Related Experiment Videos
Benzene analysis in workplace air using an FIA-based bacterial biosensor
Yvonne H Lanyon1, Giovanna Marrazza, Ibtisam E Tothill
1Cranfield Biotechnology Centre, Cranfield University, Silsoe, Bedfordshire MK45 4DT, UK.
Biosensors & Bioelectronics
|March 3, 2005
Summary
A novel bacterial biosensor using flow injection analysis (FIA) offers a portable and cost-effective method for detecting benzene in workplace air. This method provides accurate benzene measurements with minimal interference, complementing traditional gas chromatography (GC) techniques.
Area of Science:
- Environmental Science
- Analytical Chemistry
- Biotechnology
Background:
- Benzene is a common air pollutant found in workplaces, necessitating reliable detection methods.
- Conventional methods like gas chromatography (GC) can be expensive, complex, and lack portability.
- Development of rapid, cost-effective, and field-deployable benzene monitoring tools is crucial.
Purpose of the Study:
- To develop and validate a bacterial biosensor for determining benzene concentrations in workplace air samples.
- To assess the performance of the biosensor in terms of detection range, response time, and interference.
- To compare the biosensor's efficacy with established methods like gas chromatography (GC).
Main Methods:
- A flow injection analysis (FIA) system was designed incorporating immobilized Pseudomonas putida ML2 bacteria on a Clark dissolved oxygen probe.
- Benzene degradation by bacteria was measured via dissolved oxygen consumption, with air samples collected using charcoal adsorption tubes and desorbed with dimethylformamide (DMF).
- The biosensor's response to varying benzene concentrations and potential interfering compounds (BTEX) was evaluated.
Main Results:
- The biosensor demonstrated a linear detection range of 0.025–0.15 mM benzene, correlating to 3–16 ppm in air samples after a 60-min sampling period.
- A rapid response time of 6 minutes was achieved, and dimethylformamide (DMF) showed minimal interference and no toxicity to the bacteria.
- The portable FIA system showed good correlation with GC results and no interference from other BTEX compounds.
Conclusions:
- The developed bacterial biosensor is a promising tool for in situ monitoring of benzene in workplace air.
- Advantages include low operational costs, ease of use, and portability, offering a viable alternative to conventional GC methods.
- The biosensor exhibits specificity for benzene and compatibility with common sampling and desorption solvents like DMF.