Fig. 5
From: Validation and calibration of a novel GEM biosensor for specific detection of Cd2+, Zn2+, and Pb2+
Fluorescent intensities (RFU) of E.coli-BL21-CadA/CadR-eGFP cells plotted against heavy metal treatment concentrations (ppb). The Y-axis represents the fluorescent intensity in RFU, while the X-axis represents the concentration of heavy metals in ppb. The plots for Cd2+, Pb2+, Zn2+, and Ni2+ are shown in blue, orange, ash, and yellow, respectively. The data were normalized to untreated E.coli-BL21-CadA/CadR-eGFP cells and wildtype E.coli-BL21. Error bars represent the standard error mean derived from three separate treatments. A single asterisk (*) represents a P value less than 0.05 (P < 0.05), indicating statistical significance at the 0.05 level. Double asterisks (**) represent a P value less than 0.01 (P < 0.01), indicating statistical significance at the 0.01 level. Triple asterisks (***) represent a P value less than 0.001 (P < 0.001), indicating statistical significance at the 0.001 level