Curcumin encapsulated colloidal amphiphilic block co-polymeric nanocapsules: Colloidal nanocapsules enhance photodynamic and anticancer activities of curcumin
Curcumin based novel colloidal nanocapsules were prepared from amphiphilic poly(ethylene oxide)-block-poly (propylene oxide)-block-poly(ethylene oxide) (F108). These colloidal nanocapsules appeared as spherical particles of size ranging between 270 and 310 nm. Curcumin fluorescence spectra exhibited an aggregation-induced 23 nm red-shift of the emission maximum in addition to enhancement of fluorescence quantum yield in the nanocapsules. Cytotoxicity of curcumin and colloidal nanocapsules was assessed using human derived immortalized cell lines (A549 and A375) cells in the presence and absence of irradiated light. The nanocapsules exhibited a >30-fold decrease in IC50, suggesting enhanced anticancer activity associated with curcumin encapsulation. Higher toxicity was also reported in the presence of irradiated light (as shown by the IC50, data) indicating its potential future application in photodynamic therapy. Finally, A375 cells treated with curcumin and the nanocapsules displayed significant increase in single and/or double-strand DNA breaks upon exposure to light, indicating promising biological effects.