Label-free sensing of pH and silver nanoparticles using an “OR” logic gate

Many natural phenomena are associated with the presence of two or more separate variables. We report here an “OR” DNA logic gate based on a luminescent platinum(II) switch-on probe for silver nanoparticles and pH, both of which may be considered putative indicators of pollution. The modulation of metal complex/double-stranded DNA complex phosphorescence by Ag+ and H+ was used to construct a simple, rapid and label-free method for the label-free detection of pH and nanomolar Ag+ ions and nanoparticles in aqueous solutions with high selectivity.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A DNA logic gate for silver nanoparticles and pH has been constructed. ► A platinum(II) complex produces a luminescence response to the analyte. ► The logic gate performs “OR” operations with a switch-on luminescent output. ► The system selectively detects nanomolar silver nanoparticles in aqueous solution.