Morphology and thermal stability of cross‐linked silk fibroin microparticles prepared by the water‐in‐oil emulsion solvent diffusion method

ABSTRACT In this work, the water‐in‐oil emulsion solvent diffusion method was developed as an alternative method for preparing cross‐linked silk fibroin (SF) microparticles. Aqueous SF solution and ethyl acetate were used as water and oil phases, respectively. Influence of cross‐linking on morphology and thermal stability of the SF microparticles were investigated. Genipin was used as a cross‐linker. The SF microparticles had spherical shape with smooth surface when Span80 was used as the oil‐soluble emulsifier. The SF in aqueous solution was cross‐linked with genipin before microparticle formation. Internal morphology of the SF microparticles observed on broken microparticles showed as sponge. The cross‐linking induced SF conformational changes from random coil to β ‐sheet form. Porosity of the SF microparticle matrices decreased and thermal stability increased when the SF was cross‐linked and the degree of cross‐linking was increased. © 2011 Curtin University of Technology and John Wiley & Sons, Ltd.