Assay Method Information | |
| Radiolabeling of ThT and Radioligand Binding Assay |
Description: | Initial competitive binding studies using [3H]CG and synthetic Aβ(1-40) were conducted to determine if CG, ThS and ThT bound to the same site(s). It has been determined that ThS competed with [3H]CG for binding sites on Aβ(1-40), but ThT did not (see, e.g., FIG. 5). High specific activity [N-methyl-11C]BTA-1 (see Table 1) was then synthesized by methylation of BTA-0. Bindings studies were performed with [N-methyl-11C]BTA-1 and 200 nM Aβ(1-40) fibrils. The specific binding of [N-methyl-11C]BTA-1 was 70%. FIG. 5 (see the right panel) shows competition curves for Aβ sites by ThT, BTA-0, BTA-1, and BTA-2 using the [N-methyl-11C]BTA-1 binding assay. The Ki's were: 3.0±0.8 nM for BTA-2; 9.6±1.8 nM for BTA-1; 100±16 nM for BTA-0; and 1900±510 nM for ThT. Not only is the quaternary amine of ThT not necessary for binding to Aβ fibrils, it appears to decrease binding affinity as well. |
Affinity data for this assay | |
---|---|
If you find an error in this entry please send us an E-mail |