Enhanced Wound Healing by Nanoengineered Hydrogel Patch Loaded with Connective Tissue Growth Factor

Impaired wound healing is a challenging diabetic complication associated with substantial mortality and morbidity. Lack of limited cell proliferation, and poor cell-cell communication, are leading causes of delayed wound healing. To address this problem, connective tissue growth factor (CTGF), an important factor contributing to wound healing, was employed. In addition, reduced graphene oxide nanoparticles (rGO) were found to promote wound healing by enhancing the proliferation and migration of the cells. Therefore, CTGF conjugated rGO-loaded gelatin methacryloyl (GelMA) patch was investigated for treating experimental wounds in mice. Scanning Electron Microscopy (SEM) showed porous structure of the patches, and Fourier transform infrared spectroscopy (FTIR) confirmed the conjugation of CTGF onto rGO. The developed patches also exhibited excellent water-absorbing ability (700% water intake in the first 15minutes) and biodegradability (40% degradation in 28 days) in phosphate-buffered solution (PBS). Three different cell lines (HaCaT keratinocytes, EA.hy926 endothelial cells, and 3T3 fibroblasts) investigated different concentrations of rGO/CTGF. In vitro cell culture studies showed that the cells possess improvement in proliferation and viability upon culturing with hydrogel patches containing rGO/CTGF conjugates. GelMA patch containing 0.006% (w/w) rGO & 0.00006% (w/w) CTGF (GCR6), significantly increased the migration ability of tested cells. Furthermore, there was 98.3% wound closure of mice dorsal skin wounds, upon treatment of GCR6 for 21 days, compared to the negative control (78% wound closure). Owing to the higher wound healing potential, the developed patches loaded with CTGF conjugated rGO provide a new and effective therapeutic method for developing novel wound dressing suitable for clinical application.