Slow Off-rate Modified Aptamer (SOMAmer) technology

Traditional antibodies are large affinity reagents (~150 kDa) that typically bind three‑dimensional structures on the surface of proteins that have triggered an immune response (ie, immunogenic targets). They are produced biologically either as monoclonal antibodies generated in cell culture to recognize a single protein epitope, or as polyclonal antibodies produced in animals that recognize multiple epitopes on the same protein.

SOMAmer Reagents, in contrast, are small, chemically modified aptamers (8—20 kDa) that also bind to three‑dimensional protein structures. Because they are fully synthetic, they provide consistent batch‑to‑batch performance. Their distinct chemistry also allows them to bind non‑immunogenic and epitopes currently not targeted by antibodies.

Together, these features make SOMAmer Reagents a versatile and reliable alternative to traditional antibody‑based tools.

SOMAmer‑based proteomics enables high‑throughput, cost‑effective workflows with > 10‑log dynamic range, femtomolar sensitivity, and scalable multiplexing, all with lower variability than traditional methods. This allows reliable detection of low‑abundance proteins without requiring any changes to the workflow and makes SOMAmer‑based proteomics a powerful and efficient approach for broad, reliable protein measurement at scale.

In contrast, mass spectrometry typically requires additional sample processing steps to improve coverage of lower‑abundance proteins.

Compared to antibody‑based approaches, SOMAmer‑based proteomics consistently delivers strong reproducibility (~5% CVs), even with expanded assay multiplexing.

The workflow takes about 2.5 days from sample to analysis, with less than 4 hours of hands-on time.

Each SOMAmer Reagent achieves its specificity through two key properties: high‑affinity binding to its target protein and a slow dissociation rate. These characteristics stem from the reagent’s unique chemical structure.

Before a SOMAmer Reagent is used in an assay, it undergoes primary validation, which includes pull‑down experiments and dose‑response assays to confirm that it binds selectively to its intended target. In addition, more than 70% of SOMAmer Reagents have supporting specificity data generated by independent researchers using orthogonal validation techniques, such as mass spectrometry.

SOMAmer Reagents are synthetic and can be consistently regenerated, ensuring lot-to-lot consistency and higher reproducibility than other affinity based methods.