Abstract:Microbial biochemical oxygen demand (BOD) sensor is a kind of equipment for rapid detection of organic pollutants in water samples. The immobilized microorganisms is the heart of a microbial BOD sensor, which has great influence on the performances of the sensor like stability, response time, service life, linear response range as well as the practical apply range. Biofilm-type BOD sensors were widely studied and applied for their advantages such as simple structure, high sensitivity and short response time compared with other types of microbial BOD sensors. This article provides an overview on the application of immobilized microbes in biofilm-type BOD sensors. The principles, properties and applications of typical immobilization methods were summarized. Particularly, a range of frequently-used and potential immobilizing carriers were detailed. The relationships between characteristics of the carriers and the performances of sensors were analyzed, the microorganisms applied in this field were reviewed. Furthermore, the application and commercialization of biofilm-type BOD sensors were introduced, the pros and cons of varies types microbial BOD sensors were compared. Finally, unsolved problems of immobilized microbes in biofilm-type BOD sensors and its trend of development were discussed.
