Figure 4.

The cAMP Difference Detector in situ (cADDis) sensor responses, in a 96-well assay, to several standard receptors, including the D₁ dopamine receptor (A), the endogenous adenosine receptor (B), and the endogenous β-adrenergic receptor (C), produced EC₅₀ values consistent with the literature. The cADDis sensor showed little sensitivity to DMSO (D). Addition of DMSO alone, at final concentrations of up to 5%, resulted in a barely detectable increase in fluorescence (red), while the subsequent addition of isoproteronol produced a consistent ~35% ΔF (green), which was a decrease in fluorescence because this is a downward going sensor.