Supercritical CO2 assisted micronization of curcumin-loaded oil-in-water emulsion promising in colon targeted delivery

Bioavailability of oral administration is quite limited due to hydrophobicity of most of cancer drugs. Emphasis has been placed on the development of oral drug delivery systems to enhance solubility and stability of chemotherapeutics. In this work, a novel oral drug delivery system based on emulsion was implemented to encapsulate curcumin , in which ethylcellulose was employed as oil phase polymer while gum arabic was selected as emulsifier and wall material. After processed by ultrasonic emulsification , oil-in-water emulsion loaded with curcumin was transformed from liquid state to solid particles by an improved supercritical CO 2 assisted atomization technique (SAA-HCM) to achieve its long-term stability. Effects of SAA-HCM operating conditions on sizes and distributions of microparticles were investigated in detail and particle formation mechanism was discussed. The chemical stability and amorphous form of microparticles were identified by solid characterization. In vitro drug release behavior of curcumin-loaded microparticles exhibited controlled release and enzyme triggered properties, which implies the potential in the application of colon targeted delivery. This work expands the application of SAA-HCM technique to emulsion, which will be of great importance in the design of water-insoluble drug loaded microparticles with elaborate structures.