Improvement on stability, loading capacity and sustained release of rhamnolipids modified curcumin liposomes

A novel cholesterol-free curcumin delivery system was fabricated by rhamnolipids modified liposomes (RL-Lps). The incorporation of the rhamnolipids increased the sphericity, reduced the size, and decreased the polydispersity of the liposomes compared with pure liposomes (Lps). Analysis of the environmental stability of the RL-Lps showed they have good long-term stability over a wide range of pH (2-3 and 5-8), ionic strengths (0-200 mM), and accelerated centrifugal conditions. The curcumin-loaded rhamnolipids modified liposomes (Cur-RL-Lps) could be prepared with a relatively high loading efficiency (LE > 90%) and loading capacity (LC > 3.5%). The thermal and photochemical stability of the curcumin was improved after encapsulation in the Cur-RL-Lps. In vitro release studies indicated that the sustained release of the curcumin was prolonged when rhamnolipids were incorporated into the liposomes. This study shows that rhamnolipids have great potential for liposomal delivery system suitable for utilization in functional foods, dietary supplements, and pharmaceutical preparations.