A novel globular protein electrospun fiber mat with the addition of polysilsesquioxane

The aim of this work has been to elaborate well defined gliadin nanofibers with incorporation of inorganic molecules, such as polyhedral oligomeric silsesquioxane (POSS). Nanofibers were obtained by electrospinning processing, controlling the relevant parameters such as tip-to-collector distance, voltage and feed rate. The fiber mats were characterized by SEM, confocal images, DSC, viscosity, FTIR and conductivimetry analysis. FTIR spectra showed characteristic absorption bands related to the presence of POSS-NH2 within the matrices. SEM micrographs showed that gliadin fibers decreased their dimensions as the amount of POSS-NH2 increased in the spinning solution. The electrical conductivity of gliadin solutions diminished as the concentration of POSS-NH2 was increased. Besides, confocal micrographs revealed that POSS-NH2 might be dispersed as nanocrystals into gliadin and gluten fibers. The dimension of gluten nanofibers was also affected by the POSS-NH2 concentration, but conversely, this dependence was not proportional to the POSS-NH2 amount. Somehow, the interaction between gliadin and POSS-NH2 in aqueous TFE affected the solution viscosity and, as a consequence, higher jet instabilities and thinner fiber dimensions were obtained.