One-step electrospinning of cross-linked chitosan fibers.

Chitin is a nitrogen-rich polysaccharide that is abundant in crustaceans, mollusks, insects, and fungi and is the second most abundant organic material found in nature next to cellulose. Chitosan, the N-deacetylated derivative of chitin, is environmentally friendly, nontoxic, biodegradable, and antibacterial. Fibrous mats are typically used in industries for filter media, catalysis, and sensors. Decreasing fiber diameters within these mats causes many beneficial effects such as increased specific surface area to volume ratios. When the intrinsically beneficial effects of chitosan are combined with the enhanced properties of nanofibrous mats, applications arise in a wide range of fields, including medical, packaging, agricultural, and automotive. This is particularly important as innovative technologies that focus around bio-based materials are currently of high urgency, as they can decrease dependencies on fossil fuels. We have demonstrated that Schiff base cross-linked chitosan fibrous mats can be produced utilizing a one-step electrospinning process that is 25 times faster and, therefore, more economical than a previously reported two-step vapor-cross-linking method. These fibrous mats are insoluble in acidic, basic, and aqueous solutions for 72 h. Additionally, this improved production method results in a decreased average fiber diameter, which measures 128 +/- 40 nm. Chemical and structural analyses were conducted utilizing Fourier transform infrared spectroscopy, solubility studies, and scanning electron microscopy.