Development of Fluorescent Turn-On Sensor for Selective Detection of Cu~(2+) in Aqueous Solution

摘要

Cu~(2+) is one of the most essential metal ions in biological systems, since it plays an important role in numerous biological processes and can induce various disorders, including some neurodegenerative diseases such as Alzhemer's, Prion, and Parkinson's diseases. Thus, quantifying the amount of Cu~(2+) in a systems crucial for studying the pathological roles of Cu~(2+) in living systems. The development of fluorescent sensors for Cu~(2+) has received much attention in last decade because of their simplicity and high sensitivity. In addition, fluorescent sensors can offer the potential application in real time detection in living systems with high spatial resolution that is difficult or impossible to obtain using conventional techniques such as atomic absorption spectroscopy and inductively coupled plasma mass spectroscopy. In particular, the development of a fluorescent turn-on sensor is critical to enhance detection sensitivities. Although there have been reports on fluorescent Cu~(2+) sensors, fluorescent turn-on sensors are still relatively rare because the paramagnetic nature of Cu~(2+) (3d~9) tends to quench the fluorescence. Recently, several groups have proposed copper promoting reactions including hydrolysis, oxidative cycli-zations of thiosemicarbazone to develop fluorescent turn-on sensor.