This study aimed to develop hybrid electrospun chitosan–phospholipid nanofibers and investigate the effect of phospholipid (P) content and chitosans (Ch) molecular weights (Mw) and degree of acetylation (DA), on the morphological, mechanical and mucoadhesive properties of the nanofibers. Electrospun Ch/P nanofibers exhibited a smooth and uniform surface with average diameters ranging from 300 to 1000 nm, as observed by scanning electron microscopy (SEM). The average diameter of the nanofibers was observed to increase with the increase of the Mw and degree of deacetylation of Ch, and phospholipid content. The elastic and adhesive properties of the nanofibers were determined by atomic force microscopy, and displayed higher values for higher Mw and lower DA Ch used. The elastic modulus of electrospun Ch/P hybrid fibers determined for the different conditions tested was found to be in the range of 500 and 1400 MPa. Furthermore, electrospun Ch/P nanofibers displayed mucoadhesive properties expressed by the work of adhesion calculated after the compression of the nanofibers against a section of pig small intestine. Our results showed that the increase in phospholipid content and DA of Ch decrease the work of adhesion, while the increase of Mw resulted in slightly higher work of adhesion of the nanofibers.

Electrosprayed ethyl cellulose core–shell microcapsules were produced for the encapsulation of probiotic Bifidobacterium animalis subsp. lactis (Bifido). Ethyl cellulose (ETC) was used as a shell material with different core compounds (concentrated Bifido, Bifido–maltodextrin and Bifido–glycerol). The core–shell microcapsules have an average diameter between 3 µm and 15 µm depending on the core compounds, with a distinct interface that separates the core and the shell structure. The ETC microcapsules displayed relatively low water activity (aw below 0.20) and relatively high values of viable cells (109–1011 CFU/g), as counted post-encapsulation. The effect of different core compounds on the stability of probiotics cells over time was also investigated. After four weeks at 30 °C and 40% RH the electrospray encapsulated samples containing Bifido–glycerol in the core showed a loss in viable cells of no more than 3 log loss CFU/g, while the non-encapsulated Bifido lost about 7.57 log CFU/g. Overall, these results suggest that the viability of the Bifido probiotics encapsulated within the core–shell ETC electrosprayed capsules can be extended, despite the fact that the shell matrix was prepared using solvents that typically substantially reduce their viability.