Figure 10: An electrode surface confined redox group contributes to a substantial potential dependent interfacial charging that can be sensitively probed and frequency resolved by impedance derived capacitance spectroscopy, i.e. ECS approach. In utilising the sensitivity of this charging fingerprint to redox group environment one can seek to generate derived sensory configurations. Generally, exemplified through the generation of mixed molecular films comprising ferrocene and antibody receptors to clinically important targets, the surface engineered with the specific purpose to use Cr as transducer signal is very sensible for biosensoring. Reprinted with permission from J. Lehr, F. C. B. Fernandes, P. R. Bueno and J. J. Davis, Analytical Chemistry, 2014, 86, 2559-2564. Copyright (2014) American Chemical Society.