A conducting polymer nanojunction sensor for glucose detection

This paper presents a glucose sensor using conducting polymer/enzyme nanojunctions and demonstrates that unique features can arise when shrinking a sensor to the nanometer scale. Each nanojunction is formed by bridging a pair of nanoelectrodes separated with a small gap (20-60 nm) with polyaniline/glucose oxidase. The signal transduction mechanism of the sensor is based on the change in the nanojunction conductance as a result of glucose oxidation induced change in the polymer redox state. Due to the small size of the nanojunction sensor, the enzyme is regenerated naturally without the need of redox mediators, which consumes minimal amount of oxygen and at the same time gives very fast response (<200 ms). These features make the nanojunction sensor potentially useful for in vivo detection of glucose.