Ion-selective microelectrode array for intracellular detection on chip

The design and fabrication of an Ion-Selective Electrode (ISE) array platform for in-vitro intracellular recording are presented. The platform is composed of two parts: 1) a glass chip with microchannels whose bottom part is patterned with a silver layer and 2) a silicon chip in with an array of 30 /spl mu/m long silicon nitride micropipettes with an inner diameter of 1.7 /spl mu/m long silicon nitride micropipettes with an inner diameter of 1.7 /spl mu/m are structured. The Ca/sup 2+/ selective membrane is based on the neutral carrier ionophore ETH 129. To be compatible with hepatocyte cell cultures the 24 ISEs are arranged in a 2/spl times/8 array with 150 /spl mu/m spacing and four additional electrodes located on both sides of the array at 300 /spl mu/m.