Fig. 5: Responsivities of biosensors in the presence of interferents.

a Supernegative YFP series emission spectrum (ex. 280 nm) in the presence of equimolar (1 mM) amounts of Tb³⁺ or Al³⁺. Yellow and gray shading denote the fraction of YFP fluorescence attributable to Tb³⁺ placement and aluminum noise, respectively. b GFP−10 and YFP−31 biosensor responses to 1 mM of Tb³⁺ versus a 10-fold excess of contaminants (10 mM) found in mine drainage from the Virginia Canyon. 50 mM Tris-HCl at pH of 7. Error bars denote S.D. +/− the mean. Green and yellow shading represent the fraction of GFP and YFP fluorescence attributable to Tb³⁺ placement and aluminum noise, respectively. c Virginia Canyon (VC) and modified Virginia Canyon (mVC) interference of the GFP−10 ratiometric signal in the presence of 1 mM Tb³⁺. GFP−10 concentration of 0.1 mg/mL (~3.7 µM) in 50 mM Tris-HCl at pH of 7. d Virginia Canyon (VC) and modified Virginia Canyon (mVC) interference of the YFP−31 ratiometric signal in the presence of 1 mM Tb³⁺. YFP−31 concentration of 0.1 mg/mL (~3.7 µM) in 50 mM Tris-HCl at pH of 7. Experiments were performed in biological triplicate. Source data are provided as a Source Data file.