DPV tested the controls used in multifunctionalised AuNPs and determined whether the redox peaks of Cyt c and Zn Porph could be identified. As shown in Figure , the redox peaks for Zn Porph, Cyt c Ox, and Cyt c Red were all easily identifiable. However, only one peak was visible for Zn Porph, unlike in the results obtained in CV in which multiple peaks were shown. In the case of AuNPs and PBS, DPV did not show any redox peaks, except for a very small peak at ~1.0 V for 20 nm cit-AuNPs, which could potentially interfere with the DPV spectra of the 20 nm multifunctionalised Cyt c and Zn Porph, as a result no analysis was conducted in this region. CV measures the current response to a linearly increasing or decreasing voltage sweep. The differences in the experimental conditions can cause variations in the observed peak potentials, as the behaviour of the electrode surface may differ between the two techniques . For a reversible and fast, one-electron transfer, the expected peak-to-peak separation (ΔEp) is known to be 57 mV at room temperature for CV measurements. Still, this value is rarely discussed in relation to DPV due to the single potential sweep that is used in DPV unlike the cyclic potential of CV's . In the case of Cyt c, the ΔEp values for the Ox and Red forms were calculated from The peak potentials of Cyt c identified using DPV differ from those determined by CV, likely due to variations in the techniques.