Sensitive and Selective Fluorescent and Colorimetric Sensor for Ag⁺ Based on the Supramolecular Self‐Assembly in Semi‐Water

Abstract

Specific recognition of ultratrace levels of ions in semi-water using super-quicker methods is still a challenge for environmental monitoring. Herein we report a fluorescent and colormetric sensor (ZH) based on supramolecular self-assembly, whose structure was destroyed by the addition of ultratrace of silver ions. The process promoted either naked eye visible color changes or fluorescence intensity quenched in conjunction with a wide pH range. Systematic studies revealed very high selectivity (0.07 μmol/L) for silver ions, and other common cations, e.g., Hg 2＋ , Cu 2＋ , Cd 2＋ , Pb 2＋ had nearly no influence on the sensing behavior. This sensor also served as a multiple use of component in sensing materials by addition of I  into the mixture of ZH and Ag ＋ (about 5 times). What's more, ZH containing filter paper emerged distinct color and fluorescence changes upon exposure to silver (Ag ＋ ), which could be used as a portable method to undertake field testing for Ag ＋ .

Synthetic strategies of phenazine derivatives: A review

“…In recent years, our research group [92–113] has also committed to the research of phenazine and synthesized a series of other phenazine derivatives ( 148–168 ). As shown in Scheme 17, this product was firstly passed through the known 2,3‐diaminophenazine and benzaldehyde as fresh materials, using acetic acid as a catalytic amount mixed in anhydrous dimethylformamide at 85°C，and refluxed for 8 h. After purification, the yield was excellent, and it had remarkable thermal stability.…”