A Ratiometric Fluorescent Probe Based on Copper Complex of Mercaptopyrimidine with Bifunctional Detection

Abstract In this paper, a new copper complex of Cu(dapymt)·4H2O (CuDpy) with strong and stable orange fluorescence was synthesized by using 4,6-diamino-2-mercaptopyrimidine (dapymt) as the ligand. Based on the excellent luminescent property of CuDpy, a bifunctional ratiometric fluorescent probe of CuDpy-CDs was constructed adopting CuDpy as the response fluorescent signal and blue-emitting carbon quantum dots (CDs) as the reference fluorescent signal. In the selective identification of anion and cation, CuDpy-CDs probe can specifically identify Ag+ and S2-. The detection limits for Ag+ and S2- were 1.88 μM and 0.16 μM, respectively, while the detection linear range of CuDpy-CDs for ions were 0-400 μM and 0-35 μM, respectively. In addition, a CuDpy-CDs portable sensing gel was fabricated which can monitor the approximate concentration of Ag+ and S2- in wastewater by the color change of fluorescence.