Physicochemical, Spectral and Computational Insight into Intermolecular Interaction between Hydralazine Hydrochloride and Aspirin in Presence of Normal Saline

ABSTRACT Hypertension remains a major risk factor for cardiovascular diseases, leading to worldwide mortality. To deal with hypertension and associated cardiovascular morbidity and mortality, the development of novel and targeted intervention strategies is urgently needed. Thus, this study investigates the drug-drug, hydralazine hydrochloride (HHC) - aspirin (ASP) and HHC/ASA-proteins (oxidative stress-responsive kinase-1 (OSR1) and Human serum albumin (HSA). interactions. Physicochemical, spectral, and computational methods were employed to explore the nature and strength of the intermolecular interactions. The density and speed of sound for HHC have been measured in 0.002, 0.006 and 0.010 m ASA in the presence of intravenous (IV) fluid, normal saline (NS). The structural behavior of drug-drug interactions in the presence of NS was obtained using temperature and concentration dependency of volumetric and acoustic parameters. Positive Φ v O and negative S v values suggest the dominance of strong HHC-ASA interactions in NS medium. The increasing trend in Φ K at the entire studied range of temperature and concentration signifies the presence of strong interactions among drug molecules. The characteristic shifts in absorption bands and vibrational frequencies in UV-visible and FTIR spectra confirmed the presence of H -bonding and other non-covalent interactions between HHC and ASA in NS medium. DFT results supported experimental results, suggesting enhanced stability upon interaction due to extra ionic and electrostatic contributions. The molecular docking analysis revealed the favorable binding affinities for both drugs with human serum albumin (HSA) and hypertensive target (OSR1 kinase), signifying potential pharmacokinetic relevance. Overall, the collective experimental and computational outcomes revealed strong intermolecular interactions between HHC and ASA in physiological saline medium.