PHBV tissue engineering scaffolds fabricated via emulsion freezing / freeze-drying: effects of processing parameters

Abstract

Biodegradable polymers have been widely used for scaffolds in tissue engineering which aims to form completely natural tissues without leaving permanently synthetic element(s) in the human body. Poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) is a natural, biocompatible and biodegradable polymer suitable for tissue engineering applications. This paper reports the fabrication and characterization of three dimensional, highly porous PHBV scaffolds produced through the emulsion freezing/freeze-drying technique. PHBV emulsions having 2.5%, 5%, 7.5%, 10%, 12.5% (w/v) PHBV concentrations were used. Freezing and freeze-drying of polymer/solvent/water phase emulsions produced hard and tough scaffolds with interconnected pores having good handling quality. The porosity of scaffolds changed from 85% to 71% when the PHBV concentration in emulsions increased from 2.5% to 12.5%. Compressive mechanical properties of scaffolds were increased with increasing PHBV concentration. The scaffolds had pore sizes ranging from several microns to a few hundred microns.