Nanocomplex of selachyl alcohol and sodium caseinate: Preparation, physicochemical properties, and interaction mechanism

Selachyl alcohol (SA), a naturally occurring 1- O -alkylglycerol, has garnered significant attention due to its wide biological activities. To enhance its aqueous solubility, the complexation with sodium caseinate (NaCas) was investigated. Results showed the SA-NaCas complex, optimally formed at a 1:4 mass ratio, yielded a nanoscale dispersion with enhanced surface hydrophobicity, reduced dynamic surface tension, and superior emulsifying indices compared to NaCas alone. Fluorescence spectroscopy elucidated the interaction between SA and NaCas as a spontaneous process, mainly driven by hydrophobic forces. The binding constant and Gibbs free energy change were 1.17 × 10 3  L/mol and − 18.09 kJ/mol at 308 K. Molecular docking revealed that hydrophobic and hydrogen bonding interactions were the main forces driving the binding of SA to the α- and β-casein components of NaCas. The SA-NaCas nanocomplex not only enhances SA's water solubility, but also can be used as an effective nano-delivery system with better physicochemical properties than NaCas.