Nitazoxanide and azithromycin for the early treatment of COVID‐19: A multi‐spectroscopic, biochemical and computational drug–drug interaction study

Herein, we present an experimental and theoretical drug–drug interaction study between nitazoxanide (NTZ) azithromycin (AZT) in aqueous solution. Interaction was studied by using UV/Vis, fluorescence, attenuated total reflectance-fourier transform infrared (ATR-FTIR), circular dichroism (CD) spectroscopy, while molecular docking studies were performed to establish the computationally. A bright yellow color observed when two drugs interacted, giving a hyperchromic band at 420 nm. The rate of absorbance linearly increased increasing drug concentrations time-dependent manner. Stability complex (i.e., NTZ: AZT) measured variable temperatures (25–80°C), pH (5.0–10.0) ionic strength (0.05–2.0 M NaCl), not only proved stable but also retained antimicrobial potential with reduced cellular toxicity. Mole ratio Job's method continuous variations used binding stoichiometry found be 2:1. calculated constant (kb = 8,400 M−1) Gibb's free energy (ΔG° −22.4 KJ/mol) suggested energetically favorable interaction. FTIR spectra AZT comparison alone revealed significant which nicely complemented studies. successfully demonstrated presence carrier protein HSA spiking real samples human plasma urine.