Comparison of two redox couples for AFM-SECM

Batch-fabricated conductive cantilevers that are merely insulated except for a small part at the tip, enable combination of atomic force microscopy and scanning electrochemical microscopy. This allows correlation of topographical features with a lateral, resolution of about 1 nm and functional features at a resolution <10 nm. Our interest is in proteins embedded in biological membranes. To study these several parameters must be optimized. E.g. the influence of the support on topographical and electrochemical data should be minimal. The choice of redox couple plays an additional role, since they have different sizes, charges, formal potentials and kinetic properties. In this paper two different redox molecules are compared in electrochemical experiments with our conductive cantilevers.