Development and characterization of PEGylated and carboxymethyl chitosan-coated fish oil liposomes

Abstract

Fish oil is a rich source of omega-3 long chain polyunsaturated fatty acids (PUFAs), such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). The highly lipophilic nature of fish oil results in poor absorption and palatability, in addition to deterioration by oxidation, and these factors limit their use in functional foods. Therefore, protection of fish oil during processing and storage is important. In this study, different concentrations of carboxymethyl chitosan (CMCS)-coated and PEGylated liposomes containing fish oil were prepared and characterized. The CMCS coating increased the mean diameter whereas entrapment efficiency of liposomes did not showed any significant change when coated with CMCS and PEG. Similarly, there was no effect on zeta potential with polymer coating. The fish oil liposomes were freeze-dried to ensure long-term stability. The surface structure and characteristics of liposomes were determined. The Fourier transform infrared spectroscopy (FT-IR) showed that the hydrogen bonding formed between the CMCS and the carbonyl region of the liposomes’ bilayer. Transmission electron microscopy images revealed the few spherical, most rectangular and nano-size particle distribution. This study can provide theories and practical information for further applications of fish oil into different pharmaceutical and nutraceutical products. Further in vitro release study can be carried out to understand the release behavior of polymer-coated fish oil liposomes.