Trace level Al3+ detection in aqueous media utilizing luminescent ensembles comprising pyrene laced dynamic surfactant assembly

Abstract

Easily synthesizable amphiphilic probes have been designed for the detection of Al³⁺ exclusively at mesoscopic interfaces. The surface charge of the surfactant assemblies and the fluidity of the lipid aggregates show pronounced effects on the extent of Al³⁺ detection. Excellent sensitivity has been observed specifically in the presence of anionic surfactants and the lipid membranes with more sol-like characteristics. Moreover, a variation in the modes of Al³⁺ complexation is observed on shifting from one regioisomer to another. For instance, the para isomer exhibits a 1 : 2 stoichiometry with the Al³⁺ ion, while for the ortho-isomer, it is a 1 : 1 interaction. Considering the excellent sensitivity of the probe molecule towards Al³⁺, the present system has been utilized for the estimation of soluble aluminum content in acidic soil samples as well as in pharmaceutical tablets. Low-cost paper strips are developed for rapid, on-site detection of Al³⁺ without involving advanced instruments or trained technicians. Finally, the bioimaging of Al³⁺ is achieved in cervical cancer (HeLa) cells.