Notably, the immunosensor achieved simultaneous detection of two bladder cancer biomarkers (Apo-A1 and NMP 22) with a wide linear range spanning over five orders of magnitude and low detection limits of 0.3 pg/mL (Apo-A1) and 0.7 pg/mL (NMP 22). Here, APOA1 is linked to urinary bladder carcinoma.