Preparation of collagen porous scaffolds with controlled and sustained release of bioactive insulin

Abstract

Controlled and local release of bioactive growth factors from porous scaffolds can provide an efficient strategy to control the complex and dynamic regulation of cellular processes in a three-dimensional microenvironment. In this study, hybrid scaffolds of collagen and poly(lactic- co-glycolic acid) microbeads were prepared by introducing insulin-releasing poly(lactic- co-glycolic acid) microbeads into collagen porous scaffolds. Insulin-incorporated poly(lactic- co-glycolic acid) microbeads of two distinct sizes, 19.4 ± 1.6 and 4.4 ± 0.9 µm, were used to prepare the hybrid scaffolds. The scaffolds had controlled pore structure, and the poly(lactic- co-glycolic acid) microbeads were well distributed on the pore walls of the scaffolds. The scaffolds had a lower initial burst and a more stable insulin release than did the free microbeads. Culture of human dermal fibroblasts in the hybrid scaffolds were affected the bioactivity of released insulin. The hybrid scaffold prepared with 19.4 ± 1.6 µm microbeads had a more linear release of insulin and a higher promotion effect on cell proliferation than did the other hybrid group and control scaffolds. The hybrid scaffold should be useful for skin tissue engineering.