Quaternized curdlan/pectin polyelectrolyte complexes as biocompatible nanovehicles for curcumin

Abstract In this study, a positively charged quaternized curdlan (Qcurd) was used to fabricate polyelectrolyte complex nanoparticles (PEC NPs) with a negatively charged pectin via electrostatic complexation. Results showed that the Qcurd/pectin PEC NPs prepared with 0.5 mg/mL Qcurd and pectin solutions, 1:2 pectin/Qcurd mass ratio, and pH 4.0 in the absence of NaCl were characterized by a spherical morphology in nanoscale, an average particle size of 68 nm, and good dispersibility in aqueous solutions. Curcumin was encapsulated in the Qcurd/pectin PEC NPs through hydrogen bonding with an encapsulation efficiency of ∼82%, a loading content of 13%, and a pH-dependent controlled release. Curcumin-loaded PEC NPs exhibited a significantly enhanced water solubility, excellent free radical scavenging ability and antioxidant capacity in vitro as compared with those of free curcumin.