A glucose sensor with a plasma-polymerized thin film fabricated by dry processes

We have constructed a novel glucose sensor in which the enzyme is immobiliz ed on a plasma-polymerized film deposited on a patterned miniature electrod e. The films, which are formed by the glow discharge of a plasma of organic vapors, are extremely thin, adhere strongly to substrates, are mechanicall y and chemically stable, and are deposited in a dry process. As most miniat ure devices are fabricated using semiconductor process techniques, i.e., dr y processes, the plasma technique has enormous advantages for the fabricati on of microsensors. The samples were measured using amperometric methods an d this sensor was effective for glucose concentrations ranging from 0 to 30 mM with a detection limit of 1 mM. The sensor showed a short response time of 12 seconds.