Patent ID: 8309362

Claim:
A process for the preparation of a screen printed electrode modified with Prussian blue, characterised in that it comprises sequential deposition on the working electrode surface of said screen printed electrode of a solution comprising the Iron (III) or Iron (II) ion and at least one surface-active agent in an appropriate solvent and a solution comprising the ferrocyanide (II) or ferricyanide (III) ion and at least one surface-active agent in an appropriate solvent, said solutions having concentrations such as to obtain the formation of Prussian blue directly on the surface of the working electrode; wherein said solutions have equal concentration of between 20 mM and 2 M, and are deposited in equal volume of between 100 nL and 4 μL for an electrode surface between 0.314 mm 2 and 3.14 cm 2 ; after mixing of the two solutions, the mixture is left to rest for a period of between 2 minutes and 2 hours; the working electrode surface is then washed with a washing solution; the electrode thus modified are left dried at a temperature between 50° C. and 200° C.; and wherein said screen printed electrode has not undergone pre-treatment before said sequential deposition of the solutions.