Microfabirated Clark-type Sensor for Measuing Dissolved Oxygen

This paper presents a microfabricated Clark-type sensor which exactly can measure dissolved oxygen in the cell containing solution. We designed and fabricated a microfabircated Clark-type sensor for measuring the oxygen respiration level of few cells. The microfabricated Clark-type sensor is composed of 3-electrodes on a glass substrate, a FEP (Fluorinated ethylene propylene) oxygen-permeable membrane, and PDMS (Polydimethylsiloxane) reservoir for storing few cells containing solution. The microfabricated Clark-type sensor was fabricated using MEMS technology. Thin-film Ag/AgCl was employed as a reference electrode and its durability was verified by obtaining a stable open circuit potential versus a commercial Ag/AgCl electrode for 2 hours. Response time, reproducibility and linearity of the fabricated oxygen sensor were examined by amperometry. The fabricated Clark-type sensor showed 40sec of 90% response time, reproducibility with 1.37nA standard deviation of 97.03nA mean in the full-oxygen state and 0.26nA standard deviation of 3.25nA mean in the zero-oxygen state, and an excellent linearity with a correlation coefficient of 0.994.