Ibuprofen-based chemosensor for efficient binding and sensing of Cu2+ ion in aqueous medium

Abstract

An ibuprofen based molecular receptor R1 (N-[2-[(2-Hydroxy-benzylidene)-amino]-ethyl]-2-(4-isobutyl-phenyl)-propionamide) was developed for the detection of Cu2+ ion in aqueous medium by absorbance and fluorescence techniques. Binding constants (4.89–5.67 × 103 M−1) and detection limits (1.71–2.12 μM) showed significant sensing ability. SEM and PXRD techniques were employed to establish the complex formation between R1 and Cu2+ ion and also showed promising behaviour of nanomaterial. The competitive binding experiments showed the selectivity of Cu2+ ion in presence of other metal ions in aquoues medium. The reversibility studies for chemosensor R1 was investigated and EDTA used as restoring agent. The strong chelation through –N and –O atoms of receptor R1 enhance the change in color triggered selectively by Cu2+ ion and detected by colorimetric methods. The theoretical calculations were employed in order to confirm the experimental observations in the molecular frames.