The ability to measure 7,000 proteins at once starts with exquisite specificity
See the exquisite specificity of the SomaScan® Assay
The SomaScan [Assay] also has a two-step approach to specificity that is sometimes forgotten by non-experts…between these two steps, the assay turns out to be quite highly specific.”
Why aptamers?
Shape specificity
By using uniquely modified DNA with hydrophobic functional groups, our SOMAmer® reagents achieve a greater degree of shape matching, enabling discernment between nearly identical proteins.
Slow off-rates
SOMAmer reagents are selected for slow off-rates when correctly bound to their intended target to ensure that correct proteins remain preferentially bound during rigorous washing.
Polyanionic competition
Polyanionic competitors are used to universally prevent rebinding of transient, non-specific interactions. There is no such universal competitor for antibodies.
X-ray crystal structure of a SOMAmer reagent bound to PDGF-BB.
Modifications to the bases are shown in purple, and the DNA backbone and unmodified bases are in teal.
Typical dissociation for a SOMAmer reagent
This graph shows the typical dissociation for a SOMAmer reagent over time, in this case targeting C3.