An Electrochemical Dopamine Sensor with CMOS Detection Circuit

This paper presents the use of interdigitated microelectrodes as the platform for electrochemical sensing of the neurotransmitter dopamine. Gold electrodes with gaps ranging between 3 mum to 7 mum are fabricated by the lift-off technique. The reduction and oxidation potentials for dopamine are determined by voltammetry using the fabricated microelectrodes. A CMOS sensing circuit is used to amplify the electrochemical current produced by the working electrodes. Experimental result shows that for a dopamine concentration of 10 muM, the measured current value is 11 pA.