Accelerated fabrication of antibacterial and osteoinductive electrospun fibrous scaffolds via electrochemical deposition

Abstract

Electrospun fibrous scaffolds have attracted much research interest due to their many applications in orthopedics and other relevant fields. However, poor surface bioactivity of the polymer scaffold body significantly limits the implementation of many potential applications, and an effective solution remains a great challenge for researchers. Herein, a highly efficient method, namely pulsed electrochemical deposition (ED) with co-electrospinning nano-Ag dopant, to fabricate poly(L-lactic acid) (PLLA)/nano-Ag composite fibers is presented. The resulting product demonstrated excellent antibacterial properties, as well as strong capabilities in facilitating the precipitation of calcium phosphate crystals at fiber surfaces and in promoting osteogenic differentiation. In the process of ED, the conductivity of the fibers was observed to increase due to the nano-Ag dopant. Upon applying pulse signals when charging, water electrolysis occurred in micro-reactive regions of anodic fibers, forming OH⁻, an alkaline environment that allowed the supersaturation of calcium phosphate. When discharging, the calcium phosphate in the solution diffused rapidly and reduced the concentration polarization, reforming a homogeneous electrolyte. The realization of efficient bioactive coatings at fiber surfaces was achieved in a highly efficient manner by repeating the above charging and discharging processes. Therefore, ED can be adopted to simplify and accelerate the fabrication process of an osteogenetic and antibacterial electrospun fibrous scaffold.