wound dressings. Layer-by-layer self-assembly technique is a facile and versatile method of preparing biologically functional surfaces. The films which are prepared in the extent of this thesis are not only promising for bacterial anti-adhesive and antibacterial applications, but also for bone regeneration and wound healing.

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Citation Formats
B. Onat, “Preparation of anti-adhesive and antibacterial surfaces using polymers,” Ph.D. - Doctoral Program, Middle East Technical University, 2017.