Enhanced tissue penetration-induced high bonding strength of a novel tissue adhesive composed of cholesteryl group-modified gelatin and disuccinimidyl tartarate.

The aim of this study was to evaluate the effect of cholesteryl group content on the bonding strength of a novel tissue adhesive composed of cholesteryl group-modified geletin (CholGltn) and disuccinimidyl tartarate (DST). The bonding strength of this tissue adhesive with fresh arterial media reached a maximum at a CholGltn content of 70% in the CholGltn/gelatin (Gltn) mixture, which then decreased with increasing CholGltn content with a fixed succinimidyl group:amino group ratio of 1:1. The maximum bonding strength obtained was 6-fold higher compared with that of the original Gltn. Furthermore, maximum peeling strength was also obtained at a CholGltn content of 70% in the CholGltn/Gltn mixture and at a similar succinimidyl group:amino group ratio. The highest peeling strength was 8-fold higher compared with Gltn and 6-fold higher compared with commercial aldehyde-based adhesive. After exposure of FITC-labeled Gltn or CholGltn to aortic smooth muscle cells (SMCs), which are abundant in arterial media, CholGltn integrated effectively with the surface of SMCs. This indicated that FITC-labeled CholGltn anchors into the cell membrane of SMCs. From these results, it was demonstrated that tissue adhesive composed of a CholGltn/Gltn mixture and DST showed improved penetration into arterial media compared with adhesive composed of Gltn and DST. This behavior supports the suggestion that the hydrophobic cholesteryl group in Gltn contributes to the enhanced bonding/peeling strength. This novel tissue adhesive may become a useful material in the clinical field for the treatment of aortic dissection.