INTERACTION OF p- AMINO BENZOIC ACID (PABA) WITH IONIC AND NONIONIC MICELLES BY FLUORESCENCE

Micellar solubilization is a powerful alternative for dissolving hydrophobic compounds in aqueous environment. Fluorescence and absorption spectroscopy are the two techniques used to monitor the micellar solubilization studies of p-amino benzoic acid (PABA). PABA is an aromatic compound with acidic functional group, is non essential nutrient, used as a sunscreen. Externally, it prevents sunburn and skin cancer from UV light. The emission intensity of PABA is significantly enhanced in nonionic and anionic micellar media and decreased in cationic micellar media of different surfactants. The solubilizing action of the surfactant has also been determined by theoretical calculated spectral parameters like empirical fluorescence coefficient, quantum yield, molar absorption coefficient and stokes’ shift value. The fluorescence as well as the theoretically calculated spectral data have been used to characterize the heteroenvironment of the micelles in terms of their polarity, probe solubilization site and critical micellar concentration (CMC). This article briefly discusses the importance of surfactants in biological system model as well as the use of micelles in pharmacy as an important tool that finds numerous applications.