A three-dimensional platinum (Pt) microelectrode array embedded on a micromachined silicon (S) substrate (porosity of 13%, via hole diameter of 40 μm) has been developed. Electrodes are 35-μm wide and 20-μm high, spaced 200 μm apart and arranged in an elliptic geometry. Integrated within a microperfusion chamber, the devices were used for stimulation and recording experiments of hippocampal slice cultureS over a period of several days. | A three-dimensional platinum (Pt) microelectrode array embedded on a micromachined silicon (Si) substrate (porosity of 13%, via hole diameter of 40 μm) has been developed. Electrodes are 35-μm wide and 20-μm high, spaced 200 μm apart and arranged in an elliptic geometry. Integrated within a microperfusion chamber, the devices were used for stimulation and recording experiments of hippocampal slice cultures over a period of several days.