A vertically aligned nanotube (NT) array platform with peptide-modified ends is used for sensing metal ions in aqueous environments. The NT arrays were assembled on gold substrates and characterised using confocal Raman microscopy to confirm the electrode fabrication process. A copper ion selective peptide — GlyGlyHis was used as the sensing recognition element. Cyclic voltammetry was used to measure the sensor's electrochemical response of the bound copper and to determine the stability of the sensor. The sensor showed minimum interference from other species and was proven to be very sensitive, enabling detection in the nanomolar range.