Introduction: Luminescent microbial biosensor is one of promising methods for biological protection of natural environment. This type of biosensor is a rapid, sensitive and precise tool and can be used for monitoring of environmental pollutants in very small scale (micro). In this study, luminescent bacteria Vibrio fischeri NRRL B-11177 has been used for design of quantitative and qualitative diagnosis kit of anionic surfactant Sodium dodecyl Sulfate (SDS). Methods: First, growth curve of V. fischeri was drawn to apply optimum time for experimental procedure. Then different amount of bacterial suspension (20, 50 and 100 µl) were used for optimization of SDS assay. According to information obtained, experiment was designed for determination of amount of bacterial response dose to various concentration of analyte. Results: Inhibition effect of SDS solution on luminescent intensity was investigated in concentration range of 2µM to1mM. Threshold detection of bacteria for SDS was 0.02 mM and the percentage of bioluminescence inhibition was determined after 5 and 10 min incubation time, 45% and 60% respectively. Increase of bacterial luminescence light emission in the presence of 2µM SDS solution was detected which could be because of Hormesis phenomenon. Discussion and conclusion: Results showed that bacterial growth curve elongate 30 h and 12-14 h bacterial culture could produce maximum luminescent light output. Also 20 µl of bacterial culture was giving the best response during experimental assay. In this condition, SDS could be detected in minimum concentration of 2µM using V. fisheri as bacterial luminescent biosensor

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