Preparation and properties of ProNectin F-coated biodegradable hollow fibers

ProNectin F-coated biodegradable hollow fibers were newly prepared and their cytocompatibility was evaluated in vitro. Although the coating efficiency onto poly(L-lactic acid) (PLLA) and poly(lactide-co-caprolactone) [p(LA/CL)] matrices was similar, the cell adhesion properties were greatly affected by the nature of the polymer substrate. ProNectin F-coated PLLA showed about seven times higher cytocompatibility than ProNectin F-coated p(LA/CL). The single-extruded melt spinning method and the core-sheath bicomponent melt spinning method were employed to prepare PLLA hollow fibers. The effect of the spinning conditions, such as the melt draw ratio, spinneret temperature, and take-up speed, on the diameter and wall thickness of the spun fibers was studied in detail. For single-extruded melt spinning, a segmented type of spinneret was used, and the effect of the flow rate of nitrogen, which was confined in the hollow part of fibers, was studied. X-ray photographs of the drawn hollow fibers, clarified the significant molecular orientation, which was much higher than that in drawn solid PLLA fiber under identical drawing conditions. The morphology and mechanical properties of hollow fibers demonstrated an increase in the tensile strength and a decrease in the thickness of the PLLA wall with increased nitrogen flow rates and melt draw ratios for single-extruded melt spinning. These results indicate the unique characteristics of ProNectin F-coated PLLA hollow fibers, which can be successfully utilized as a biodegradable substrate.