Fabrication of electrospun polyvinyl alcohol polycaprolactone-natural antibacterial agent blended nanofibrous membrane for skin tissue scaffold

Abstract

Bacterial infection can restrict and delay the wound healing process. In this study, three different kinds of natural antibacterial agents (NAA), i.e., chitosan (Cs), epsilon poly-L-lysine (EPL) and curcumin (Cur), were used with a membrane containing polyvinyl alcohol (PVA) and polycaprolactone (PCL), for inhibiting the bacterial growth meanwhile enhancing cell growth. Electrospinning was chosen to fabricate the membrane as this technique produces a nanofibrous membrane that mimics the extracellular matrix (ECM) of human tissue. Moreover, in order to increase the biocompatibility of the membrane, solution formulations containing glacial and 80% (v/v) of acetic acid were introduced to prepare PCL and PVA solutions, respectively, before mixing and adding the NAA. In this study, all electrospun nanofibrous membranes exhibited the chemical functional group of hydrophilic PVA and hydrophobic PCL. The presence of those chemical functional groups in the membranes is essential for achieving ideal scaffold properties. The presence of NAA in the membranes was further confirmed by investigating the presence of nitrogen through carbon, hydrogen, nitrogen and sulphur elemental analysis (CHNS). Overall, all electrospun nanofibrous membranes have tiny fibre diameter (92-176 nm), high porosity (77-89%), surface with hydrophilic property (0-27°), moderate body fluid uptake (209-329%) and controllable degradation rate. Although the water vapour transmission rate in the range of 1435 to 1620 g/m2/day was relatively lower than the recommended value, this did not restrict them to act as a barrier to prevent excessive water loss during wound healing. The antibacterial studies indicated that the electropun membrane containing NAA inhibited the growth of S. aureus and E. coli. Among them, electropun PVA*-PCL-EPL showed almost 99.9% of bacterial reduction after 1 h of treatment. Finally, the in vitro and in vivo studies were also conducted to confirm the effectiveness of the electrospun nanofibrous membrane in wound healing. In conclusion, all electrospun nanofibrous membranes containing PVA, PCL and NAA could be applied as a scaffold for skin tissue regeneration.