Duolink® - Protein Interaction Technology

The vast majority of proteins interact with other proteins for proper biological activity. Duolink enables you to detect, quantify and visualize protein-protein interactions, single target protein expression levels, and post translational modification events. This technology outperforms traditional protein detection methods by visualizing proteins in their native state through combining the selectivity of antibodies and sensitivity of nucleic acid amplification.

  • Visualize individual interactions without having to overexpress proteins
  • Detect and quantify weak and transient interactions at endogenous levels
  • Gain high specificity with dual binding of primary antibodies
  • Single molecule sensitivity due to signal amplification
  • Analyze using standard immunofluorescence instruments
  • Amenable to high throughput cell-based screens


 Choose your application

Evolve your immunodetection research with versatile technology by finding proteins that were previously undetected across multiple applications.

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Protein-Protein Interaction

Many important biological processes are determined by protein complexes of protein-protein interactions, including - DNA replication, transcription, translation, splicing, secretion, cell cycle control, signal transduction, and intermediary metabolism. The role and activity of proteins are often modified by interactions with other proteins. Research on how proteins interact with various components of the cell is driven by the fundamental interest in understanding disease pathways. Whether protein-protein interactions are transient or stable it is critical to measure the change. Using Duolink you can visualize stable, weak, and transient endogenous protein interactions.

To see what your protein interacts with, check out the STRING Database.

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Post Translational Modification

Interaction of proteins often depends on modification states of one or both proteins. Post-translational modifications (PTM) refer to covalent and generally enzymatic modifications of proteins during protein synthesis after its translation by ribosomes is complete. A few types of PTMs that modulate functional and structural proteomic research include – phosphorylation, glycosylation, acylation, sulfation, and ubiquitination. Historically analyzing PTMs required multiple technologies including gel electrophoresis, mass spectrometry, HPLC and immunochemistry. Duolink enables you to visualize endogenous modification events within fixed cells and tissues.

Learn more about Post Translational Modification HERE

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Low Abundant Proteins

Studying proteins in their native state is critical for true disease biology research. However, protein concentrations within a given sample can have a wide dynamic range. Traditionally, studying proteins in their native state resulted in having to over express the protein of interest, tagging, or genetically modifying the protein of interest. With Duolink you can detect endogenous protein levels of a single  protein or protein-protein interaction.

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Protein Localization

Protein localization involves the computational prediction of where a protein resides in a cell. Understanding the localization of proteins at a subcellular level leads to a better understanding of protein function, how they interact, and cellular signaling pathways. Traditional technologies allow the study of endogenous protein localization, which often show off-target binding and cross-reactivity with other proteins. Duolink enables a secondary antibody system to increase specificity and sensitivity of your protein of interest.


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Digital Quantification

Both cells and tissue images may be analyzed. The nuclei are automatically detected and cytoplasm size estimated, enabling single cell statistical analysis of expression levels in tissue or cell populations. Furthermore regions of interest can be defined, a feature of particular relevance when studying tissue samples. Raw imaging data can be imported directly from the four major microscope vendors (Olympus, Leica, Nikon and Zeiss) as well as tiff and jpg. The results data can easily be exported to Microsoft Excel for further evaluation.

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  1. Phizicky E. M. and Fields S. (1995) Protein-protein interactions: Methods for detection and analysis. Microbiol Rev. 59, 94-123.
  2. Stadler, Charlotte, et al. (2012) Immunofluorescence and fluorescent-protein tagging show high correlation for protein localization in mammalian cells. Nature. doi:10.1038/nmeth.2377"