Liposomes decorated with β-glycine and glycine: Construction, structure and in vitro digestive stability

Liposomes were modified with different proportions of β-glycine (7S) and glycine (11S) to form Lip-7S and Lip11S. The morphology, interaction and in vitro simulated digestion of liposomes were studied. The particle size of Lip-7S is smaller than that of Lip11S. When the values of Lip-7S and Lip-11S are 1:1 and 1:0.75, respectively, the ζ - potential has the maximum absolute value and the dispersion of the system is good. The results of multispectral analysis showed that hydrogen-bond and hydrophobic interaction dominated protein-modified liposomes, the protein structure adsorbed on the surface of liposomes changed, the content of α-helix decreased, and the structure of protein-modified liposomes became denser. The surface hydrophobicity and micropolarity of liposomes decreased with the increase of protein ratio, and tended to be stable after Lip-7S (1:1) and Lip-11S (1:0.75). Differential scanning calorimetry showed that Lip-7S had higher phase transition temperature (≥170.5 °C) and better rigid structure. During simulated digestion, Lip-7S (22.5 %) released less Morin than Lip (40.6 %) and Lip-11S (26.2 %), and effectively delayed the release of FFAs. The environmental stability of liposomes was effectively improved by protein modification, and 7S had better modification effect than 11S. This provides a theoretical basis for 7S and 11S modified liposomes, and also provides a data reference for searching for new materials for stabilization of liposomes.