Arrays of electrodes coated with molecules and their production

A method of forming coatings of at least two different coating molecules on at least two electrodes, the method comprising:

• (a) providing an array of at least two individually-addressable electrodes,
• (b) allowing a layer of a masking molecule to adsorb onto all electrodes,
• (c) inducing electrochemical desorption of the masking molecule from at least one but not all electrodes to expose a first set of exposed electrodes,
• (d) allowing a first coating molecule to adsorb onto the first set of exposed electrodes, thereby generating a first set of coated electrodes,
• (e) exposing all electrodes, including the first set of coated electrodes, to a masking molecule to allow adsorption of the masking molecule onto all electrodes, including the first set of coated electrodes,
• (f) inducing electrochemical desorption of masking molecule from a second set of electrodes to expose a second set of exposed electrodes,
• (g) allowing a second coating molecule to adsorb onto the second set of exposed electrodes;
• wherein the first coating molecule and the second coating molecule each have a molecular weight greater than or equal to 800 Da;
• and
• wherein the masking molecule has a molecular weight less than or equal to 500 Da.