Selected natural fibers and their electrospinning

Unlike synthetic fibers which cause serious ecological issues, natural fibers are considered as an attractive alternative due to their eco-friendly nature. Natural fibers are viable materials which are abundant in nature and have several benefits over synthetic fibers such as low cost, light weight, biocompatibility, and biodegradability. Natural nanofibers possess various advantages over traditional microfibers. These include high surface-to-volume ratio which enhances their functionalization and enables their usage in nano mats and scaffolds. Such properties are highly demanded for different applications especially in the biomedical and filtration fields. Several techniques have been introduced for the fabrication of natural nanofibers. Electrospinning is considered one of the most attractive techniques to produce natural nanofibers due to its simplicity and high quality coupled with low cost. Over the past decade, a surge in the utilization of natural nanofibers through electrospinning has been found in the literature. Nonetheless, there is a lack of review articles covering the natural fibers and their electrospinning. Therefore, this review article covers the sources, structures, and properties of selected natural fibers, namely, silk, cellulose, and wool and their electrospinning. Further, some of the most common applications of their electrospun nanofibers are also discussed. Unfortunately, some of these natural fibers cannot be electrospun in their pristine conditions. They require special pre-electrospinning treatments. In addition, some post-electrospinning treatments may be required to improve the final properties of the electrospun nanofibers. It is believed that modification of the natural nanofibers by pre-spun and post-spun treatments could widen their applications especially in biomedical and filtration fields.