Inorganic-polymerization crosslinked tissue-siloxane hybrid as potential biomaterial for bioprosthetic heart valves

Bioprosthetic heart valve (BHV) replacement is increasingly used for treating valve-related diseases worldwide but the current commercially used BHVs treated with glutaraldehyde (Glut) often failed within 12-15 years due to degradation, thrombosis, inferior biocompatibility, and calcification. Herein, 3-glycidyloxypropyl trimethoxysilane (GPTMS) was used to crosslink porcine pericardium (PP) at the concentration (vol/vol) of 0.25%, 1%, 2%, and 4% and their performance for potential application in BHVs was evaluated. The crosslinking mechanism mainly involved the ring-opening of epoxide by amine attack and silanol poly-condensation. The stability of collagen in higher concentration (1%, 2%, and 4%) GPTMS crosslinked PPs (GPTMS-PPs) was clearly increased. GPTMS-PPs showed no cytotoxicity and supported the growth of endothelial cells while Glut-PP did not. GPTMS-PPs were less prothrombotic than Glut-PP. GPTMS-PP crosslinked at 1% concentration showed comparable mechanical properties to Glut-PP while had better anti-tearing performance. The subcutaneous implantation in rat for 30 days showed that GPTMS crosslinking was able to effectively inhibit the calcification of BHV.