Proximity Extension Assay (PEA) technology

Innovation for protein biomarker discovery & protein analysis

The unique technology behind our Olink® Explore platform and  Olink® Target 96 and Target 48 panels enables high-throughput, multiplex immunoassays of proteins using minimal volumes of serum, plasma, or almost any other type of biological sample. Here we will show you how our technology delivers this scale of multiplexing and sample throughput without compromising on data quality or assay robustness.

Olink’s PEA technology – the movie

The short video below overviews the Proximity Extension Assay (PEA) technology that lies behind our Olink Explore and Olink Target 96/48 platforms, with NGS or qPCR readout, respectively. The animation explains how our innovative dual recognition, DNA-coupled methodology provides exceptional readout specificity, enabling high multiplex, rapid throughput biomarker analysis without compromising on data quality.

White paper

For a more extensive explanation of this technology, please see our white paper, “PEA – A high-multiplex immunoassay technology with qPCR or NGS readout“.

Instructional video of how to run an Olink Target 96 assay

Overcoming the specificity issues of multiplexed immunoassays

Each of the 96 oligonucleotide antibody-pairs contains unique DNA sequences allowing hybridization only to each other. Subsequent proximity extension will create 96 unique DNA reporter sequences which are amplified by real-time PCR. A limiting factor of multiplexed immunoassays is the antibody cross-reactivity which restricts the degree of multiplexing of most assays to below 10-plex. Cross-reactive events will not be detected with Olink’s panels since only matched DNA reporter pairs can hybridize to produce an amplicon for NGS or real-time qPCR. This allows for scalable multiplexing without loss of specificity and sensitivity (see figures below).

A) Conventional immunoassays: cross-reactivity due to unspecific binding of antibodies limits the degree of multiplexing.


B) Olink’s technology: unique DNA oligo sequences report only matched DNA-pairs (e.g. 1A+1B). Cross-reactive events are not detected.


Biomarker assays

~475 million

Protein data points generated


Publications listed on website


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