A Naked-Eye Colorimetric Receptor for Anions Based on Nitro Group Featuring with Benzimidazole Unit

摘要

A novel receptor based on nitro group featuring with benzimidazole unit (S2) was successfully synthesized and applied to the anion (CN~, F and H2PO4~-) recognition. The S2 changed its colour for light yellow to dark yellow on addition of the anions in DMSO solvent. The LOD and K_(ass) values determined by UV-visible titration was 2.8 × 10~(-6) M and 1.2 (± 0.25) × 10~6M~(-1) for CN~-ion; 1.14× 10~(-6)M and 2.5 (± 0.25) x 10~6M~(-1) for F~- ion; and 1.23 × 10~(-1) M and 6.25 (± 0.177) × 106 NT~(-1) for H2PO4~- ion, respectively.