Amino acids loaded chitosan/collagen based new membranes stimulate angiogenesis in chorioallantoic membrane assay

Chitosan/collagen-based hydrogels were studied for their promising role in skin tissue engineering applications due to their unique biocompatibility and biodegradation properties. Amino acids are not only the mean of protein building units but also support endothelial cells proliferation and trigger angiogenesis during wound healing. The purpose of this study was to prepare amino acid based pro-angiogenic materials. Three structurally closed amino acids (AA) (arginine, alanine and phenylalanine) were loaded into chitosan/collagen hydrogels (ACC hydrogels) to study their effect on angiogenesis. In this study the ACC hydrogels were prepared through freeze drying procedure and their angiogenic potential was studied by chorioallantoic membrane assay (CAM assay). FTIR analysis was performed to confirm that there was no chemical change took place in polymeric materials during synthesis procedures. Results revealed that, arginine-loaded hydrogels were the most porous, with more interconnected pores and also the maximum growth of blood vessels were found around and inside the arginine loaded scaffold. The qualitative analysis for blood vessels showed the significant difference between control, chitosan/collagen alanine loaded hydrogel (CH-Ala), chitosan/collagen phenylalanine loaded hydrogel (CH-Phe) and chitosan/collagen arginine loaded hydrogel (CH-Arg) materials. Among these studied materials the CH-Arg was found more capable for angiogenesis.