Figure 1.

General mechanisms of biosensor for pollutants detection. The basic construction of biosensor contains sensing elements and signaling elements. The biological-sensing elements including DNA (aptamer), protein (enzyme), antibody, and whole-cell (bacteria) are able to recognize the environmental pollutants such as heavy metals and organic pollutants. The signaling elements would be triggered by sensing elements and produce the different signals such as fluorescence, luminescence, color, pH change, or electricity that could be measured or detected by the operators.