A Coordination Polymer for the Fluorescence Turn-On Sensing of Saccharin, 2-Thiazolidinethione-4-carboxylic Acid, and Periodate.

A luminescent 1D coordination polymer (CP) [ZnL(HO)]·HO (, HL = 1-(4-carboxyphenyl)-1-pyrazole-3-carboxylic acid) was prepared by a solvothermal method. shows excellent fluorescence properties and has an obvious fluorescence "turn-on" phenomenon for saccharin (SAC), 2-thiazolidinethione-4-carboxylic acid (TTCA), and periodate (IO). Between 0 and 60 μM concentration range of SAC, the fluorescence enhancement efficiency () of reaches 1.00 × 10 M with the limit of detection (LOD) of 90 nM. is the first CP-based sensing material for SAC detection. For TTCA detection, the is 2.73 × 10 M at the 25-80 μM concentration range, and the LOD is 33 nM, the lowest LOD among the sensors that detect TTCA at present. For IO ion detection, when the IO ion concentration ranges from 0 to 10 μM, the is 2.34 × 10 M and the LOD is as low as 39 nM. In order to better understand the sensing phenomenon, we also discuss in detail the sensing mechanisms for SAC, TTCA, and IO ions.