A study on chitosan-coated liposomes as a carrier of bovine serum albumin as oral protein drug

The development of protein drug liposomes was limited due to the instability of the structure of liposomes, such as easy aggregation, easy fusion, and drug leakage. The object of this work was to prepare bovine serum albumin (BSA) loaded liposomes (BSA-Lip) using BSA as a protein model drug and then BSA-Lip was further coated with chitosan (CH-BSA-Lip) in order to improve the stability of phospholipid bilayer membrane. It was found that the particle size of BSA-Lip increased after being coated with chitosan and the surface potential changed from negative charge to positive charge due to the electrostatic interaction between liposomes and chitosan. After chitosan coating, the encapsulation efficiency of liposomes also increased due to the interaction between positively charged chitosan and negatively charged BSA. Fourier transform infrared spectroscopy analysis confirmed that BSA was encapsulated into liposomes and chitosan was successfully coated on the surface of liposomes. Transmission electron microscopy showed that the particles were nanosized and spherical. The physical stability and in vitro digestion stability of liposomes were examined by observing the changes of particle size and potential. It was found that chitosan coating enhanced the stability of liposomes significantly. The in vitro release profile of CH-BSA-Lip possessed a slow release behavior, and BSA release was governed by both diffusion and dissolution from phospholipid bilayer.