Control of the porous structure of cellulose-based tissue engineering scaffolds by means of lyophilization

Abstract

The porous structure of tissue engineering scaffolds that serve as templates for bone tissue regeneration must be precisely designed as it is related to cell adhesion, proliferation, differentiation and vascularization. In this work, the morphology of a three-dimensional matrix of regenerated cellulose prepared by the freeze-drying method was studied. The regenerated cellulose-based gel was obtained by saponification of cellulose acetate. Lyophilization was chosen to create a highly porous matrix with an optimal pore size required for successful bone regeneration. It was found that the porous structure of the gel depended on the solution in its discontinuous phase prior to the drying process. By changing the concentration of ethanol in the discontinuous phase, the morphology of the lyophilized matrix varied from macroporous to dense. The matrix of the desired morphology with micro and macro pores was obtained by lyophilization of the gel, which was filled with 20% of ethanol solution in water and pre-frozen at -25ºC. The cellulose based matrix showed a permeable pore network for glucose, thus substantiating its suitability for the fast diffusion of nutrients.