[Crosslinking bovine pericardial bioprosthetic heart valves by phthalocyanine sensitized photooxidation reaction].

OBJECTIVE: To crosslink bovine pericardial valves by phthalocyanine sensitized photooxidation reaction. METHODS: Fresh bovine pericardial tissues were immersed in PBS solution containing 0.01% cupreous sulfonatophthalocyanine and exposed to a broad wavelength light source for 20-120 h. Using sodium dodecyl sulfate-polyarylamide gel electrophoresis (SDS-PAGE) to analyze the cross-linking extent of pericardial tissue. With the help of attenuated total reflection-fourier transform infrared (ATR-FTIR), explained the change of protein structure after photooxidation reaction. Differential scanning calorimetry (DSC) was used to measure the change of shrinkage temperature. Tissue water content experiment method was also used. RESULTS: Photooxidized tissue was resistant to extraction when it was compared with untreated tissue and had similar crosslinking extent over glutaraldehyde-treated tissue. The three dimension structure of collagen were changed but not seriously destroyed and the model of photooxidation reaction was validated. Phthalocyanine-treated tissue was much more flexible than glutaraldehyde-treated tissue. CONCLUSION: Bovine pericardial tissue can be successfully crosslinked by phthalocyanine-mediated photooxidation reaction.

[Using chemical methods to crosslink xenogeneic heart valves: the progress of bioprosthetic heart valves].

Glutaraldehyde clinically is the most commonly accepted crosslinking reagent for bioprosthetic valves preparation. Glutaraldehyde-treated tissue is stable against chemical and enzymatic degradation; however, its calcification and cytotoxicity are severe. Dye-mediated photooxidation is an alternative tissue preservation method that oxidizes the protein with visible light in the presence of a suitable photosensitizer. This article reviews chemical mechanism, research progress, clinical applications future development of these two methods.