Construction And Properties Of Tissue Engineering Scaffold For Myocardial Scar Therapy

To construct a tissue engineering scaffold which could be injected with seed cells and forming in vivo for myocardial scar therapy, Chitosan/Glycerophosphate(CS/GP) thermosensitive hydrogels was chose to modify its mechanical property. Hydroxy propyl methyl cellulose(HPMC), Nano silk fibroin(nSF) and polyethylene glycol(PEG) was added into CS/GP by liquid blending. The mixtures were placed in test tubes in water bath of 37℃, 15 min, then take them out and placed up side down to evaluate the gelation property of the mixtures. The tensile strength and the elongation at break of the mixtures were determined by tensile test. Result shows the CS/GP/PEG mixture has a faster gelation rate and a better mechanical property. SEM graphic revealed the porosity of the lyophilized sample of CS/GP/PEG. IR data implied the PEG and the CS is combined by hydrogen bond and twine.Base on the results of above researches, CS/GP, CS/GP/PEG and CS/GP/PEG/nSF hydrogels were chose to studied on biocompatibility. The result of in vitro degradation test shows the nSF could enhance the degradation rate while the PEG slow down it. Hemolysis test and platelet adhesion test revealed a low hematolysis rate and a low platelet adhesion rate of the hydrogels, which means a good blood compatibility of the hydrogels. Cytotoxicity test shows the hydrogels has no cell toxicity but a promotion for L929 cells, and the promotion ability is relevant to the concentration of the leach liquor. At last, The acute toxicity test shows the materials has no acute toxicity.Researches revealed a good biocompatibility of the CS/GP/PEG hydrogels, which is worth of futher study as a injectable myocardial tissue engineering scaffolds.