BOD微生物传感器的研究

Study of a BOD Microbial Sensor

本文采用夹层法,将异常汉逊酵母固定在氧电极的透氧薄膜与多孔醋酸纤维膜之间,构成一种流通式BOD测试系统。对新研制的电极的各种性能,包括各种理化因子对电极响应的影响作了系统的测试,发现电极电流差值与标准废水的BOD之间存在良好的线性关系,其线性范围为1～45mg/L,电极寿命长达180天以上,响应时间小于20分钟,电极测定重演性好,误差小于6%。

The biochemical oxygen demand (BOD) is one of the most important and widely used parameter in the measurement of organic pollution. The determination of BOD by conventional method takes 5 days, which is too long and complicated for the use in process control. In this paper, a microbial sensor consisting of immobilized yeast cells (Hansenula anomala) and an oxygen electrode was elaborated for the estimation of BOD. The structure of electrode was delicately designed and a flow-through system was set up in this study. The response time of biosensor is within 20 minutes. A linear relationship was observed between the relative current decrease and the BOD of the sample solution (GGA, model waste water) in the range of 1～45 mg/L. The life of the sensor is more than 180 days. The reproducibility of the sensor is quite good, the relative standard deviation is less than 6% at concentration of 20 mg/L BOD. Comparing with other sensors of same type both at home and abroad, many technical specifications of this sensor have been improved.