ZnO nanorods as immobilization layers for interdigitated capacitive immunosensors

•We attached ZnO nanorods to interdigitated capacitor microelectrodes.•The proposed micrometer approach is an advantage over nanometer immunosensors.•Antibodies were crosslinked to the ZnO nanorods which were stable during testing.•The immunosensors identified the target antigen by a decrease in the capacitance.•Maximum variation of the capacitance of the immunosensor was achieved at 6kHz.