Influence of graphene oxide on the bile salts–ligand interaction: a spectroscopy study

Abstract

In recent times, much attention has been given to the study of the interaction between biomimetic assemblies with graphene oxide (GO), as the outcome of these interactions has a substantial impact on the biological and physicochemical properties of both the biomimetic assemblies and GO. Several applications of GO have been established over the years, and GO has the potential to be used as a biomedical material. In this article, we report the interaction of a red-emitting molecule, Nile blue A (NB), in the presence of four different bile salt aggregates as well as in the presence and absence of GO using various spectroscopic techniques. In the presence of different bile salts in water and varying concentrations of GO, NB undergoes a transition from the monomeric form to a J-dimer involving NB–bile salt interactions. The equilibrium between the H-dimer and J-dimer form of NB is also perturbed in the presence of GO and varying the concentration of bile salts. Raman spectroscopy establishes the fact that NB does indeed interact with the various functional groups present on the GO surface.