Current arsenic analysis methods in groundwater samples rely on expensive apparatus, complicated procedures, and dangerous chemical reagents. Also, delays in detecting arsenic harm to public health, the environment, agriculture and food sectors. Therefore, in this study, a bioluminescent biosensor has been optimized and used to detect and measure arsenic concentration in groundwater. Optimum conditions for the appropriate performance of E. coli DH5α (pJAMA-arsR) were determined and the luminescent calibration curve was drawn. The optimization results showed that maximum luminescent light output could occur at the end of the logarithmic phase or the beginning of the stationary phase, the temperature of 37°C, and pH between 5.5 and 7 upon adding 10μl n-decanal (18mM). Increasing the duration of bacterial induction by arsenic leads to elevation of biosensor luminescent light yield. Functional stability of the biosensor with 20% glycerol (V/V) at -20°C was verified for at least six months. Luminescence reaction of the bacterial biosensor cells to arsenic concentration in the range of 0 to 90 ppb was promising (R2 = 0.948 by linear regression), but higher arsenic concentration had poisonous effect on biosensor cells. The modified Gompertz model derived here could successfully predict the bacterial biosensor growth under the optimum condition compared with experimental data. In this study critical challenges, such as technical and appropriate performance, are defined to interpret the bacterial biosensor’s true perspective to promote its broad adoption and usage. The work is concluded with closing remarks and potential perspectives to emphasize the importance of the bacterial biosensor, which could detect arsenic from a wide scope in real-time, quickly, and environmentally friendly signaling tool with high sensitivity and selectivity.

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