In vitro blood compatibility evaluation of silk fibroin by chemical crosslinking

Abstract

Poly(ethylene glycol) diglycidyl ether (PEG-DE) has been used as a crosslinker to construct artificial blood vessels of silk fibroin, endowing materials suitable compliance. As a biomaterial directly contacting with blood, it requires excellent anticoagulant property. In this article, hemolysis, platelet adhesion, platelet activity and plasma recalcification time of PEG-DE crosslinked silk fibroin were investigated using absorption spectrometry, scanning electron microscopy, methyl thiazolyl tetrazolium analysis and the time counting method. The hemolysis at ratios of PEG-DE crosslinked silk fibroin materials was < 0·5%, although it increased with increasing PEG-DE content. The platelet adhesion ratio and aggregation activity of PEG-DE crosslinked silk fibroin were higher than those of ethanol treated silk fibroin and increased with increasing PEG-DE content. However, the plasma recalcification time of PEG-DE crosslinked silk fibroin was longer than that of the ethanol treated silk fibroin and increased slightly with the increase of PEG-DE content. Based on these, PEG-DE used to crosslink silk fibroin showed different anticoagulant characteristics in different coagulation pathways.