Collagel® and Thermacol®: Collagen Hydrogel Formulations for Tissue Engineering Applications

Banes AJ, Amegashie A, McGee C. Regenerative Medicine Symposium, Research Triangle Park, NC, October 15, 2013.

Introduction: Three dimensional matrices for use in cell culture applications began with the use of fibrin clots in organ culture and acid-soluble rat tail tendon collagen adsorption to glass slides. Two early commercially available products for use in the 3D cell culture market included Matrigel™, a matrix isolated from Englebreth Holm Swarm chondrosarcoma cells, and Vitrogen® (now Purecol®, Advanced Biomatrix), an atelopeptide type I bovine collagen in solution. Collagel® is a formulation of porcine Achilles tendon (ATs) collagen with long fibrils in vitro. Thermacol® is a specially formulated mixture of collagen hydrogels of telopeptide and atelopeptide collagens isolated form porcine ATs (patent pending). Advantages of the novel formulation include longer collagen fibrils and faster, thermally sensitive gelation times. Methods:Type I collagen was isolated from porcine ATs or bovine dermis after morcelization of the cleaned ATs, pulverization and acid extractions, followed by chromatographic clean-up. Results: A formulation of telopeptide-containing collagen from tendon combined with atelopeptide collagen from dermis resulted in controlled thermal gelation when hydrogels were shifted to 37°C. Collagen fibrils in the porcine Collagel® hydrogels were significantly longer than those that comprised bovine dermis collagen preparations as evidenced by reflection interference microscopy. The thermally sensitive Thermacol® preparation in 10/90 or 20/80 telo to atelo-peptide formulations yielded a hydrogel that rapidly gelled when shifted from room temperature to 37°C. Conclusions: Mixtures of atelo and telo-peptide-containing collagen hydrogels show superior gelation kinetics to bovine dermis-derived collagens for use in cell-gel constructs for tissue engineering applications.