Low Molecular Weight Probe for Selective Sensing of PH and Cu 2+ Working as Three INHIBIT Based Digital Comparator.

A novel simple molecular chemosensor 2 was synthesized and examined for pH, cations and anions detection. At pH values higher than 10, probe 2 switches on a green emission where the excited state intramolecular proton transfer (ESIPT) is ceased. Also, the probe absorption spectrum shows a clear pH dependence, and the probe aqueous solution (ethanol/water = 1:2, borate buffer) responds selectively and sensitively through its fluorescence spectrum to the presence of Cu 2+ . Job's plot gave a 2:1 stoichiometry of Probe-2/Cu 2+ complex, which responds to the presence of S 2- and H 2 PO 4 - in aqueous solution (ethanol/water = 1:2, borate buffer) by its absorption and fluorescence spectra. In addition, probe 2 mimics a digital comparator based on three INHIBIT logic gates by different outputs using HO - and H + as inputs. Moreover, probe 2 also executes AND and NOT TRANSFER logic gates using Cu 2+ and S 2- as inputs.