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Olink Proteomics—frequently searched as o-link proteomics or olink proteomics—is a high-throughput targeted proteomics platform designed to measure protein biomarkers across minute sample volumes. Developed by Olink Holding AB and acquired by Thermo Fisher Scientific, the system couples dual-antibody immunorecognition with genomic readouts. This guide explains how Olink works, who runs it, sample requirements, core facility costs, workflows, and alternatives for researchers and research administrators.
What it is
What is an Olink?
An Olink platform is an analytical system built upon proprietary Proximity Extension Assay (PEA) technology. Unlike multiplexed enzyme-linked immunosorbent assays (ELISAs), which encounter cross-reactivity when scaling antibody mixtures, Olink achieves high specificity by converting protein binding events into amplifiable DNA barcodes.
The assay proceeds through three distinct biochemical phases:
- Dual-Recognition Immunoreaction: Pairs of antibodies against distinct epitopes of the same target protein are each labeled with a unique, single-stranded oligonucleotide tag. When both antibodies bind the target protein, their DNA tags are brought into close proximity.
- Proximity Extension: Because the oligonucleotides share a complementary sequence overlap, proximity enables them to hybridize. DNA polymerase extends the hybridized strands, synthesizing a unique, double-stranded DNA amplicon (barcode). Single-antibody binding events do not achieve stable hybridization, eliminating background noise.
- Genomic Amplification and Readout: The DNA amplicons are amplified by PCR. Quantification is performed either via microfluidic real-time quantitative PCR (qPCR measuring cycle threshold $C_q$) on instruments like the Olink Signature Q100, or via Next-Generation Sequencing (NGS measuring read counts) on Illumina NovaSeq or NextSeq instruments.
The output is reported in Normalized Protein eXpression (NPX), Olink’s relative protein quantification unit on an arbitrary $log_2$ scale. Raw signals are normalized against an internal Extension Control spiked into every well, $log_2$-transformed, and adjusted across plates using pooled plasma controls. A one-unit increase in NPX corresponds to a doubling of relative protein concentration.
Who runs it and what it covers
Olink was founded in Uppsala, Sweden, commercializing proximity ligation research from Uppsala University. In July 2024, Thermo Fisher Scientific Inc. (NYSE: TMO) completed the acquisition of Olink Holding AB (publ) (Nasdaq: OLK) pursuant to a purchase agreement dated October 17, 2023, and a Schedule TO tender offer. The transaction valued Olink at approximately $3.1 billion, net of $96 million of acquired cash ($26.00 per share in cash). Olink operates within Thermo Fisher’s Life Sciences Solutions segment.
How much did Thermo buy Olink for?
Thermo Fisher acquired Olink for $26.00 per share in cash, representing a net enterprise value of approximately $3.1 billion, expanding Thermo Fisher’s presence in discovery proteomics.
The platform catalog covers three primary assay families:
- Target Series (qPCR Readout): Includes Target 96 panels (92 disease-focused proteins, such as Inflammation and Oncology) and Target 48 panels (45-plex cytokine panels with absolute quantification in $pg/mL$) running on microfluidic IFC chips.
- Explore Series (NGS Readout): Includes Explore 3072 (~3,000 proteins) and Explore HT (over 5,400 human proteins in a single reaction) using Illumina sequencing.
- Flex & Focus: Customizable panels of 15 to 21 targets for targeted cohort validation.
How much does Olink proteomics cost?
Olink assays are accessed primarily through institutional core facilities. Published FY27 rates (effective July 1, 2026 – June 30, 2027) from the Indiana University School of Medicine Proteomics Core illustrate standard per-sample fee structures:
- Target 96 (88-sample groups): $111.18 per sample (internal academic), $131.21 (external non-profit), and $177.61 (commercial).
- Target 48 (40-sample groups): $138.18 per sample (internal academic), $158.80 (external non-profit), and $215.55 (commercial).
- Reveal (NGS, 86-sample groups): $134.60 per sample (internal academic), $183.13 (external non-profit), and $237.40 (commercial).
- Explore HT (>5,400 proteins, NGS): $490.00 per sample (internal academic; $400.00 for cohorts >172), $612.00 (external non-profit; $535.00 for >172), and $796.00 (commercial; $713.00 for >172).
Per-sample core fees include sample plating, consumables, reagents, NPX calculation, pairwise comparison, and 5-year compliant data storage.
How to search or use it
What are the sample requirements for Olink?
Because PEA amplifies DNA tags, required sample volumes are minimal:
- Validated Matrices: Human EDTA plasma and serum are the primary validated matrices; CSF, saliva, urine, and cell lysates are also compatible. Samples on each plate must share the same matrix; never mix serum and plasma.
- Anticoagulant Requirements: EDTA is strongly preferred. Heparin must be avoided because it inhibits DNA polymerase.
- Volume Guidelines: Target 96 and Target 48 require 1 μL of biofluid per panel; Explore HT requires 2 μL. Core facilities request 10 to 30 μL per well in 96-well skirted V-bottom plates for robotic pipetting. Samples must be centrifuged, stored at -80°C, and shipped on dry ice. Recording pre-analytical preparation in an electronic lab notebook supports cohort tracking.
Operational execution follows six standardized stages:
- Plate Randomization: Randomize cohorts across 96-well plates using a randomized block design to maintain experimental reproducibility and prevent batch confounding. Reserve designated wells for negative and plate controls.
