Control of the release of curcumin from micelles by ultrasound

In this study, ultrasound was employed to control the release of curcumin entrapped in micelles. Stable micelles were formed in water from a mixture of surfactants (Tween 80 and lecithin in a 1:0.3 mole ratio) with ethyl oleate. The weight ratio of water:surfactants:oleate was 10:2.62:1. One mg of curcumin was solubilized in 4.67 mL of micelle solution. Under 40 kHz insonation from a probe sonicator, much of the curcumin was released from the micelles and formed insoluble aggregates, as evidenced by decreased UV-vis absorption at 420 nm. The initial release rate (assayed by the rate of absorption change) decreased at acidic pH, but was about 3.5 μg/s (1.87 %/sec) in a PBS buffer at neutral or alkaline pH.