A novel pyrene-based selective colorimetric and ratiometric turn-on sensing for copper

Detection of copper attracts important in most environmental and biological systems. In this study, a simple probe BisPyTSC containing bis-pyrene core was synthesized, and cation binding and sensing properties were studied using colorimetric and fluorometric detection. The research indicated that the specific ligand affinity for Cu²⁺ ions results in drastic color and spectral changes. According to the data obtained, while the peak intensity increases at 376 nm, the peak intensity decreased at 280 nm in the absorption spectrum of BisPyTSC and an increase in fluorescence intensity of BisPyTSC was observed in the presence of Cu²⁺ ions. The binding ratio of BisPyTSC to Cu²⁺ was found to be 1:1 according to Job's plot experiments. The binding constant was calculated using the Benesi-Hildebrand equation and found to be 3.26 × 10⁴ M^-1. Based on these concentration dependent fluorescence changes, the limit of detection (LOD) value was calculated to be 14.5 μM for Cu²⁺, which is the range of copper that should be in the blood (11.8-23.6 μM). As a result of all these studies, we can understand that BisPyTSC is a good selective candidate turn-on sensor that can be used for Cu²⁺ detection.