Determination of trace mercury in compost extract by
inhibition based glucose oxidase biosensor
(1. College of Environmental Science and Engineering, Ocean University of China, Qingdao 266003, China;
2. College of Environmental Science and Engineering, Hunan University, Changsha 410082, China)
2. College of Environmental Science and Engineering, Hunan University, Changsha 410082, China)
Abstract: A novel inhibition based biosensor of glucose oxidase(GOx) for environmental mercury detection was developed. An electropolymerized aniline membrane was prepared on a platinum electrode containing ferrocene as electron transfer mediator, on which GOx was cross-linked by glutaraldehyde. The response of the sensor was based on the current reduction in the electrochemical system by inhibition of mercury against GOx electrode. The detection limit of the inhibition-based sensor for mercury is 0.49 μg/L, and the linear response ranges are 0.49−783.21 μg/L and 783.21 μg/L−25.55 mg/L. The GOx membrane can be completely reactivated after inhibition, and remains 70% of the activity in more than one month. The sensor was used for mercury determination in compost extract with good results.
Key words: mercury; inhibition; glucose oxidase; biosensor; compost