Fluorescence is routinely used to monitor kinase inhibition in commercial assays. Occasionally fluorescent compounds can interfere with the fluorescent reading. To address this issue, the problematic data are usually truncated to improve the fit, however, this approach raises ethical and reproducibility concerns. Instead, it is suggested to adjust the fitting formula, to account for the autofluorescence of the compounds and improve the fit of the data compared with a naive approach. Finally, it was noticed that truncating the data can result in a small underestimation of the IC50 values and should therefore be used carefully.
Keywords: LanthaScreen; autofluorescence; fluorescent compound; kinase binding; small-molecule kinase inhibitor.