Amorphous nano-curcumin stabilized oil in water emulsion: Physico chemical characterization

- Curcumin is nanonized to reduce size and change polymorphism.
- Nanonized curcumin is amorphous in nature.
- Protein avoided recrystallization of nanonized curcumin.
- Nanonized curcumin reduced interfacial tension between oil and water.
- Nanonized curcumin stabilized emulsions are stable for 30 days at 4 °C.

Particle characteristics e.g. size and polymorphism are known to significantly affect the Pickering ability of the solid particles by influencing their interaction at the oil and water (O/W) interface. In this study, nano-sized amorphous curcumin particles were fabricated using nanonization technology to use them as Pickering particles.After nanonization, native crystalline curcumin particles were converted into amorphous, nanosized particles of ∼220 nm. Amorphous nature of the particle was evident from the decreased melting point from 177 ± 1 °C (native curcumin) to 146 ± 3 °C (nanonized curcumin) and enthalpy from 27 ± 2 J/g to 3.5 ± 1 J/g.Interfacial tension (IFT) studies have shown a decrease in IFT at the O/W interface from ∼27 mN/m to ∼15 mN/m in the presence of amorphous curcumin particles in water phase compared to crystalline curcumin particles. Curcumin stabilized O/W emulsion has an initial droplet size of ∼1.2 μm and they were stable for 30 days at 4 °C.