title: A rapid and sensitive p-benzoquinone-mediated bioassay for determination of heavy metal toxicity in water.
abstract: Determining and monitoring toxicity of chemicals in water are very important for human health and country security. Electrochemical measurement of respiratory chain activity is a rapid and reliable screening of the toxicity towards microorganisms. Here, we report a rapid and sensitive toxicity bioassay using p-benzoquinone as the artificial electron mediator and Escherichia coli as the test organism. Four heavy metal ions, Cu(2+), Ag(+), Hg(2+) and Co(2+), are tested as the model toxicants, and the corresponding 50% respiration inhibition concentrations (IC50) are determined to be 0.95, 8.14, 11.69 and 42.76 mg L(-1), respectively. Based on the IC50 values, the descending order of toxicity is: Cu(2+) > Ag(+) > Hg(2+) > Co(2+). The presented bioassay not only provides a good foundation for further toxicity tests using E. coli, but also the potential for expanding the technique to utilize other bacteria with complementary toxicity responses, thereby allowing use of the bioassay in a wide range of applications.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China.
authors.forename: Dengbin
authors.initials: D
authors.lastname: Yu
authors.forename: Junfeng
authors.initials: J
authors.lastname: Zhai
authors.forename: Daming
authors.initials: D
authors.lastname: Yong
authors.forename: Shaojun
authors.initials: S
authors.lastname: Dong
mesh_terms: D016227:Benzoquinones / Q000737:chemistry*; D001681:Biological Assay / Q000379:methods*; D004926:Escherichia coli / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D019216:Metals, Heavy / Q000633:toxicity*; D013696:Temperature; D013997:Time Factors; D018675:Toxicity Tests / Q000379:methods*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D016227:Benzoquinones; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D014867:Water; C004532:quinone