A primary antibody is an immunoglobulin that specifically binds to a particular protein or other biomolecule of research interest for the purpose of purifying or detecting and measuring it. Primary antibodies are developed as polyclonal or monoclonal antibodies using mouse, rat, rabbit, goat, and other animal species as hosts. They are produced and supplied in various forms, ranging from crude antiserum to antigen-purified preparations. Primary antibodies for frequently researched targets are also available conjugated to fluorescent dyes or biotin.
The Invitrogen antibody portfolio is expanding—see the latest additions
We are continuously updating our Invitrogen primary antibody portfolio with advanced verified products for use in flow cytometry, IHC/IF/ICC, western blotting, ELISA, and other applications. Checkout our latest antibody highlights:
A specific and efficient antibody for histone H3K27ac
Histone proteins act as spools around which DNA is wound to form the nucleosomes in chromatin. Modifications to these histones can promote or antagonize transcription. One such modification is acetylation of lysine 27 on histone 3 (H3K27ac), a key marker of enhancer activity.
Enhancers are short regions of DNA far from the transcriptional start site that transcription factors bind to. They promote transcription by looping interactions. H3K27ac serves as a marker for active enhancers, and chromatin immunoprecipitation (ChIP) is a common application for examining active enhancers; therefore, it is crucial to have a highly efficient and specific antibody to H3K27ac.
The SNAP-ChIP method (EpiCypher) is robust and evaluates the specificity of antibodies in a ChIP experiment. It entails spiking in recombinant nucleosomes to test the antibody’s ability to pull down the modification of interest, and it determines if the antibody also recognizes off-target modifications. Using the SNAP-ChIP method, Invitrogen H3K27ac Monoclonal Antibody (Cat. No. MA5-23516) has been demonstrated to be an efficient antibody for immunoprecipitation with approximately 10% enrichment and little cross-reactivity with other modified nucleosomes.
Invitrogen Acetyl-Histone H3 (Lys27) Monoclonal Antibody is specific to its intended modification in ChIP. The SNAP-ChIP-K-AcylStat-Panel (EpiCypher, Cat. No. 19-3001) was used to analyze the performance of the Invitrogen H3K27ac antibody (Cat. No. MA5-23516) in ChIP. Specificity (left y-axis) toward each modified nucleosome in the SNAP-ChIP K-AcylStat panel (x-axis) was determined by quantitative real-time PCR (qPCR). The black bar represents antibody efficiency (right y-axis; log scale) and indicates percentage of the barcoded nucleosome target immunoprecipitated relative to input. All bars represent mean ± SEM.
Featured primary antibodies categories
Learn about our thousands of mouse, rat, hamster, rabbit, and other species of monoclonal primary antibodies.
Learn about our thousands of rabbit, goat, sheep, chicken, and other species of polyclonal primary antibodies.
Our broad portfolio of antibody conjugates—including Alexa Fluor dye and eFluor dye conjugates—is designed to help you answer complex cell biology questions, in less time and with less sample than other approaches.
Learn about our Invitrogen ABfinity rabbit monoclonal antibodies, developed by immunizing animals, screening for functionality, and then cloning the genes into high-level mammalian expression vectors.
Select a cell marker, organelle marker, or subcellular component antibody to identify and outline cellular structures and organelles by detecting proteins that are specific to them.
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For Research Use Only. Not for use in diagnostic procedures.