Spectroscopic investigations of aromatic heterocyclic compounds in reverse micellar media

In the present report, the effect of presence of aminopyridines on the microstructure of reverse micellar formulation in water/AOT/isooctane has been investigated. FTIR spectra reveal a change in the OH, CO and C–O–C stretching frequencies in the presence of aminopyridines. UV–vis absorption probe, acridine orange (AO) has been used to probe the microenvironment of the polar core and the interface. The results indicate that aminopyridines are placed between the water phase and the organic phase penetrating the interfacial layer at low water content values (ω) whereas with the increase in water content, it migrates to the core water. The polarity of the interface has been further probed by measuring the ET(30) values which increase with the increase in ω. Fluorescence measurements show the quenching capacities of the added aminopyridines. The formation of a nanosized emulsion even with the incorporation of aminopyridines has been confirmed by particle size estimations. The bell shaped conductivity curves obtained with increase in water content depict the delayed percolation threshold at lower surfactant concentrations.