A natural quercetin-based fluorescent sensor for highly sensitive and selective detection of copper ions

Abstract

A natural quercetin-based fluorescent sensor for highly sensitive and selective detection of copper ions has been studied. The quercetin fluorescent sensor after binding to Cu²⁺ ions in pH 7.40 buffered solution showed a quenching of fluorescence emission intensity. The binding constant value was obtained as 3.56 × 10⁷. The sensor can be applied to the quantification of Cu²⁺ ions with a linear range of 2.0 × 10⁻⁷–3.0 × 10⁻⁶ mol L⁻¹ and a detection limit of 1.0 × 10⁻⁷ mol L⁻¹. The sensor showed high selectivity toward Cu²⁺. As a result, the proposed fluorescent sensor was successfully applied for determination of Cu²⁺ in water samples.