From fabric to tissue: Recovered wool keratin/polyvinylpyrrolidone biocomposite fibers as artificial scaffold platform

Keratin extracted from wool fibers has recently gained attention as an abundant source of renewable, biocompatiblematerial for tissue engineering and drug delivery applications. However, keratin extraction andprocessing generally require a copious use of chemicals, not only bearing consequences for the environment butalso possibly compromising the envisioned biological outcome. In this study, we present, for the first time,keratin-PVP biocomposite fibers obtained via an all-water co-electrospinning process and explored their propertiesmodulation as a result of different thermal crosslinking treatments. The protein-based fibers featuredhomogenous morphologies and average diameters in the range of 170-290 nm. The thermomechanical stabilityand response to a wet environment can be tuned by acting on the curing time; this can be achieved withoutaffecting the 3D fibrous network nor the intrinsic hydrophilic behavior of the material. More interestingly, ourprotein-based membranes treated at 170 °C for 18 h successfully sustained the attachment and growth of primaryhuman dermal fibroblasts, a cellular model which can recapitulate more faithfully the physiological humantissue conditions. Our proposed approach can be viewed as pivotal in designing tunable protein-based scaffoldsfor the next generation of skin tissue growth devices.