Tissue response and biodegradation of composite scaffolds prepared from Thai silk fibroin, gelatin and hydroxyapatite
This work aimed to investigate tissue responses and biodegradation, both in vitro and in vivo, of four types of Bombyx mori Thai silk fibroin based-scaffolds. Thai silk fibroin (SF), conjugated gelatin/Thai silk fibroin (CGSF), hydroxyapatite/Thai silk fibroin (SF4), and hydroxyapatite/conjugated gelatin/Thai silk fibroin (CGSF4) scaffolds were fabricated using salt-porogen leaching, dehydrothermal/chemical crosslinking and an alternate soaking technique for mineralization. In vitro biodegradation in collagenase showed that CGSF scaffolds had the slowest biodegradability, due to the double crosslinking by dehydrothermal and chemical treatments. The hydroxyapatite deposited from alternate soaking separated from the surface of the protein scaffolds when immersed in collagenase. From in vivo biodegradation studies, all scaffolds could still be observed after 12 weeks of implantation in subcutaneous tissue of Wistar rats and also following ISO10993-6: Biological evaluation of medical devices. At 2 and 4 weeks of implantation the four types of Thai silk fibroin based-scaffolds were classified as “non-irritant” to “slight-irritant”, compared to Gelfoam® (control samples). These natural Thai silk fibroin-based scaffolds may provide suitable biomaterials for clinical applications.
KeywordsHydroxyapatite Silk Fibroin Bone Tissue Engineering Gelfoam Silk Fibroin Scaffold
The financial supports from the 90th Anniversary of Chulalongkorn University Fund (Ratchadaphiseksomphot Endowment Fund), Chulalongkorn University Centenary Academic Development Project and National Research Council of Thailand are highly acknowledged. H.T. also thanks Polymer Engineering Laboratory, Biomedical Engineering Laboratory (Faculty of Engineering), and i-Tissue Laboratory (Faculty of Medicine), Chulalongkorn University for the support of laboratory facilities.
- 8.ISO10993-6. Biological evaluation of medical devices—part 6: tests for local effects after implantation.Google Scholar
- 10.Tagchi T, Kishida A, Akashi M. Hydroxyapatite formation on/in poly(vinyl alcohol) hydrogel matrices using a novel alternate soaking process. Chem Lett. 1998;711–712.Google Scholar
- 14.Dykstra JM. A manual of applied techniques for biological electron microscopy. Drying samples with hexamethyldisilazane. New York: Plenum; 1993. p. 109.Google Scholar
- 18.Chunling D, Jun J, Yucheng L, Xiangdong K, Kemin W, Juming Y. Novel silk fibroin/hydroxyapatite composite films: structure and properties. Mater Sci Eng. 2009;C29:62–8.Google Scholar