Abstract: In this paper，a fluorescent probe based on TMS-ethynyl triazolyl benzothiadiazole derivative （BTD）was developed for recognition of copper cation（Cu2+）and fluoride anion（F-）. Sensing behavior of this probe towards anions and cations was monitored by UV-visible and fluorescent spectroscopies in acetonitrile. Among tested anions，only F- induced a decrease in absorption band with a blue shift from 390 nm to 383 nm. Concomitantly，a fluorescence quenching with a blue shift from 496 nm to 488 nm. Among tested cations，Cu2+ led to a decreased absorption band with a red shift and a significant decrease in fluorescent intensity. Interestingly，the fluorescence emission of BTD was highly sensitive to a combination of Cu2+and F- in a sequence dependent manner.

Key words: benzotiadiazole, fluorescent sensor, fluoride anion, copper cation, ion detection