Physical–chemical stability and in vitro digestibility of hybrid nanoparticles based on the layer-by-layer assembly of lactoferrin and BSA on liposomes
Hybrid nanoparticles were fabricated by the electrostatic deposition of positive bovine serum albumin (BSA) and negative lactoferrin (LF) onto the surface of anionic nanoliposomes (NLs). The resulting particles had a cumulative size of 156.27 ± 11.0 nm and decreased in negative charge. Transmission electron microscopy (TEM) revealed that the hybrid particles formed a smooth and spherical polyelectrolyte complex after globular protein deposition. Observations in size distribution and surface charge after heat treatment, pH alteration and long-term storage found that the particles coated with layers of polyelectrolytes, BSA and LF, had obviously better stability than the bare liposomes. In an in vitro gastrointestinal digestion study, monolayer coated NLs (LF-NLs) and double-layer coated NLs (BSA-LF-NLs) had similar changes in microstructure (TEM) and the release rate of model cargos (calcein), which were superior to the uncoated NLs. These results indicated that hybrid nanoparticles coated with the polyelectrolytes of BSA and LF on the surface of liposomes by electrostatic interaction may improve liposomal stability, and showed some implications for the fabrication of functional molecular delivery systems to control physical–chemical and digestion stability in food and nutrition areas.