Vibrational and molecular properties of curcumin-natural deep eutectic solvent mixture using experimental and theoretical methods

The present work is aimed at analyzing the structural and chemical properties of Natural Deep Eutectic Solvent (NADES) comprising Menthol, Myristic Acid, and Curcumin, employing both computational and experimental methods. The enchanting pursuit of this theoretical study is to unravel the amicable interacting sites of these compounds using Density Functional Theory (DFT) at B3-LYP/6–31 + G (d,p) basis set. The intramolecular and intermolecular charge transfer between the hydrogen bond acceptors (HBAs) and hydrogen bond donors (HBDs) are affirmed by the NBO (natural bond orbital) study and AIM (atoms in molecules) analysis of the titled compounds. Through first-order hyperpolarizability parameters, the application of NLO onto the molecules supports the enhancement of the electron transfer. This paper also accounts for the interacting nature of CO, O–H, and C–H vibrational modes of the Men-Myr-Cur compound (Menthol + MyristicAcid + Curcumin) using Raman Spectroscopic and Infrared techniques. The theoretically computed Raman and IR vibrational wavenumbers are found to be in good agreement with the experimentally obtained values of the Raman, SERS, and FTIR. Moreover, the molecular docking analysis against the 7U5B receptor yields a remarkable binding energy of −6.15 kcal/mol, indicating the significant bioactive nature of the complex. Solubility and stability of Curcumin, both extract and standard samples in NADES are tested.