In vivo compatibility and degradation of crosslinked gelatin gels incorporated in knitted Dacron

Gelatin gels were applied to porous Dacron meshes with the aim of using the se gels for local drug delivery. in this article, the biocompatibility and degradation of gelatin gels with different crosslink densities applied in D acron were studied in vivo by subcutaneous implantation in rats. Dacron dis cs were treated with carbon dioxide gas plasma to improve hydrophilicity, a nd subsequently impregnated with gelatin type B. The gelatin samples were c rosslinked to different extents using various amounts of water-soluble carb odiimide (EDC) and N-hydroxysuccinimide (NHS). After 6 h, 2, 5, and 10 days , and 3, 6: and 10 weeks of postimplantation, the tissue reactions and biod egradation were studied by light microscopy. The early reaction of macropha ges and polymorphonuclear cells to crosslinked gelatin was similar to or mi lder than Dacron. Giant cell formation was predominantly aimed at Dacron fi bers and was markedly reduced in the presence of a crosslinked gelatin coat ing. At week 10 of implantation, the crosslinked gelatin gels were still pr esent in the Dacron matrix. The gelatin degradation was less for samples wi th the highest crosslink density. The gelatin gel with the lowest crosslink density showed clear cellular ingrowth, starting after 6 weeks of implanta tion. The intermediate and high crosslinked gelatin gels showed little or n o ingrowth. In these gels, giant cells were involved in the phagocytosis of gelatin parts at week 10. Application of carbodiimide crosslinked gelatin gels in Dacron is suitable for medical applications because of the good bio compatibility of the gels and the possibility of adapting the degradation r ate of gelatin to a specific application. (C) 2000 John Wiley & Sons, inc. J Biomed Mater Res, 51, 136-115, 2000.