A glucose sensor fabricated on glass substrate with glucose oxidase immobilized technique

In this paper, we propose a low cost optical biosensor and corresponding measurement system. The biosensor is constructed of the glass substrate and immobilized glucose oxidase (GOx) on it. The sensor is provided with reference and testing windows which are used to achieve the absolute phase variation measurement and minimize the side effect of the reduced activeness of GOx. The corresponding measurement system is based on reflection type circular heterodyne interferometry which provides high sensitivity and real-time detection. Based on the experiment results, the resolution of our method is better than 5 mg/dl for the measured range within 10 to 120 mg/dl.