Emulsion formulation of curcumin in soybean oil with a combination surfactant of Tween-80 and lecithin using wet ball milling method

Curcumin has commonly known to have many pharmacological benefits; however, low solubility and bioavailability hamper its application. Curcumin formulation in a micelle or liposomal delivery system using lecithin-Tween 80 is expected to overcome the aforementioned problems. In this study, correlation between lecithin: curcumin ratio and emulsion physical properties are examined. Curcumin emulsion consists of soybean oil, water, Tween-80, and various lecithin (0.0092-0.92 g) and curcumin mass (0.01 - 0.025 g), which are mixed with wet ball milling method for 24 hours. Particle size distribution, polydispersity index and encapsulation efficiency are evaluated using Dynamic Light Scattering technique and UV-Vis spectrophotometer respectively. Our results show that the addition of lecithin while curcumin mass is constant, increases the particle size, 367 to 1647 nm, with polydispersity index of 0.202 to 0.622. In contrast, the increment of curcumin mass while lecithin mass is constant does not drastically enlarge the particle size, 298 to 386 nm, with polydispersity index of 0.221 to 0.295. Encapsulation efficiency is decreasing in the addition of lecithin (81% to 22%) and increases as more curcumin is added (31% to 75%). Furthermore, the pattern of the results obtained is in accordance with the previous molecular simulation study. It is confirmed that the addition of lecithin changes particle size which might be due to the shape alteration from spherical to rod-like structure while the increment of curcumin does not significantly alter the particle shape and size.