A miniaturized device for wireless FSCV monitoring of dopamine in an ambulatory subject.

This paper reports on a miniaturized device for wireless monitoring of extracellular dopamine levels in the brain of an ambulatory rat using fast-scan cyclic voltammetry at a carbon-fiber microelectrode. The device comprises integrated circuitry for neurochemical recording fabricated in 0.5-microm double-poly triple-metal CMOS technology, which is assembled and packaged on a miniature rigid-flex substrate together with a few external components for supply generation, biasing, and chip programming. The device operates from a single 3-V battery, weighs 2.3 g (including the battery), and upon implantation successfully captures the effects of the psychostimulant amphetamine on electrically and non-electrically evoked dopamine neurotransmission in the caudateputamen region of an ambulatory rat's forebrain.