A calixarene–BODIPY fluorescent sensor for selective Fe3+ detection in environmental water samples: insights into static and dynamic quenching mechanisms
Abstract
A calix[4]arene-functionalized BODIPY fluorescent probe (Calix-BODIPY) was developed for the selective detection of Fe3+ ions in aqueous media for the first time. The integration of a calixarene recognition unit with a BODIPY fluorophore enabled efficient fluorescence signal transduction, resulting in a rapid “turn-off” response (∼10 s) toward Fe3+ ions with high selectivity over competing species. The sensor platform exhibited a linear response in the concentration range of 332–3537 µM, with a limit of detection (LOD) of 87.65 µM. Spectroscopic studies revealed that the sensing mechanism is governed by combined static and dynamic quenching processes. The applicability of the proposed system was validated through the determination of Fe3+ ions in tap and well water samples, yielding satisfactory recovery values (75.17–121.12%) without the need for complex sample pretreatment. Compared to nanomaterial-based sensors, the Calix-BODIPY probe offers advantages such as a well-defined molecular structure, operational simplicity, and high selectivity. These findings demonstrate that calixarene–BODIPY hybrid systems represent a promising platform for the development of practical fluorescent sensors for metal ion detection.