A ppb level turn-on fluorescence chemosensor for the detection of Zn2+

Zn has vital importance to the environment as well as human health. To regulate its dietary ingestion, it is important to monitor its presence in our food and environment, evoking more accurate and more sensitive ways to quantitatively determine its content in the environment. We herein present a squaraine-based chemosensor, namely DMPSQ, which has turn-on fluorescence response toward Zn2+ ion with good linearity, high selectivity and sensitivity down to 80 ppb. Theoretical calculations were also conducted to provide insight to the sensing mechanism and the spectroscopic properties of the compound.