The blocking peptide is the antigen we use for immunization during antibody generation so that we can create an antigen-specific antibody. You can use this blocking peptide as a negative control alongside other controls in an immunoassay to give some insight into antibody specificity, but not selectivity.

It’s important to note that the blocking peptide is not an effective control for use with live cells. If you need a control for flow cytometry, we recommend an isotype antibody control instead.

For more details, see our guide to blocking peptides.

We carefully choose the epitope for immunization, taking into account two main parameters: immunogenicity and specificity of the epitope.

Before immunization, we run a search to verify that the chosen epitope has maximum homology with other species and minimum homology among members of the same family or other proteins. After immunization and collection of sera, the antibodies are affinity-purified on immobilized antigens (the injected peptides).

This means you shouldn’t have to worry about your antibody cross-reacting with close members of the same protein family.

Affinity-purified rabbit polyclonal antibodies are mainly IgGs.

Our reagents are shipped as stable, lyophilized powders. Before opening, we recommend centrifuging the vial (e.g., 10,000 × g for 5 minutes) to ensure all material is collected at the bottom, as the pellet can be difficult to see.

To reconstitute, add your solvent directly to the vial to prepare a concentrated stock solution. Dissolve by gently tapping or rolling the vial. Avoid vigorous vortexing. For neurotrophins, pro-neurotrophins, and growth factors, we recommend avoiding vortexing entirely. Once dissolved, spin the vial down again and divide the solution into single-use aliquots for storage at -20°C.

For specific protocols, please refer to the individual product page and use our Molarity Calculator.

Solvent Selection & Guidelines

Venom Toxins: Usually soluble in pure water (ddH₂O) at high micromolar concentrations (0.1–1 mM). While they are typically compatible with any aqueous buffer, we highly recommend preparing the initial stock solution in pure water unless stated otherwise.

Neurotrophins & Growth Factors: Our general recommendation is to reconstitute with sterile water at a concentration of 0.1–1.0 mg/mL as a stock solution. For storage of dilute working solutions of specific proteins, we recommend adding a carrier protein (e.g., 0.1% BSA) to your buffer to prevent material loss due to protein adsorption. Always check the product-specific datasheet to ensure additives are compatible with your reagent.

Important Handling Notes:

We recommend preparing fresh working buffers before each use.
Avoid multiple freeze-thaw cycles to maintain biological activity.
Avoid heating peptides/proteins. Work at ambient room temperature and no higher than 37°C.