Thyroxine incorporated commercially available alginate dressings to stimulate angiogenesis for wound healing applications

Advanced wound care products had attracted great attention and particularly materials stimulating angiogenesis is one of the major focussed area. The identification of suitable angiogenic agents and then delivery from a well accepted carrier materials, ideally the one being already in clinical use is well adopted approach. Alginate dressings are very well accepted dressings worldwide in clinic and in present work alginate dressings were modified to support angiogenesis by loading thyroxine. To study the affect of concentration of thyroxine, 1 μg/ml, 5 μg/ml and 10 μg/ml thyroxine was loaded into alginate dressings. Any chemical changes in the dressings after loading thyroxine was studied by FTIR analyses and it was found that loading of thyroxine did not produce any chemical change in alginate dressings. The sustained thyroxine release up to 74% was observed in the phosphate buffer pH 7.4 over seven days time. The cytotoxicity study was conducted using fibroblasts cells and all thyroxine concentrations were found to be biocompatible and assisted cells proliferation. Real time PCR was used to evaluate the gene expression of fibroblasts treated with synthesized alginate hydrogels to evaluate the effect of thyroxine on genes involves in angiogenic pathway. To study angiogenic activity chorioallantoic membrane (CAM) assay was performed, it was observed higher number of new junctions, angiogenic potential was shown by 5 μg/ml thyroxine loaded alginate dressings. These results suggested that the thyroxine loaded alginate dressings have very high potential of fast wound healing.