The use of co-immobilization of Trichosporon cutaneum and Bacillus licheniformis for a BOD sensor.
The microorganisms Trichosporon cutaneum and Bacillus licheniformis were used to develop a microbial biochemical oxygen demand (BOD) sensor. It was found that T. cutaneum gave a greater response to glucose, whereas B. licheniformis gave a better response to glutamic acid. Hence, co-immobilized T. cutaneum and B. licheniformis were used to construct a glucose and glutamic acid sensor with improved sensitivity and dynamic range. A membrane loading of T. cutaneum at 1.1x10(8 )cells ml(-1) cm(-2) and B. licheniformis at 2.2x10(8) cells ml(-1) cm(-2) gave the optimum result: a linear range up to 40 mg BOD l(-1) with a sensitivity of 5.84 nA mg(-1) BOD l. The optimized BOD sensor showed operation stability for 58 intermittent batch measurements, with a standard deviation of 0.0362 and a variance of 0.131 nA. The response time of the co-immobilized microbial BOD sensor was within 5-10 min by steady-state measurement and the detection limit was 0.5 mg BOD l(-1). The BOD sensor was insensitive to pH in the range of pH 6.8-7.2.
Suriyawattanakul
L
L
School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Toong-kru, Bangkok 10140, Thailand.
Surareungchai
W
W
Sritongkam
P
P
Tanticharoen
M
M
Kirtikara
K
K
D001407:Bacillus / Q000378:metabolism*; D015374:Biosensing Techniques; D018914:Cells, Immobilized; D005947:Glucose / Q000032:analysis / Q000378:metabolism; D018698:Glutamic Acid / Q000032:analysis / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D010100:Oxygen / Q000032:analysis* / Q000378:metabolism*; D012680:Sensitivity and Specificity; D014250:Trichosporon / Q000737:chemistry / Q000378:metabolism*
D007220:Industrial Waste; D018698:Glutamic Acid; D005947:Glucose; D010100:Oxygen