What is Primary Antibody?

Primary antibodies are immunoglobulins that bind to a specific antigen of interest, such as protein, peptide, small molecule. And, they are commonly unconjugated. A primary antibody can recognize and bind with high affinity and specificity to purify, detect, and measure the antigen. Using a variety of hosts, such as mouse, rabbit, goat, or chicken, primary antibodies are available as polyclonal or monoclonal relying on their applications.

Primary Antibodies

Types of Primary Antibody

To date, commercially available primary antibodies are produced by many methods, and these differences yield antibodies with unique characteristics that affect their suitability for different applications. There are two main types of primary antibodies, polyclonal and monoclonal, shown in Fig.1. A polyclonal antibody is derived from a collection of B cells and potentially recognize multiple epitopes on an antigen. By contrast, a monoclonal antibody is an antibody that produced from a single B cell and can recognize only a single epitope on an antigen.

Polyclonal and monoclonal antibodies. Fig.1 Polyclonal and monoclonal antibodies.

Applications of Primary Antibody

Primary antibodies can be utilized in numerous types of applications, including:

  • Western Blot (WB)
  • Enzyme-Linked Immunosorbent Assay (ELISA)
  • Analytical Cytology
  • Immunoprecipitation (IP)
  • Immunohistochemistry (IHC)
  • Immunofluorescence (IF)
  • Flow Cytometry (FC)
  • Chromatin Precipitation (ChIP)
  • Crystallography
  • Surface Plasmon Resonance (SPR)
  • Neutralization (Neut)
  • Others

Conjugations of Primary Antibody

The assay format of primary antibodies determines their application. For example, unconjugated or conjugated to a reporter molecule, such as an enzyme or fluorophore. Conjugated primary antibodies are useful because they can be employed to create a detectable signal. Detection can be visualized via color-generation, fluorescence, or others.

  • Fluorescent Dyes

Fluorescent conjugated antibodies can be used in many different techniques, such as FC, and IF. Table 1 is listed widely common fluorescent conjugations and their color.

 The fluorescent conjugations Table 1. The fluorescent conjugations.

  • Chromogenic and Biotin Labels

Antibodies can be conjugated to a label that offers chromogenic detection, including:

  1. Horseradish peroxidase (HRP)
  2. Alkaline phosphatase (ALP)
  3. Biotin

Chromogenic labeled antibodies are great options for ELISA, WB, and IHC.

Tips for Choosing Primary Antibody

  • Focusing on applications

Researches should select the best antibodies depending upon their objections and the applications of this antibody through searching literature, product reviews, and product-data sheets.

  • Host species

When selecting primary antibodies, species of animal in which the primary antibody was generated and whether it will be compatible with your application, these should be noticed at the beginning.

  • The type of antibody matters

A monoclonal or a polyclonal antibody? For some proteins, you couldn’t have a choice. However, if you do have a choice, choosing the right kind of antibody possibly promote the research. Table 2 is described as the advantages and disadvantages of poly- and monoclonal antibodies.

Type of antibody Advantages Disadvantages
Monoclonal antibody High homogeneity More expensive
High specificity More time to produce and develop
More sensitive  
Polyclonal antibody Inexpensive High chance of cross-reactivity
Quick to produce Batch-to-batch variability
High ability to capture the target protein  
Easy to couple with antibody labels  

Table 2. The advantages and disadvantages of poly- and monoclonal antibodies.

Find the Primary Antibodies You Need

For over two decades Creative Biolabs has developed primary antibodies in various formats that are of optimal quality, target specificity and flexibility. We have supplied the virology research market with high-quality primary antibodies targeted to various viral markers. You can browse our website or contact us to find the right primary antibody or reagent for your experiment.

At Creative Biolabs, we provide comprehensive types of primary antibodies for customers worldwide. Besides produced antibodies, we also offer viroantibody discovery, engineering and customized services to help our customers achieve their research goals. If you are interested in these services and antibodies, please get in touch with us for more information.

Inquiry Basket