Development of Curcumin Based Ophthalmic Formulation

Problem statement: Ophthalmic drug delivery system has been a major challenge due to the distinctive and unique anatomy of the eye. The use of phytochemicals for the application in ocular disease has not been investigated much, due to poor pharmacokinetics of phytochemical and hence poor therapeutic efficacy. Approach: Curcumin is one such phytochemical known for its medicinal properties, but its usage has been limited due to its poor bioavailability. Therapeutic ocular application of curcumin for indications such as allergic conjunctivitis and use of nanotechnology based delivery system for increasing its bioavailability haven’t been explored much. Thus the objective of current study was to develop a nanoemulsification based formulation for curcumin with enhanced bioavailability and efficacy for ophthalmic therapeutic application. Different surfactants and oils were screened based on its ability to solubilize hydrophobic curcumin for developing formulation. Ultrasonication was used for dispersion of curcumin in surfactants and nanoemulsification. Charecterization of the selected formulation was done based on particle size, Transmission Electron Microscope (TEM) and Scanning Electron Microscope (SEM) analysis and tested for different physiochemcial properties. Results: A novel formulation was developed through nanoemulsification technology by ultrasonication using carefully selected nonionic surafactants. Acconon and Tween 80 were chosen after thorough screening studies. The ratio of curcumin: Acconon: Tween80: water (0.12:1:7:1) was found to be optimum for the formulation. Particle size analysis showed that the nano droplets are in the range of 8-22 nm. Further the TEM and SEM studies also confirmed that the nanodroplets are in spherical shape. Formulation was found to be stable as ascertained by phase separation and observational studies. Conclusion: The studies ensured the stability and formation of characteristic nanodroplets with curcumin entrapment as a result of the developed formulation. The so developed formulation is expected to have higher ophthalmic bioavailability, which further needs to be confirmed through in vitro and in vivo studies.