FAQ

For the latest information and questions about the instruments compatible with Olink Explore, please contact our support team.

Olink Signature Q100 is required for detection and quantification. A PCR instrument verified to use reaction volumes of 100 µL with a heated lid is also needed for the extension step in the assay protocol.

For complete lists of required equipment and consumables for each Olink product, please contact our support team.

Generally, no. For our diluted panels we dilute your samples as a part of the analysis. However, if you are running samples of a matrix other than serum or plasma, we recommend discussing dilutions and in some cases protein concentrations or cell density (e.g. for lysates or cell culture supernatant) with your sales representative, or with our support team.

Olink offers two types of customized panels:

Olink Flex panels are highly flexible and made-to-order. They enable you to select and combine targets for up to 30 human proteins in one biomarker panel with results reported in absolute quantification (pg/mL) and relative quantification (NPX). Pick and choose from over 200 inflammation-related human proteins with 99% combinability in a broad mix-and-match library.

Olink Focus panels are available via custom projects with our R&D experts, and offer assays for up to 21 customer-selected proteins, with a choice of absolute or relative quantification.

For Target 96 and Explore products Olink uses relative quantification (NPX, arbitrary unit), so calibration curves aren’t needed for each run. However, in vitro standard curves for most of our assays during the validation of the panels, using recombinant antigen, most of them can be found on our website. For specific biomarkers, please contact our support team.

Note: These curves estimate the assay’s range and shouldn’t convert NPX results to absolute units.

For easier Data Analysis, Olink Proteomics has developed the NPX Signature software, which can be used for data generated using Olink Target, Flex or Focus products. This is an easy-to-use tool that lets you import, quality-control and normalize your Olink data, providing you with Normalized Protein eXpression (NPX) or pg/mL values (depending on the Olink product you have chosen) that can be used for further statistical analysis in the same software. For more information, please visit our Olink Data Science Service page.

Standard statistical analysis can be performed on NPX data without any further normalization or transformation. We offer tools to support statistical analysis or NPX data can be used in any existing statistical analysis pipeline. NPX data is relative, therefore NPX values across assays should not be compared.

Please see the publications list on our website. The list is updated regularly and includes links to either the online article citation page.

NPX, Normalized Protein eXpression, is Olink’s arbitrary unit which is in Log2 scale. It is calculated from Ct values and counts. For more information, refer to our white paper “Data normalization and standardization” which can be found on the Documents page.

A result file and an Analysis Report are shared via Olink’s data transfer portal. We can also provide customized delivery upon request, please contact our sales and support team.

Data is delivered in Parquet file format. Parquet is a free open source file format built to handle columnar storage data. The file cannot be opened in Microsoft® Excel. Olink recommends installing and using DBeaver to view, query and export Parquet data. If required Parquet files can be exported to CSV format. Data will be delivered via the Olink® Data Transfer application, an on-prem solution where data is transferred and stored within the boundaries of Olink’s environment. For any questions around Parquet file format or alternative methods of data delivery, please contact our support team.

With one sample prep line and 1-2 FTE, you can process 528 samples per week with Olink Explore 3072 and 2064 samples per week with Olink Explore HT. Note that this can vary depending on the instruments used for sample prep. For alternative scheduling, please contact our support team.

Limit of detection (LOD) is calculated separately for each Olink assay and sample plate and presented in the output data file. The LOD is based on the background, estimated from Negative Controls included on every plate, plus three standard deviations. The standard deviation is assay specific and estimated during product validation for every panel.

Olink does not run duplicates of samples on a regular basis unless required by our customers. Generally, the biological variation exceeds the technical variation, so customers often focus on using different samples rather than replicates. The majority of the assays in Olink panels have intra-CVs below 10%. Typical intra-CVs for each assay are presented in the validation data documents for each panel which can be found on our Documents page.

Evaluation of the potential endogenous interference from heterophilic antibodies, e.g. human anti-mouse antibody (HAMA) and rheumatoid factor, together with specific interfering substances (hemolysate, lipids and bilirubin) is performed during the validation of each panel, please view our Data Validation documents on the Documents page. No significant assay interference has been observed.

During assay development, an antigen curve with 2-fold serial dilutions is produced to show assay specificity, linearity, and to determine the lower and upper quantification limits (ULOQ and LLOQ, respectively), the Level of Detection (LOD) and the effects of having extra antigen in the assay (Hook effect). For determining sensitivity, which is reflected by the LLOQ, the antigens are diluted to an extent where no signal can be longer measured, and this is used to indicate assay sensitivity.

The LLOQ is dependent on many factors, including antibody affinity to antigens, the different epitopes and antibody can recognize on antigens, and other interferences from samples (e.g., when proteins are bound to another proteins). LLOQ can vary from one assay to another and thus the sensitivity varies between the different assays. This is presented in the Validation Data document for each panel, which are available on our Document page.

Our technology has a sensitivity, comparable to or better than ELISA assays, down to fg/mL. Each assay is thoroughly validated to measure physiological and pathological protein levels in EDTA plasma.

To reduce any technical variation in your results, Olink recommends that samples are randomized prior to analysis and that the results are intensity normalized.

When analyzing results from 2 or more studies analyzed at different time points, and where samples cannot be considered randomized between the studies, Olink recommends including bridging samples in each study. Selection of bridging samples, recommended number of bridging samples, and bridging methodology is detailed in Olink Analyze’s Introduction to Bridging Tutorial.

Proper sample randomization improves the power of a study and ensures that technical variation is not confounded with biological variation. For most studies, samples can be completely randomized across the plates. In the case of longitudinal studies, we recommend keeping samples from the same subject on the same plate to preserve the paired nature of the study and minimize technical variability between paired samples. For more information on plate randomization and instructions on how to generate and evaluate randomize plates, Olink Analyze offers a tutorial on plate randomization.

Our panels are validated using EDTA plasma and serum samples. A range of additional sample types are compatible with the technology, such as citrate plasma, heparin plasma, tissue and cell lysates, fine needle biopsies, micro-dialysis fluid, cell culture media, dried blood spots, synovial fluid, cerebrospinal fluid, plaque extract and saliva.

For more details about using different sample types, please contact our support team.

Please read the validation documents on the document page on our website.