Ionic liquid-based reverse micelles. Use of hydrogen–deuterium exchange as a tool for surfactant self-assembly characterization

•H-D exchange in the cation of the ionic liquid-surfactant bmim-AOT when it forms reverse micelles was studied by 1H NMR.•Results were compared with those found for bmim-AOT in D2O showing an inhibition larger than 500-fold in reverse micelles.•The H-D exchange in bmim+ when it forms reverse micelles reflects the properties of the micellar interface.•The analysis of H-D exchange in bmim+ is a useful tool to explore the properties of reverse micelles formed by this cation.