Effect of gelatin concentration, ribose and glycerol additions on the electrospinning process and physicochemical properties of gelatin nanofibers

Rheological properties of gelatin-based solutions containing different concentrations of ribose and/or glycerol were assessed before electrospun mats were manufactured and their properties investigated. Characterization included morphology, X-ray diffraction, Fourier transform infrared, solubility, swelling, the release of Maillard reaction (MR) products and their antioxidant activity. Gelatin concentrations >= 16 % w/v favoured the formation of smooth nanofibres in the electrospinning process due to their higher viscosity than for gelatin concentrations <= 14 % w/v. The diameters of the nanofibres were between 300 and 400 nm, irrespective of the concentration of gelatin and the additives. Heat treatments (80-110 degrees C) of the samples induced MR between gelatin and ribose, which provided the mats with water stability. Nevertheless, the fibrous morphology only remained for those mats heat-treated at 110 and 100 degrees C and containing 10 and 20 wt% ribose, respectively, after sample immersion in water. Heat treatment at 110 degrees C, along with glycerol addition, resulted in a decrease of solubility (from 100 to similar to 9 %) and provided a water absorption capacity (1,500-2,500 %), due to the crosslinking of ribose and glycerol with gelatin. Release of MR antioxidant compounds from the mats into water exhibited DPPH radical scavenging activity values up to 38 % (0.61 GAE mu g/mL).

Automated summary

The rheological properties of gelatin-based solutions containing different concentrations of ribose and/or glycerol were studied, as well as their effects on the properties of the electrospun mats. Heat treatment and glycerol addition resulted in improved water stability, decreased solubility, and increased water absorption capacity of the mats. The mats also released antioxidant compounds with DPPH radical scavenging activity.