Impact of alginate block type on the structure and physicochemical properties of curcumin-loaded complex biopolymer nanoparticles
Zhenpeng Li, Yuying Fu, David Julian McClements, Teng Li
Abstract
In this study, core-shell complex biopolymer nanoparticles loaded with curcumin were fabricated using a simple pH-driven method. An aqueous solution containing curcumin, zein, sodium caseinate, and sodium alginate was prepared under a strongly alkaline condition (pH 12) and then acidified (pH 4). This led to the formation of curcumin-loaded complex biopolymer nanoparticles with a hydrophobic core (zein) surrounded by a hydrophilic shell (caseinate-alginate). The nanoparticles formed from β-d-mannuronic acid residues blocks (MM-blocks) had the smallest hydrodynamic diameter (202 nm), highest encapsulation efficiency (98 g/100 g), and best water-dispersibility. Transmission electron microscopy showed that the complex biopolymer nanoparticles had a core-shell structure. Fluorescence and FTIR spectroscopy were used to provide insights into the nature of the molecular hydrogen bonding and electrostatic interactions within the complex biopolymer nanoparticles. Overall, the curcumin-loaded complex biopolymer nanoparticles fabricated from MM-blocks had the best long-term storage and salt stability. These results may be useful for creating colloidal delivery systems that enhance the dispersibility, stability, and bioactivity of hydrophobic nutraceuticals.