A strategy for biomimetic hybridization of electrospun fiber mat cross-sections

Concentrated synthetic body fluid (c-SBF) recipes have been used in biomimetic deposition of calcium phosphate (CaP) phases on electrospun polycaprolactone (PCL) fiber mats. However, cross-sections of mats could not be coated entirely when simple soaking methods had been used. In this study, calcium and phosphate sources that are used in typical c-SBF recipes were placed in two compartments which were separated by PCL fiber mats. By varying the concentrations of calcium and phosphate sources in either compartment according to a thermodynamic model, the difference between pH levels of compartments was adjusted. A gradual and homogeneous increase in supersaturation levels was achieved on both sides of the membrane with the onset of diffusion of species through the membrane. The strategy of separation of c-SBF constituents permitted coatings that extended through the cross-section of mats. In addition, types of CaP phases that can be precipitated on opposite sides of the membrane under different conditions were predicted by the same thermodynamic model. It was possible to coat the cross-sections of mats with the targeted phase mixtures by using the developed modeling approach.

► A strategy for coating cross-sections of electrospun fiber mats is developed.
► Constituents of concentrated CPS were separated with mats to be coated.
► Both, sides and the cross-sections of fiber mats were coated simultaneously.
► Alternative that resulted in a biphasic and a single phase coating on opposite sides was predicted by thermodynamic model used.
► Coatings were changed from single phase to biphasic by decreasing the difference in pH values of the compartments.