Design of a lipid nanovesicle system encapsulating bacteriophages integrated in a multiple emulsion formulation: a proof-of-concept

Development of a biotechnological process for the inhalational administration of a bacteriophage was pursued, using strategies of nanoencapsulation within lipid nanovesicles. As a proof-of-concept for the nanoencapsulation strategy, a bacteriophage with broad lytic spectrum was entrapped within W/O/W multiple nanoemulsions. Physicochemical characterization of the optimized bacteriophage-encasing nanovesicles encompassed determination of particle hydrodynamic size, size distribution and particle charge via DLS, surface morphology via CRYO-SEM, and thermal analysis via DSC, whereas antimicrobial activity of the nanoemulsions produced was assessed in vitro using several bacterial strains. The optimized nanosystems showed no phase separation and encompassed nanovesicles with an average size of ca. 114 nm and an average Zeta Potential of ca. -13 mV, which were maintained stable over a storage timeframe of ca. 3 months.