Benzidine-based chemosensors for the selective detection of phosphate, carbonate and copper ions: Applications in water and food sample analysis and on-field detection kit

Abstract

In this work, benzidine-based chemosensors were synthesized. A<inf>5</inf>R<inf>1</inf> had a cage-like structure along with 2-OH binding sites for encapsulation of Cu2+, A<inf>5</inf>R<inf>2</inf> was found to bind with PO<inf>4</inf>3¯ and CO<inf>3</inf>2¯ ion; whereas A<inf>5</inf>R<inf>3</inf> was innocent towards any cations or anions. The LOD for A<inf>5</inf>R<inf>1</inf> with Cu2+ was found to be 2.63 ppm. A<inf>5</inf>R<inf>2</inf> detected PO<inf>4</inf>3¯ and CO<inf>3</inf>2¯ with limit of detections 4.13 ppm and 5.40 ppm respectively. The interference studies indicated that there was no other ion which could restrain the analysis. Job's Plots showcased the 1:2 binding of the receptors with the analyte ion(s). The practical applicability of the probes was demonstrated by on-field detection kit and test-strip fabrication with colour change chart. Logic gate formulation with active simulation governed by the reversibility studies envisaged the reversibility and reusability of the probe and its solicitation in making electric devices. Furthermore, spiking studies proved the application of the receptors for convenient analyte detection in real-life food and water samples. © 2024 Elsevier B.V.