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.

Featured primary antibodies categories

Monoclonal Antibodies

Learn about our thousands of mouse, rat, hamster, rabbit, and other species of monoclonal primary antibodies.

Polyclonal Antibodies

Learn about our thousands of rabbit, goat, sheep, chicken, and other species of monoclonal primary antibodies.

Recombinant Rabbit Monoclonal Antibodies

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.

Conjugated Primary Antibodies

Discover and select primary antibodies that are directly labeled or conjugated with biotin affinity tags, fluorescent dyes (Invitrogen™ Alexa Fluor™ dyes), or reporter enzymes (HRP, AP).

Research Area Antibodies

Find and select primary antibodies for key markers and targets relevant to cancer research, stem cell research, neurobiology research, epigenetic studies, and more.

Control Antibodies

Find loading and isotype control antibodies for standardizing, normalizing and validating semi-quantitative western blotting and other immunoassay results.

Signal Pathway Antibodies

View menus and lists of primary antibodies specific to proteins of key signaling pathways, transcription pathways, and various phosphorylation or activation states.

Epitope Tag Antibodies, etc.

We offer a wide selection of primary antibodies specific to epitope and affinity tags, fluorescent dyes, and fusion proteins. For popular targets, conjugates to biotin, HRP, and fluorescent dyes are available.

Cell Marker Antibodies

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.

Flow Cytometry 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.

Fluorescent antibody-drug conjugates- a new potential for antibodies

This video demonstrates the dual labeling of a primary antibody. Watch how  to create a fluorescent antibody-drug conjugate and learn about its  application, beyond the basic function as protein detection.