Fig. 4.

Correlation of measured IC₅₀ values between the newly developed LC–MS approach and the high-throughput fluorescence assay. The linear regression for inhibitors with IC₅₀ > 1 nmol L⁻¹ in the florescence assay is shown in grey. The LC–MS assay results for potent inhibitors (fluorescence assay ≤ 1 nmol L⁻¹) is shown enlarged in the inset, demonstrating that the fluorescence assay cannot distinguish among the most potent sEHI