Multi-spectroscopic, molecular docking and molecular dynamic simulation evaluation of hydroxychloroquine sulfate interaction with caseins and whey proteins

This study investigated the interaction between hydroxychloroquine sulfate (HCQ) and caseins (CAS) or whey proteins (WP) by the means of various spectroscopic, molecular docking, and molecular dynamic (MD) simulation. The fluorescence spectrum revealed that CAS and WP interaction with HCQ resulted in static quenching due to the formation of HCQ-CAS and HCQ-WP complexes. The formation of complexes was also validated by fourier transform infrared spectroscopy (FTIR), circular dichroism spectroscopy (CD), X-ray diffraction (XRD), and scanning electron microscope (SEM). The FTIR and CD data revealed that HCQ binding altered the secondary structure of CAS and WP. Moreover, molecular docking and MD simulation were performed to analyze the formation of complexes, which compacted the CAS structure. Moreover, they also demonstrated that HCQ interaction with CAS and WP mainly involved hydrophobic interactions, with some hydrogen bonding and electrostatic attraction forces. This was consistent with the zeta potential, thermodynamic and FTIR analyses. In conclusion, the present study guides the construction of the CAS and WP as a drug delivery system for HCQ and helps us understand how HCQ interacts with food components such as milk proteins.