Effectiveness of temperature and preparation method on stability kinetic of Curcumin nanodispersion: Cytotoxicity and in vitro release assessment

Curcumin is a natural and non-polar pigment with unique properties such as antioxidant activity that has been widely utilized in food and pharmaceutical formulations. In this study, solvent displacement and subcritical water methods were used to prepare Curcumin nanodispersions. The influences of the method and storage temperature were evaluated on physical and chemical stability of the prepared nanodispersions. Obtained results indicated that prepared transparent nanodispersions maintained their physical and chemical stability at 4 and 25 degrees C for 4 months. The results also showed that the prepared nanodispersions using subcritical water (temperature of 120 degrees C and pressure of 1.5 atm for 2 h) had a higher stability (minimum changes in the particle size) and less Curcumin loss (0.36%). Release of Curcumin from prepared nanodispersions was also evaluated at different pH values (1.2, 5.4, and 7.4) and the results indicated that its release rate was higher in pH values ranging 5 to 7. Kinetic study showed that release of Curcumin from dialysis bag was controlled by diffusion at pH value of 7.4 with a high constant rate. The viability percentage of HT-29 cells against pure Curcumin and Curcumin nanodispersions prepared using solvent displacement and subcritical water methods for 72 h incubation were 94, 30 and 18%, respectively. Moreover, In drug delivery systems, mathematical modeling and simulation play an important role in elucidating important drug release mechanisms; therefore, the results of experimental data of diffusion rate were compared with those obtained from simulation, and a good agreement was found.

Automated summary

Curcumin nanodispersions were prepared using solvent displacement and subcritical water methods, and their physical and chemical stability was evaluated under different storage temperatures. The nanodispersions prepared with subcritical water showed higher stability and less Curcumin loss compared to other methods. The release rate of Curcumin from the nanodispersions was higher at neutral pH values, and diffusion was the main mechanism of release at pH 7.4. The viability of HT-29 cells was higher when exposed to pure Curcumin compared to the nanodispersions, and mathematical modeling and simulation showed good agreement with experimental data.