Abstract

Monitoring of trace amount of toxic metal ions in aqueous and biological systems is vital because exposure to even low concentrations of toxic metal ions can have severe consequences on human health and the environment. Various synthetic methodologies are utilized to fabricate chemosensors that can specifically detect these toxic metal ions with high sensitivity. Recently, fluorescent sensors, particularly the rhodamine derivatives, have been considered as one of the most promising candidates for the recognition of metal ions owing to their attractive highlights. In this context, polymeric sensors bearing pendant rhodamine units have significant benefits over rhodamine-based small molecular sensors because of high-aqueous solubility, improved stability, signal amplification, easy fabrication into devices, etc. Eventually, the aforementioned factors have persuaded scientists to grow such novel polymeric sensors. This review aims to summarize the recent advancements (2011–present) toward pendant rhodamine-based polymeric sensors for the detection of copper (Cu²⁺), mercury (Hg²⁺) and iron (Fe³⁺) ions. The sensing mechanism of these polymeric sensors typically depends on the structural switch between non-fluorescent spirocyclic derivative and highly emissive ring-opened amide isomer. Consequently, we anticipate that this work can provide an extensive outline of key angles related to the planning of rhodamine-affixed polymeric sensors for the detection of toxic metal ions.

摘要

监测水系统和生物系统中痕量有毒金属离子至关重要，因为即使暴露于低浓度的有毒金属离子也会对人类健康和环境产生严重后果。各种合成方法被用来制造化学传感器，可以高灵敏度地特异性检测这些有毒金属离子。最近，荧光传感器，特别是罗丹明衍生物，由于其吸引人的亮点，被认为是识别金属离子的最有希望的候选者之一。在这种情况下，带有罗丹明悬垂单元的聚合物传感器比基于罗丹明的小分子传感器具有显着的优势，因为它具有高水溶性、更高的稳定性、信号放大、易于制造成设备等。最终，上述因素已说服科学家开发这种新型聚合物传感器。本综述旨在总结基于悬垂罗丹明的聚合物传感器在检测铜（Cu²⁺ )、汞 (Hg ²⁺ ) 和铁 (Fe ³⁺ ) 离子。这些聚合物传感器的传感机制通常取决于非荧光螺环衍生物和高发射性开环酰胺异构体之间的结构转换。因此，我们预计这项工作可以提供与用于检测有毒金属离子的罗丹明固定聚合物传感器的规划相关的关键角度的广泛概述。