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Electrospun chitosan-based nanocomposite mats reinforced with chitin nanocrystals for wound dressing

The aim of this study was to develop electrospun chitosan/polyethylene oxide-based randomly oriented fiber mats reinforced with chitin nanocrystals (ChNC) for wound dressing. Microscopy studies showed porous mats of smooth and beadless fibers with diameters between 223 and 966 nm. The addition of chitin nanocrystals as well as crosslinking had a positive impact on the mechanical properties of the mats, and the crosslinked nanocomposite mats with a tensile strength of 64.9 MPa and modulus of 10.2 GPa were considered the best candidate for wound dressing application. The high surface area of the mats (35 m(2)g(-1)) was also considered beneficial for wound healing. The water vapor transmission rate of the prepared mats was between 1290 and 1,548 gm(-2)day(-1), and was in the range for injured skin or wounds. The electrospun fiber mats showed compatibility toward adipose derived stem cells, further confirming their potential use as wound dressing materials.

Electrospinnability of bionanocomposites with high nanocrystal loadings: The effect of nanocrystal surface characteristics

This paper deals with the effect of solution properties and nanoparticle surface chemistry on the spinnability of a chitosan/polyethylene oxide (PEO) with high concentration (50wt%) of chitin and cellulose nanocrystals and the properties of the resultant nanocomposite fibers/fiber mats. Electrospinning dispersions with cellulose nanocrystals having sulphate surface groups showed poor spinnability compared to chitin nanocrystals with amide and amino groups. Chitin nanocrystal based dispersions showed good spinnability and continuous fiber formation whereas cellulose nanocrystal system showed discontinuous fibers and branching. The viscosity and surface tension are shown to impact this behavior, but conductivity did not. Poor spinnability observed for cellulose nanocrystal based fibers was attributed to the coagulation of negatively charged cellulose nanocrystals and positively charged chitosan. The study showed that the nanocrystal surface charge and interactions with the chitosan/PEO matrix have a significant impact on the spinnability of bionanocomposites.