Abstract
In this article, we describe a highly sensitive biosensing system, DRESSA, for detection of dioxin and dioxin-like chemicals. Tandem copies of the dioxin-responsive element (DRE) fused to a minimal viral promoter were subcloned into an expression plasmid upstream of a secreted alkaline phosphatase (SEAP) gene. When murine hepatoma cell line Hepa-1c1c7 was stably transfected with this construct, established sensor clones secreted SEAP following stimulation with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). A clone HeDS49 was found to be extremely sensitive; it secreted SEAP in response to TCDD in dose- and time-dependent manners, and the minimal detection limit was 100fM. To detect more than 6pM of TCDD, the whole assay time (from cell seeding to measurement of SEAP activity) could be reduced to 4h. Secretion of SEAP was induced selectively by other activators of DRE (3-methylcholanthrene, benzo[a]pyrene, and β-naphthoflavone) but not by activators of unrelated responsive elements. These data suggested that because of the rapidity, easiness, specificity, and high sensitivity of DRESSA, it is more suitable than currently available detection systems for dioxin and dioxin-like chemicals and would be of great advantage to high-throughput screening of these pollutants in environmental samples.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
