Hapten and peptide antigen conjugation services for immunogen preparation and antibody production

We offer multiple options for conjugating peptide antigens or haptens to immunogenic carrier proteins using strategies that optimize antigen presentation and antibody titer for custom antibody production services.

Our Targeted Antigen Display (TAD) Technology combines intelligent consideration of designed peptide structures, epitopes, and antigenicities with carefully selected combinations of conjugation methods to optimize antibody production with respect to intended assay applications. TAD Technology yields peptides that are conjugated in multiple, alternative conformations that mimic the presentation of epitopes in the native protein of interest based upon application. This process not only produces superior immunogens (i.e., higher antibody titer), but also results in antibodies that exhibit the best possible performance in different assay systems.

This is extremely important for generating antibodies that are assay-specific or can recognize changes in epitope conformation from one assay type to another. Although most of the individual carrier proteins and crosslinking strategies we offer represent well-established methods, TAD Technology provides unrivaled intelligence to the process of deciding among these individual options.


  • Crosslinking options—we are proficient with multiple conjugation chemistries and select combinations to pinpoint specific linkage sites on peptide antigens
  • Carrier proteins—we use KLH and other popular immunogenic carrier proteins, or we can use others that you specify
  • Assay-specific—we help select conjugation chemistries that best mimic epitope presentation in the intended assay method
  • Epitope analysis—we recommend ways to maximize epitope exposure within structural motifs and orientation to the termini
  • Design integration—together, our peptide design service (Antigen Profiler System), carrier protein selection, and conjugation method (TAD) maximize peptide solubility and linkage

Details and additional information

Carrier proteins

Researchers may select from the following list of common carrier proteins or submit to have another protein used.

  • KLH: keyhole limpet hemocyanin
  • BSA: bovine serum albumin
  • OVA: ovalbumin
  • THY: thyroglobulin

Conjugation chemistries

We do not recommend amidation or acetylation of terminal residues unless the peptide is being used for kinematic studies or a previous method is being imitated. The chemistries used solely or in combination to present optimal, assay-specific epitopes for TAD are as follows:

  • Glutaraldehyde: Links peptides to KLH through the N-terminus of the peptide with minor side chain reactions.
  • Carbodiimide (EDC): Attaches peptides through the C-terminus to KLH. Internal linkage to side chain carboxylic acids is controlled through time and linker concentration.
  • Maleimide: This chemistry is used when peptide sequences contain cysteines. An alternative (smaller) linker used instead of the traditional MBS. This minimizes the number of antibodies produced to the linker.
  • PNPI: Used to link through hydroxyl groups when certain conditions are met.
  • Dityrosine: Tyrosines can be used to cross-link peptides to form cyclic structures or conjugate one peptide to another species of antigen. Oxidative conditions are used to drive this highly specific, covalent bond.