FIG. 5.

Implementation of kinetic assay (▪). In enzyme assays associated with minimal or noisy signal changes (due to dim fluorophore or otherwise unfavorable assay chemistry or enzymology), the end-point method (▴) may simply preclude the use of these assays in HTS (concentration–response plot using raw signals in [A]). The boost in S:B afforded by performing kinetic measurement and computing the activity using the change in signal (concentration–response plot using normalized signals in [B]) transforms many of these weak signal systems into screenable assays. RFU, relative fluorescent units.