Electrospinning of hyaluronic acid (HA) and HA/ gelatin blends

In the present study, electrospinning of hyaluronic acid (HA) and hyaluronic acid/gelatin (HA-GE) blends in N,N-dimethylformamide (DMF)/water-mixed solvents have been investigated. When the volume ratio of DMF to water was in the range of 1.5-0.5, HA solutions could be electrospun into fibrous membranes successfully. The average diameter of HA fibers was about 200 nm. The HA-GE composite nanofibrous membranes with varied HA/GE weight ratio in the range of 100/20-100/100 have also been successfully fabricated. The average diameter of HA-GE fibers was in the range of 190-500 nm. The decrease in surface tension could promote fiber formation. Thus, an introduction of DMF that could decrease the surface tension distinctively, without significant change or increase in viscosity of the solution, could bypass the use of blowing-assisted electrospinning. Our postulated picture is that the lower surface tension could help the ejection of stream with relatively high viscosity and reduce or prevent the droplet formation during the spinning process.