Effect of molecular weight of hyaluronan on zein-based nanoparticles: Fabrication, structural characterization and delivery of curcumin

Zein and hyaluronan with different molecular weights (hyaluronic acid, HA and sodium hyaluronate, SHA: 100, 1000, and 2000 kDa) were used to fabricate the zein-hyaluronan (ZH) nanoparticles by the antisolvent coprecipitation method. With increasing molecular weight of hyaluronan, the particle size, zeta-potential, and turbidity were gradually increased. Zeta-potential and Fourier transform infrared spectroscopy (FTIR) results indicated that electrostatic attraction was the dominant driving force, followed by hydrogen bonding and hydrophobic effects. Circular dichroism and fluorescence spectroscopy results revealed that the secondary structure was changed in zein after its combination with hyaluronan. The uniform spherical zein-HA (100 kDa) nanoparticles (size, 186.4 nm) was designed as a new delivery vehicle for curcumin with the high encapsulation efficiency (95.03%) and loading capacity (3.66%), and curcumin exhibited a better stability of anti- light degradation, and control release in simulate gastrointestinal digestion. This work would have a contribution to the development of novel delivery systems.