The design, fabrication and preliminary characterization of a test aimed at the development of Ion Sensitive Field Effect Transistors coupled with CMNOS (Complementary Metal gate Nitride Oxide Silicon) circuitry is reported. By this technology inexpensive single chemical sensors or arrays and multi-sensors with on-board signal conditioning for environmental and biomedical applications are being developed. The test chip contains three sets of test structures in order to evaluate the chemical sensor performance, to extract the CMNOS process parameters (e.g. SPICE parameters) and to test basic analogue circuit blocks to be used for the on chip interface electronics.