Disposable copper random microarray sensor using toner masks: Fabrication and application

This work describes the fabrication and application of a disposable copper random microarray (DCRM) of electrodes. The DCRM was fabricated by deposition of two toner pattern masks on a copper substrate. In the first step, the mask layers were drawn using a graphical software and then printed on waxed papers. The first toner mask delimited the disc area (2 mm diameter) and the second toner mask (with 90% of black toner) defined the irregular distribution of the generated microelectrodes. The toner masks were heat-transferred to the copper substrate (with a diameter of 10 mm and a width of 25 mm) for 600 s in a thermal press heated at 120 °C. The proposed electrochemical sensor was applied for the amperometric determination of two analytes: hydrogen peroxide in real samples (oral antiseptic and dental whitening) at −0.2 V in phosphate buffer (pH 7.0) solution and acetylsalicylic acid (ASA) in pharmaceutical formulations at 0.6 V in 0.10 mol L−1 NaOH solution. The good results obtained with the DCRM demonstrated the successful application of this new sensor. The main advantages of the proposed manufacturing procedure are the simplicity, low cost of equipment and the high speed of production of microelectrode arrays on different substrates.