Effect of protein-loading on properties of wet-spun poly(L,D-lactide) multifilament fibers

Protein-loaded multifilament fibers were fabricated by the wet-spinning method. The polymers which were tested included poly(L,D-lactide) [P(L,D)LA], L/ D ratio 96/4 and poly(L,DL-lactide) [P(L,DL)LA], L/DL ratio 70/30. The polymers were dissolved in dichloromethane and bovine serum albumin (BSA) was dissolved in water, respectively. The solutions were mixed together using a probe sonicator to form a polymer-protein emulsion. This emulsion was extruded to an ethanol spin bath. The fibers possessed a distinct sheath-core structure, where the inner core was porous and the outer sheath was smooth. The diameters of the filaments were in the range of 46 and 70 lm. The tenacity values of the filaments were between 7 and 17 MPa. In vitro drug release rate of the P(L,DL)LA 70/30 filament was faster than that of the P(L,D)LA 96/4 filament.