Indigo Carmine-Cu complex probe exhibiting dual colorimetric/fluorimetric sensing for selective determination of mono hydrogen phosphate ion and its logic behavior.

A new selective probe based on copper complex of Indigo Carmine (IC-Cu2 ) for colorimetric, naked-eye, and fluorimetric recognition of mono hydrogen phosphate (MHP) ion in H2 O/DMSO (4:1v/v, 1.0mmolL-1 HEPES buffer solution pH7.5) was developed. Detection limit of HPO4 2- determination, achieved by fluorimetric and3 lorimetric method, are 0.071 and 1.46μmolL-1 , respectively. Potential, therefore is clearly available in IC-Cu2 complex to detect HPO4 2- in micromolar range via dual visible color change and fluorescence response. Present method shows high selectivity toward HPO4 2- over other phosphate species and other anions and was successfully utilized for analysis of P2 O5 content of a fertilizer sample. The results obtained by proposed chemosensor presented good agreement with those obtained the colorimetric reference method. INHIBIT and IMPLICATION logic gates operating at molecular level have been achieved using Cu2+ and HPO4 2- as chemical inputs and UV-Vis absorbance signal as output.