Evaluation of an FIA operated amperometric bacterial biosensor, based on pseudomonas putida F1 for the detection of benzene, toluene, ethylbenzene, and xylenes (BTEX)

Recently, the development and optimization of a flow injection analysis (FIA) operated bacterial biosensor based on the aerobic catabolism of Pseudomonas putida ML2 was reported in the literature (Lanyon et al. 2004, 2005). By adapting information from these reports, we investigated whether operating parameters and procedures of the benzene biosensor could be directly applied to a new system based on a different bacterial strain for the detection of the whole benzene, toluene, ethylbenzene, and xylenes range. Cells of the investigated bacterial strain, Pseudomonas putida F1, were immobilized between two cellulose acetate membranes and fixed onto a Clark dissolved oxygen electrode. The P. putida F1 aerobically degrades benzene, toluene, and ethylbenzene (BTE) (Cho et al. 2000). The BTE biosensor in kinetic mode FIA displayed a linear range of 0.02–0.14mM benzene (response time: 5 min, baseline recovery time: 15 min), 0.05–0.2mM toluene (response time: 8 min, baseline recovery time: 20 min), and 0.1–0.2mM ethylbenzene (response time: 12 min,