- Sample Preparation: Thaw biofluids on ice, centrifuge at 4°C, and transfer working aliquots into 96-well plates following an institutional SOP or protocol paper.
- Probe Incubation: Add Olink incubation mix containing pairs of antibody-oligonucleotide probes to 1 μL of sample. Incubate overnight (14–18 hours) at 4°C.
- Extension and Pre-Amplification: Dispense extension master mix. Thermocycling drives proximity-dependent hybridization and extension into DNA barcodes, followed by PCR pre-amplification.
- Instrument Readout: Load microfluidic Dynamic Array IFCs for qPCR on the Olink Signature Q100 ($C_q$ readout), or pool and sequence libraries on an Illumina NovaSeq or NextSeq system.
- NPX Processing and Archiving: Import raw data into Olink NPX Signature or NPX Map software to review QC flags, normalize to Extension Controls, and export calibrated $log_2$ NPX tables. When publishing, archive datasets alongside a data paper, provide a compliant data availability statement for reproducibility, and document descriptive metadata for datasets in open repositories.
Strengths and limits
Strengths
- High Specificity: Dual antibody recognition virtually eliminates non-specific background and cross-reactivity.
- Low Sample Consumption: Consumes only 1–2 μL of sample, preserving precious clinical biobank specimens.
- Broad Dynamic Range: Spans 10 orders of magnitude, capturing low-abundance cytokines alongside high-abundance circulating proteins.
- High Multiplexing: Measures up to 5,400+ proteins simultaneously on Explore HT.
Limits
- Relative Quantification: Standard NPX reflects relative fold-changes ($log_2$) rather than absolute molar concentrations ($pg/mL$), except on Target 48.
- Fixed Panels: Pre-manufactured panels do not permit ad-hoc substitutions of individual protein targets.
- Inhibitor Sensitivity: Residual heparin causes enzymatic failure during extension.
- Batching Constraints: Kits require full plates (40 or 88 samples) to amortize control well costs.
Alternatives
The table below contrasts Olink PEA against major alternative proteomic technologies:
| Platform | Detection Mechanism | Multiplex Depth | Sample Input | Quantification Mode | Primary Research Fit |
|---|---|---|---|---|---|
| Olink Proteomics | Dual antibody binding with Proximity Extension Assay (PEA) and qPCR/NGS readout | 45 to ~5,400 proteins | 1–2 μL plasma/serum | Relative ($log_2$ NPX); absolute on Target 48 | Targeted biomarker discovery, clinical trial profiling, and low-volume biobanks |
| SomaScan (SomaLogic) | Modified DNA aptamers (SOMAmers) with fluorophore array readout | ~7,000 to 11,000 proteins | ~50–65 μL biofluid | Relative (RFU) | Broad proteome screening and large-scale epidemiology cohorts |
| Multiplex Bead Assays (Luminex xMAP / MSD) | Capture antibody beads with fluorescence or electrochemiluminescence | 10 to ~50 proteins | 25–50 μL biofluid | Absolute ($pg/mL$) via standard curves | Targeted cytokine panels and routine preclinical validation |
| Untargeted Mass Spectrometry (LC-MS/MS) | Liquid chromatography coupled with tandem mass spectrometry (Orbitrap/TOF) | 500 to ~3,000+ proteins | 10–50 μL biofluid (depletion required) | Label-free quantification (LFQ) or isotopic tagging (TMT) | Unbiased discovery, novel protein identification, and PTM characterization |
Frequently asked questions
What is an Olink?
Olink is a targeted proteomics platform developed by Olink (Thermo Fisher Scientific). It uses Proximity Extension Assay (PEA) technology, combining matched antibody pairs with DNA tags to translate protein binding into quantifiable DNA barcodes measured by qPCR or Next-Generation Sequencing.
How much did Thermo buy Olink for?
Thermo Fisher Scientific acquired Olink Holding AB (publ) in July 2024 for approximately $3.1 billion net of acquired cash ($26.00 per share in cash), placing it within its Life Sciences Solutions segment.
How much does Olink proteomics cost?
Through academic core facilities, published FY27 rates from the Indiana University School of Medicine Proteomics Core range from $111.18 per sample for Target 96 (88-sample batches) to $400.00–$490.00 per sample for Explore HT (>5,400 proteins). Commercial rates range from $177.61 (Target 96) to $713.00–$796.00 (Explore HT).
What are the sample requirements for Olink?
Validated matrices include human EDTA plasma, serum, CSF, and cell lysates. All plate samples must share the same matrix, and heparin must be avoided. Assays consume 1 μL (Target 96/48) or 2 μL (Explore HT), though core facilities request 10–30 μL per well in 96-well plates for robotic pipetting.
Sources
- Thermo Fisher Scientific Inc., Thermo Fisher Scientific Completes Acquisition of Olink, Announces Commencement of Subsequent Offering Period (Official Press Release, read 2026-11-07).
- Wik, L. et al., Proximity Extension Assay in Combination with Next-Generation Sequencing for High-throughput Proteome-wide Analysis, Molecular & Cellular Proteomics, 2021; 20: 100168. PMCID: PMC8633680. DOI: 10.1016/j.mcpro.2021.100168 (read 2026-11-07).
- Indiana University School of Medicine, Proteomics Core Pricing: FY27 Service Schedule (Official Core Facility Rates, read 2026-11-07).
