This Is AuburnElectronic Theses and Dissertations

Synthesis and Characterization of Photopolymerizable Hydrogels for Biomedical Applications

Date

2020-07-22

Author

Joshi, Prutha

Type of Degree

PhD Dissertation

Department

Chemical Engineering

Abstract

Hydrogels are polymeric materials widely used in medicine due to their similarity with the biological components of the body. These biocompatible materials have the potential to promote cell proliferation and tissue support because of their hydrophilic nature, porous structure, and elastic properties. The hydrophilicity, mechanical properties and cell responsivity of modified polysaccharides can be tuned by controlling the chemical and molecular structure for different tissue engineering applications. The results show that there is a range of elastic modulus and degradation rate of hydrogels, which can be targeted for various biomedical applications. In chapter two, we focused on the synthesis of different varieties of poly(ethylene glycol) dimethacrylate (PEGDMA) formulated from poly(ethylene glycol) (PEG) of different molecular weights and further photocured in the presence of a photoinitiator (Irgacure 184). Chemical, thermal, mechanical, rheological, and morphological characteristics were studied, as well as biodegradability. The ability of these hydrogels as material for cell growth was investigated for application towards tissue engineering. In chapter three, the focus was on the incorporation of methacrylate functionality in gelatin and chitosan polysaccharides. The modified gelatin and chitosan were synthesized by controlling the degree of methacrylation of primary amine groups present in polysaccharides. Further, the effects of various varieties of hydrogels on swelling, mechanical, and rheological properties were investigated. The hydrogels were prepared by UV photocuring of modified polysaccharides in the presence of a photoinitiator Irgacure 184 (365nm wavelength). In chapter four, we combine the properties of poly(ethylene glycol) dimethacrylate (PEGDMA) macromer and polysaccharides in double networks (DN) for synergistic effects of unique properties of both components resulting in the interpenetrating polymeric network for making it functional for replacement of injured tissues inside the human body. In the final chapter, the research is based on how the synthesized hydrogels can also be 3D printed to obtain cellular structures for tissue engineering applications. The stereolithography (SLA) 3D printing was carried out with the macromer and double network of macromer systems to get variety in properties of the hydrogel to make it a complex-structured scaffold for tissue engineering. Altogether, the biomaterial hydrogel properties open the way for applications in the field of medicine.