Glutathione AlphaLISA Acceptor 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 what buffer components might interfere with AlphaLISA assays using Glutathione Acceptor beads, and at what concentrations 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.



No effect (10%)50% lossTested up to% inhibition at Max
Glycerol%0.23.030%71
NitroprussideM7.2E-045.7E-030.1M99
CHAPS%0.130.53%52
Deoxycholate%0.0060.023%100
SDS%0.010.023%100
Triton X-100%>3>33%0
Tween 20%>3>33%0
TRIS (pH8.0)M2.0E-033.4E-020.5M90
2-MercaptoethanolM8.14E-045.0E-020.1M65
DTTM8.4E-052.8E-030.1M62
EDTAM1.9E-037.0E-030.1M90
EGTAM5.6E-049.8E-030.1M92
ImidazoleM6.3E-042.6E-030.1M100
Mg2+ (MgCl2)M5.2E-049.6E-030.1M80
UreaM>0.1>0.10.1M0
VanadateM2.2E-046.7E-040.1M100
CitrateM2.4E-032.7E-030.1M100
Adenosine (ATP)M2.8E-033.4E-030.01M98
GlycineM>0.01>0.010.01M0
NaFM>0.01>0.010.01M0
Complete Protease InhibitorXndnd1X99

The table above indicates that an assay testing the effect of DTT using Glutathione AlphaLISA Acceptor beads, streptavidin Alpha Donor beads, and biotin-anti-GST/GST probe showed little effect on the assay signal at final DTT concentrations up to 84 uM. DTT did show a half-maximal inhibition of signal when used at a final concentration of 2.8 mM. When 0.1M DTT was included in the assay, 62% 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.