[Biosensor of the reactor type based on Rhodococcus erythropolis HL TM-1 cells for determining 2,4-dinitrophenol]

A model of a reactor-type biosensor based on the Rhodococcus erythropolis HL PM-1 was developed for amperometric detection of 2,4-dinitrophenol (2,4-DNP). The effects of the matrix material (agar and calcium alginate gels, ceramic support, and cellulose powder) on the biosensor signal concentration dependence, detection time, and biosensor stability were studied. In case of bacterial cells immobilized on cellulose powder, the lower limit of 2,4-DNP detection was 20 microM and the time of single analysis, the biosensor recovery included, was 30-50 min. In the continuous detection mode, the biosensor response was maintained at a stable level without biosensor inactivation for ten days. The biosensor can be used as an element of a complex analytical system for detecting nitroaromatic compounds in samples.