Fabrication, prototype and use of the modular ion channel chip. (a) Assembly of the chip. The analyte can be added from the sample cell on the back of either compartment and delivered to the sensor element through agarose layered between the sample cell and the membrane. (b) A device prototype. (c) Signature blocks by the second messenger IP3 (500 nM) on the chip in a simulated intracellular conditions: 150 mM KCl, 2 mM ATP, 2.3 mM MgCl2, 10 mM Tris, 0.3 mM ATP, pH 7.4. This figure has been modified from reference71.