Tris and bead interference

The table below shows results from a compound interference study. We tested a panel of 24 compounds in a QC assay using our AlphaLISA® toolbox bead products. The information below can be used for guidance as to whether Tris might interfere in assays involving particular bead products, and at what Tris concentration interference might occur. These data are derived from single experiments and should serve more as a guide rather than a precise value, as it is unlikely you will be using the exact same assay design as used to generate the data below. Interference concentrations may vary depending on the assay components. It is possible your assay will tolerate higher or lower concentration than what is shown.



Tested up to 0.5M
Catalog NumberProductNo effect (10%)50% loss% of inhibition at max conc
AL125Streptavidin AlphaLISA Acceptor Beads5.2E-024.5E-0153
AL126Protein L AlphaLISA Acceptor Beads1.5E-014.6E-0152
AL127Anti-FITC AlphaLISA Acceptor Beads9.9E-031.1E-0190
AL128 (biotin)Anti-6xHis AlphaLISA Acceptor Beads1.1E-034.3E-03100
AL128 (GSH)Anti-6XHis AlphaLISA Acceptor Beads7.2E-042.5E-0399
AL129Anti-V5 AlphaLISA Acceptor Beads7.7E-024.4E-0154
AL130Anti-mouse IgM AlphaLISA Acceptor Beads5.8E-041.2E-0183
AL131Anti-chicken IgY AlphaLISA Acceptor Beads4.9E-023.5E-0155
AL132Anti-sheep IgG AlphaLISA Acceptor Beads1.7E-012.2E-0157
AL133Anti-GFP AlphaLISA Acceptor Beads7.7E-071.6E-0290
AL134Anti-MBP AlphaLISA Acceptor Beads7.6E-031.3E-0171
AL136Strep-Tactin AlphaLISA Acceptor Beads5.9E-021.3E-0164
AS102Protein A Alpha Donor Beads3.3E-022.4E-0173
AS103Anti-FLAG Alpha Donor Beads1.6E-021.9E-0196
AS104Anti-mouse IgG Alpha Donor Beads9.5E-031.7E-0177
AS105Anti-rabbit IgG Alpha Donor Beads5.2E-024.5E-0153
AS106Strep-Tactin Alpha Donor Beads3.5E-03>0.532
AL900AlphaLISA TruHits kit 2 ug/mL7.6E-03>0.521
AL900AlphaLISA TruHits kit 20 ug/mL2.7E-02>0.529

Refer to the figure below for more detail as to what the values in the table above indicate. Please note that the figure is provided as a general example to explain how the values in our interference tables were determined. The table above indicates that an assay testing the effect of Tris using anti-6X His AlphaLISA Acceptor beads (with glutathione Donor beads) showed little effect on the assay signal at final Tris concentrations up to 0.72 mM. Tris did show a half-maximal inhibition of signal when used at a final concentration of 2.5 mM. When 0.5 M Tris was included in the assay, 99% signal inhibition was observed.

interferencetesting16_ASK.jpg
Figure: Key for how the values in our interference tables are derived. The “no effect” concentration was obtained by extrapolating the MAX - 10% MAX counts. Refer to the table above for actual interference values for each toolbox bead product.