Hydrogel Design And Property Study For Treating Ophthalmic Diseases

The eye is an important organ for maintaining vision,but ophthalmic diseases have become problems that plagued people for many years,including vitreous disease and corneal damage.In this work,aiming at these two ophthalmic diseases,two kinds of hydrogels were designed and constructed,and their properties were studied.Vitreous replacement is a crucial method to treat intraocular vitreous diseases.In this study,a carboxybetaine-type zwitterionic polymer poly(2-((2-acrylate-3-(methacryloyloxy)propyl)dimethylammonio)acetate)(PCB-OAA)was designed and synthesized,and crosslinked with dithiothreitol(DTT)to form PCB-OAA hydrogel.The nuclear magnetic resonance spectrum proved the successful synthesis of the polymer.The functional group conversion rate test showed that the gelation process was high-efficient.In addition,the PCB-OAA hydrogel exhibited approximate density,refractive index,light transmittance,storage modulus,and viscoelastic properties to those of natural vitreous.The biological antifouling performance results demonstrated that this hydrogel could effectively inhibit the adhesion of proteins and cells.The PCB-OAA hydrogel was injected into the vitreous cavity of rabbits by insitu gelling.Ocular examinations for six months revealed that the hydrogel had excellent biocompatibility in vitreous cavity.Therefore,this zwitterionic polymer hydrogel holds great potential as a vitreous substitute.In order to treat corneal injury,polyethylene glycol diacrylate(PEGDA)/gelatin methacrylate(GelMA)hydrogel was synthesized and developed as an ink.The PEGDA/GelMA ink loading rabbit corneal epithelial cells was 3D printed into corneal scaffolds.The results show that the printed cell-loaded hydrogel had sufficient mechanical properties,high light transmittance and shape fidelity.The scaffold had suitable swelling degree and degradation rate.In addition,the hydrogel exhibited excellent cytocompatibility and could support cell adhesion,proliferation and migration.The cells in hydrogel showed a high survival rate during printing process.Therefore,this 3D-printed cell-loaded hydrogel scaffold is promising to be applied for corneal regeneration and repair.