IL13RA2 and colorectal cancer: Amperometric detection of IL-13Rα2 by H2O2/hydroquinone (HQ) system revealed a wide dynamic concentration range (2.7–100 ng mL−1), with an LOD value of 0.8 ng mL−1, and can be applied for quick and selective determination of IL-13Rα2 in raw cell lysates from human colorectal cancer cells.