Fabrication of self-assembled Radix Pseudostellariae protein nanoparticles and the entrapment of curcumin

Simulating the process of traditional Chinese medicine decoction, Radix Pseudostellariae protein (RPP)-based nanoparticles were constructed by combining heat treatment with pH adjustment in succession. The formed nanoparticles were characterized as homogeneously dispersed sphere within 100 nm in diameter. With curcumin as a drug model, the potential application of RPP as a nanocarrier was studied. Curcumin could combine to RPP through hydrophobic interaction and quench the intrinsic fluorescence of RPP. Results of X-ray diffraction revealed that the crystal formation of curcumin was suppressed after the formation of nanocomplexes. In addition, the curcumin-loaded nanocomplexes exhibited good thermal stability and the light stability of curcumin was significantly improved. The curcumin-loaded nanocomplexes had stronger reducing power than free curcumin, which displayed additive effect between curcumin and RPP. In summary, the obtained RPP nanoparticles are potential to become new drug delivery carriers in food field and pharmaceutical applications for the encapsulation of hydrophobic components.