Inhibitor effects on molecular beacon-based mercury assays for tuning of detection range

•A series of inhibitors were investigated to modulate the detection response range.•Complementary DNA and cationic CPE functioned as an allosteric inhibitor.•Iodide and cyanide ions functioned as a depletant with a sequestration mechanism.•Fine-tuning of detection range with inhibitors was successfully reproduced in real samples.