Fluorescence quenching determination of iron(iii) using rhodamine 6G hydrazide derivative

Abstract

A fluorescent probe, a rhodamine 6G derivative (R6GD), has been designed and synthesized for the determination of Fe(III). In HAc–NaAc buffer solution, R6GD exhibits highly selective and sensitive response toward Fe(III) based on the fluorescence quenching mechanism of R6GD due to the heavy atom effect of I₃⁻ formed in the reaction between KI and Fe(III). Under the optimal conditions, the concentration of Fe(III) showed good linear relationship with the fluorescence intensity change of R6GD. The linear response range of Fe(III) (R² = 0.9923) was found from 0.1 to 6.0 μmol L⁻¹ with the detection limit of 0.05 μmol L⁻¹ of Fe(III). The recovery of the approach in the determination of Fe(III) in real water samples was 83.3–99.5%.