Cu2þ-driven selective colorimetric sensing of iodide ions and AND logic gate using citrate-capped AgNPs

Abstract

A highly selective and sensitive colorimetric nanosensor driven by Cu2þ ion for iodide (I– ) ion was developed using citrate-capped AgNPs. This assay relied upon the distance-dependent optical properties of AgNPs where Cu2þ was employed as interlinking agent. In the simultaneous presence of I and Cu2þ, the system showed a color change from yellow to colorless that could be monitored using naked-eyes and UV–vis spectrophotometer. The nanosensor exhibited good iodide sensitivity with a detection limit of 0.24 μM. Further, the nanosystem was developed as an AND type logic gate with the inputs of Cu2þ and I.