Mechanistic interaction of triflate based noscapine ionic liquid with BSA: Spectroscopic and chemoinformatics approaches

Abstract

In the present era, Ionic liquids (ILs) are showing great importance in many fields of research. Apart from those applications, researchers have grown their interest in pharmaceutical applications of ionic liquids. Proteins play a vital role in the study of various in vitro and in vivo studies to understand the action of a drug. A little disturbance induced by a drug in the microenvironment of proteins can alter their natural three dimensional structure. It has been observed that the interaction of ILs with blood proteins (BSA and HSA) is providing useful information in the manufacture of active pharmaceutical ILs and drug delivery. In the present study, an attempt was made to investigate the interaction between BSA (Bovine Serum Albumin) and [Pip-Nos] Triflate, a Noscapine (alkaloid) based ionic liquid, using UV–visible absorption spectra, fluorescence spectra, circular dichroism, and chemoinformatics studies. UV spectra showed a rise in intensity with a small red shift proving the BSA-IL complex formation. According to fluorescence spectra, static quenching of the BSA was observed on the addition of IL. The conformational changes of bovine serum albumin were analyzed with the help of CD analysis. The moderate binding was observed as a result of all the spectroscopic assays in correlation with molecular modeling studies. [Pip-Nos]OTf displayed optimal binding to the BSA protein with a molecular docking score of −343.71 kJ/mol. The molecular dynamics simulation study showed the stable binding of [Pip-Nos]OTf with BSA through RMSD 1–2.2 Å, Rg score of 26.1–26.5 Å and RMSF 0.4–7 Å. MM/PB (GB) SA binding energy calculations revealed the involvement of large binding energy along with a high static number of hydrogen bonds in complexation. These spectroscopic and chemoinformatics assays report the potency of [Pip-Nos]OTf and an important futuristic role in cancer therapeutics.