Abstract
Collagen sponges are widely used in tissue engineering. Their pore size and pore-interconnection are difficult to control. The purpose of this study was to prepare highly pore-interconnected porous collagen sponges by new pore-forming method. The type I collagen liquid (0.5wt% in HCl solution, pH 3.1) was mixed with chloroform, bubbled by blade-cutter homogenization, gelled by ambient ammonia, freeze-dried and cross-linked by dehydration in vacuum oven at 140°C for six hours. The resultant collagen sponges had the surface brick layer, but sub-surface bulk area about 2mm thick consisting of many well-interconnected homogeneous pores more than 100 mm in size. It was speculated that two porogens such as chloroform and ammonia provided the collagen sponges with well inter-connected pores during freeze-drying. Osteoblast UMR106 cells successfully adhered and multiplied on cut surfaces of prepared collagen sponges. The newly prepared highly pore-interconnected porous collagen sponges might appear to be useful for future oral tissue engineering therapy.
