Luminescence in organized media and supramolecular interactions:physicochemical aspects and applications

Abstract

Natural cyclodextrins are an example of simple organic molecules, which are able to complex many different molecules and especially water-insoluble organic ones. This property caught early the interest of researchers involved in the field of drug delivery and soon new modified cyclodextrins appeared with improved solubility or complexing efficiency. Analytical applications aiming at the determination of fluorescent drugs followed and revealed that not only was their luminescence maintained, but that it was often enhanced. The present review begins with a short introduction devoted to the analysis of the forces involved at the molecular level in the complexing process and to the nature of the various complexes observed. It then focuses on the most typical results obtained in the field of luminescence enhancement following complexation of molecules of biological interest. It is shown that analytical applications always benefit from an improved sensitivity as a result of this enhancement. Extensions of the scope of the technique such as the induced emission of non emitting chromophores (retinoids) as well as the enhancement in micellar solutions are also reviewed.