Control and blocking peptides for your immunoassay experiments

Ensure antibody specificity and assay reliability with blocking and control peptides from St John's Laboratory.

  • Blocking peptides confirm your antibody's target accuracy by competitively inhibiting off-target binding in Western blot or IHC.
  • Positive control peptides validate assay performance by confirming successful epitope recognition, particularly in ELISA or assay development workflows.

  • Together, they strengthen confidence in your ELISA, Western blot, or IHC results.

    Purchase blocking peptides with confidence

    Eliminate doubt. Confirm specificity. Get results you can trust.

      Designed to enhance the specificity of your immunoassay experiments, St John’s Laboratory offers a range of high-purity blocking peptides to support confident antibody validation in Western blot, IHC, and ELISA.

      • Validate Antibody Specificity: Pre-incubate your antibody with a matching blocking peptide to confirm that is binds specifically to your target protein.
      • High purity & epitope precision: Synthesised to exactly match your antigen’s epitope for accurate competition.
      • Reduce background & false positives : Use blocking peptides to distinguish between specific and non-specific signals in IHC and WB.
      • Rigorous batch QC: Every peptide undergoes thorough quality control to ensure reproducible performance.

      Ready to improve your assay reliability? Browse our full catalogue of blocking peptides today.

      Our blocking peptide products

      Blocking peptide targeting GPCRs

      The 5ht1a antibody specifically targets the 5HT1A receptor, which is crucial for serotonin signaling and neurological research.

      The 5HT1A Blocking Peptide serves as a valuable control for antibody specificity in Western blotting (WB) and IHC. It competes with or completely blocks the antibody, preventing it from binding to the receptor in experiments.


      Blocking peptides targeting tyrosine kinases

      The ABL1 antibody detects the ABL1 kinase, which is vital for cell growth and a key target in cancer research, especially leukemia.

      Use ABL1 Blocking Peptide to validate validate the specificity of the ABL1 antibody.

      Blocking peptide targeting neurological proteins

      To effectively investigate alpha synuclein in neurological conditions like synucleinopathies, precise tools are essential. Alpha synuclein blocking peptide (STJ504398) is specifically designed to be used with an alpha synuclein antibody.


      Enhance the specificity and reliability of your experiments by confirming accurate antibody binding — crucial for studies in synaptic function and neurodegeneration.

      Positive control peptides: Essential controls assay validation

      Our positive control peptides are indispensable for validating assay performance. Positive control peptides contain the same sequence as the immunogen used to raise the antibody, ensuring the antibody is capable of recognising its target epitope.

      Benefits of using positive control peptides:

    • Robust antibody validation: Confirm your antibody binds its intended target.
    • Reliable data interpretation: Ensure your ELISA, WB, or IHC assays are functioning properly. A successful signal from a positive control peptide provides definitive evidence that your assay can detect the antigen of interest.
    • Positive controls are critical benchmarks in experiments, ensuring the entire procedure functions correctly and is optimised. A positive outcome confirms the reliability of the method, validating that any negative results are authentic.

      How do positive control peptides work? For direct ELISA, the positive control peptide can be coated on the plate. Successful antibody binding to the peptide directly confirms the antibody's ability to recognise and bind to its specific epitope. This is particularly useful in assay optimisation or antibody development workflows.

      FAQs

      What are Blocking Peptides? A blocking peptide is a synthetic replica of the epitope of the target protein. When pre-incubated with an antibody, they competitively inhibit binding to that epitope in Western blot or IHC. This helps confirm antibody specificity by showing signal loss when binding is blocked.

      Why are positive controls essential? Positive controls are critical benchmarks in experiments. A positive control peptide contains the immunogen sequence for the antibody you are using. They confirm that your assay and antibody are functioning correctly. A successful signal from a positive control peptide means the assay can detect the intended epitope, validating the system. This ensures any negative result is meaningful and not due to assay failure.