Amperometric determination of sodium nitrite by a microbial sensor

✍ Scribed by Isao Karube; Tadashi Okada; Shuichi Suzuki; Hiroshi Suzuki; Motohiko Hikuma; Takeo Yasuda

• Publisher: Springer
• Year: 1982
• Tongue: English
• Weight: 474 KB
• Volume: 15
• Category: Article
• ISSN: 1432-0614
• DOI: 10.1007/bf00499519

✦ Synopsis

A microbial sensor was prepared to determine sodium nitrite. This microbial sensor consisted of immo-bilizedNitrobacter sp. and an oxygen electrode. When a sample solution containing sodium nitrite was tested, nitrite was changed to NO2 gas in the buffer (pH 2.0) and the current of the electrode decreased with time until a steady state was reached. The steady state current was attained within 10 min and the maximum decrease in current was obtained at 30 ~ and pH 2.0. A linear relationship was observed between the current decrease and the sodium nitrite concentration below 0.59 mM. the minimum sodium nitrite concentration that could be determined was 0.01 raM. The current decrease was reproducible (5% relative error). The current output of the sensor was almost constant for more than 21 days and 400 assays.