Custom Antibody Services

Look no further. Our custom antibodies are designed, purified, characterized, and supported by the best in the business.

Click here to learn about the advantages of Phospho's custom service.

IgG Custom Antibodies

Custom Polyclonal Antibodies that Work!

We will be with you through the entire process of making and testing your custom polyclonal antibody.

For a detailed quote of our custom polyclonal antibody production service, fill out the form at right or contact us at


Antigen Design

The crucial first step. Our scientists have more than three decades of experience in designing peptide antigens to maximize antibody specificity. For phosphospecific antibodies, this means carefully selecting the amino acids on either side of the phosphorylation site.

Learn more about our design process.

Phospho peptide antigen design

Peptide Synthesis

After we have designed your optimal peptide, it is time to synthesize! If we are producing a phospho-specific antibody for you, both the phospho and non-phospho peptides are made. We use both of these peptides in the purification and characterization steps in order to maximize the phosphospecificity of your antibody.


  • Conjugated to KLH for use as antigen for immunizations.
  • ELISA screens for reactivity
  • Positive sequential affinity purification

Non-phospho peptide

  • ELISA screens for phospho-specificity
  • Negative sequential affinity purification
Peptide molecule


Immunization and Bleed Protocol

The initial immunization protocol is performed on 2 rabbits. Bleeds are collected semi-monthly, and there are intermittent boosts with the antigen to further stimulate the immune response.



Antibody Purification

We do so much more than collect and send you serum from your rabbits. We screen the serum ourselves, looking for the highest titer bleeds. We then purify the antibody over affinity columns made with the immunizing peptide. Phosphospecific antibodies are isolated via sequential affinity chromatography using both phospho and non-phospho peptide columns.

Learn more about our purification methods.

Phsopho column purification
Non-phospho column purification

Antibody Characterization

After purification, we characterize the antibody in ELISA, and check for specificity. For phosphospecific antibodies, ELISAs are performed against both phospho and non-phospho peptides to determine the antibody's degree of preferential recognition for the phospho peptide.

We go one step further and test your antibody in Western blots. Many times, we have appropriate positive lysate already in-house. If we don't, you can choose to provide us with samples of your lysate or cells so that our team can work with you to characterize your antibody.

Learn more about our characterization.

ELISA plate characterization
After you receive your antibody for testing, we continue to work with you to optimize your signal and your success.

Contact us for a Custom Quote


The crucial first step in the development of custom-made phosphospecific antibodies is the selection and design of the immunizing peptide.



The only way to isolate the desired phosphospecific antibody is through sequential phospho and dephospho affinity chromatography.



Western blots are essential to truly establish the specificity of an antibody for the holoprotein of interest.