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Primary Antibodies

Primary antibodies

Figure 1.Example of immunocytochemistry staining using a primary antibody, anti-beta-actin antibody.

Primary antibodies play a role in locating, detecting, identifying, and quantifying a target molecule. They directly bind to the antigen protein of interest. Primary antibodies can be produced as polyclonal, monoclonal, or recombinant antibodies.  

Explore our wide range of high-quality primary antibodies below.

Section Overview

Need help finding the correct antibody for your application?

Use our Antibody Explorer search tool to view and compare antibodies by clonality, application, species reactivity, conjugate, host species, and form.



Polyclonal Antibodies

Polyclonal antibodies are generated by injecting an animal with an antigen of interest. After several weeks, the animal’s serum is collected and can either be used directly or subjected to further purification to isolate antibodies. Polyclonal antibodies often recognize multiple epitopes, making them more tolerant of small changes in the nature of the antigen. 

Monoclonal Antibodies

Monoclonal antibodies are a laboratory-produced, homogeneous population of antibodies raised by the fusion of B cells with immortal cell cultures to produce hybridomas that can generate many copies of the exact same antibody. They recognize highly specific and unique epitopes with strong affinity and a reduced likelihood of cross-reactivity. 

Recombinant Antibodies

Recombinant antibodies are monoclonal antibodies produced by cloning antibody genes into expression vectors, without the use of hybridomas. These antibodies can be cloned from any species using suitable oligonucleotide primers. This technology helps avoid issues such as cell-line drift and mutations associated with classical hybridoma production. 

Explore more advantages of recombinant antibodies with our ZooMAb® Recombinant Monoclonal Antibodies.

Advantages and Disadvantages of Different Types of Primary Antibodies

Conjugated Primary Antibodies

Conjugated primary antibodies are often used for signal amplification and detection without the use of a secondary antibody. A primary monoclonal or polyclonal antibody can be directly conjugated to fluorophores, enzymes, or biotin. Different antibody conjugates exhibit different stabilities and require specific buffers and storage conditions to maintain their maximal activity over time.  

Primary Antibody Research Areas

Primary Antibodies for Cancer Research

Primary antibodies that detect abnormal proteins and tumor-associated antigens are valuable tools in cancer research. Some primary antibodies are used to block oncogenic pathways, stimulate antibody-dependent cellular cytotoxicity (ADCC), and activate complement-dependent cytotoxicity. These antibodies are crucial for studying tumor markers, tumor suppressors, invasion, metastasis, autophagy, apoptosis, and angiogenesis, offering insights into various aspects of cancer biology and treatment. 

Find recombinant antibodies specifically targeting hallmarks of cancer on our Studying Hallmarks of Cancer with Recombinant Antibodies page.

Primary Antibodies for Neuroscience Research

Primary antibodies play a vital part in studying nervous system physiology and pathology by allowing researchers to identify and analyze specific proteins and cellular markers. They are essential for investigating synaptic biology, as well as understanding neurodegenerative conditions such as Alzheimer’s disease and Parkinson’s disease. Additionally, these antibodies help explore neuroinflammation, which is a key factor in various neurological disorders. 

Primary Antibodies for Epigenetic Research 

Primary antibodies can also help explore the epigenetic processes that turn genes "on" and "off". DNA methylation and the post-translational modification of histones are among the major epigenetic factors.

Applications of Primary Antibodies

Primary antibodies are essential tools in a variety of laboratory techniques used to study proteins and their interactions. They enable precise detection, quantification, and analysis of specific proteins across different experimental techniques such as:

  • ELISA: A plate-based assay technique designed for detecting and quantifying soluble substances. It combines the specificity of antibodies with the sensitivity of simple enzyme assays.  
  • Western Blotting: Detect specific protein molecules within a mixture of proteins.  
  • Immunocytochemistry: For visualization of proteins or other antigens in cells using antibodies specifically recognizing the target of interest. 
  • Immunohistochemistry: Selectively identify antigens (proteins) in cells of a tissue section. 
  • Immunoprecipitation: Precipitate a protein antigen out of solution using an antibody that specifically binds to that protein. This technique isolates and concentrates a protein from a sample containing many thousands of different proteins. 
  • Flow Cytometry: Detect and measure physical and chemical characteristics of a population of cells. Light scattering patterns are used to determine the size and intracellular complexity of cells. 
  • Affinity Binding Assay: Measure the strength of the binding interaction between a single antigen and antibody. A lower number indicates a higher binding affinity. 



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