Fabrication of piezoelectric poly(l-lactic acid) nanofiber membranes with controllable properties

Poly(l-lactic acid) (PLLA) material has superior biocompatibility, degradability, and piezoelectricity, which have been chosen to fabricate electrospinning membranes to provide high surface area, porosity, and flexibility as applied in implantable medical devices. In this study, PLLA nanofiber membranes with adjustable performance were successfully prepared. The piezoelectricity, mechanical properties, and wettability could be tuned by the molecular weight of PLLA and the concentration of PLLA-Dichloromethane (DCM) solution. The maximum output voltage of the PLLA nanofiber membranes could be adjusted from 0.28 to 0.55 V, and the breaking strength could vary in the range of 6.3-10.1 MPa. Furthermore, the elongation at break can be adjusted between 22% and 142%. In addition, the wettability of PLLA nanofiber membranes could be changed from hydrophobic state to hydrophilic state by surface treatment techniques. The excellent biocompatibility was further demonstrated by cell culture on hydrophilic membranes. These results implied that the molecular weight of PLLA and the concentration of PLLA-DCM solutions could be an effective method to regulate characteristics of electrospinning membranes, which can provide more application possibilities for implantable medical devices.