CHEMBL3705897

Thio S Fluorometry Assay: The Thio S fluorometry assay as a primary screening method to identify tau protein aggregation inhibitors from our small molecule library. Aggregated tau fibrils were prepared in the presence of equimolar ratios of TauRD and heparin (10 μM each) in 20 mM Na-phosphate buffer, pH7.4. The reaction mixture was incubated at 37° C. with shaking (800-1000 rpm) for 22-24 hr (or for 3 days). In the Thio S inhibition assays, test compounds at 0, 0.1, 1, 10 and 100 μM were added at time 0 into the reaction containing TauRD and heparin. The same reaction mixture (+/− increasing concentrations of compounds) but without TauRD were also set up in parallel to serve as background controls. For all test compounds background fluorescence readings were very low, usually <5% of those of the TauRD-containing wells. For each compound, the IC50 was calculated using Prism version 5 software (GraphPad Software) by nonlinear regression [(Log [inhibitor] vs. normalized response; variable slope)].