Whey protein concentrate doped electrospun poly(epsilon-caprolactone) fibers for antibiotic release improvement

Abstract

Design and fabrication of scaffolds using appropriate biomaterials are a key step for the creation of functionally engineered tissues and their clinical applications. Poly(epsilon-caprolactone) (PCL), a biodegradable and biocompatible material with negligible cytotoxicity, is widely used to fabricate nanofiber scaffolds by electrospinning for the applications of pharmaceutical products and wound dressings. However, the use of PCL as such in tissue engineering is limited due to its poor bioregulatory activity, high hydrophobicity, lack of functional groups and neutral charge. With the attempt to found nanofiber scaffolds with antibacterial activity for skin tissue engineering, in this study, whey protein concentrate (WPC) was used to modify the PCL nanofibers by doping it in the PCL electrospun solution. By adding proteins into PCL nanofibers, the degradability of the fibers may be increased, and this further allows an antibiotic incorporated in the fibers to be efficiently released. The morphology, wettability and degradation of the as-prepared PCL/WPC nanofibers were carefully characterized. The results showed that the PCL/WPC nanofibers possessed good morphology and wettability, as well as high degradation ability to compare with the pristine PCL fibers. Afterwords, tetracycline hydrochloride as a model antibiotic drug was doped in the PCL/WPC nanofibers. In vitro drug release assays demonstrated that PCL/WPC nanofibers had higher antibiotic release capability than the PCL nanofibers. Also, antibacterial activity evaluation against various bacteria showed that the drug-doped PCL/WPC fibers possessed more efficient antibacterial activity than the PCL nanofibers.

Keywords: Antibacterial activity; Electrospinning; Nanofiber; Poly(epsilon-caprolactone); Whey protein concentrate.