Fluorescent detection of multiple ions by two related chemosensors: structural elucidations and logic gate applications

Abstract

Two related chemosensors L1 and L2 display selective detection of multiple ions (Cu²⁺, Al³⁺, Cd²⁺ and S²⁻) as a result of minor variation of functional groups. Both chemosensors offer identical pyrrole-2-carboxamide fragments; however, they differ by the presence of either an ester (L1) or an acid group (L2) at a remote arene ring. While L1 shows selectivity towards the Cu²⁺ ion L2 is highly selective for Al³⁺ and Cd²⁺ cations as well as S²⁻ anion. A combination of studies (Stern–Volmer plots, detection limits and Benesi–Hildebrand fittings) displays the notable sensing abilities of both chemosensors. Both chemosensors were utilized to develop logic gate-based applications by considering multiple detection of assorted ions. Structural studies provide vital details about the mode of binding between chemosensors and cations. Simple synthesis, multi-stimuli response, fast response, solution visualization, and practical detection methods (filter paper strips and polystyrene films) suggest excellent sensing potentials of both chemosensors.