Preparation of collagen porous scaffolds with a gradient pore size structure using ice particulates

Direct comparison using scaffolds with a gradient pore size structure is important to investigate the effect of pore size on tissue regeneration. Collagen porous scaffolds with a pore size gradient were prepared by using pre-prepared ice particulates as a porogen material. The ice particulates had diameters of 150-250, 250-355, 355-425 and 425-500 μm. The gradient collagen scaffolds had well-interconnected pore structures with compactly packed spherical pores. The gradient pore scaffolds were used for culture of bovine articular chondrocytes, directly examining the effect of pore size on cartilage regeneration. Chondrocytes adhered and showed a homogenous distribution throughout the scaffolds. In vivo implantation results indicated that the micropores in the scaffolds prepared with ice particulates in the range of 150-250 μm showed the best effect on cartilage regeneration.