b'Probing the membrane available and the antibody is produced in an expression system. Recombinant antibodies offer lot-to-lot consistency Most western blot analysis methods depend on the use ofand reproducible performance. To obtain antibodies with target-specific probes that are detectable via chemical tagsthe greatest specificity, you can affinity-purify the antibody or labels to measure the presence of specific proteins inusing the immobilized target molecule.biological samples. Antibodies are the most common type of probe because their binding affinity for specific proteinsSpecificity of primary antibodiesenables finding and detecting them in a complex sampleOnce an antibody is obtained, it is important to determine such as a lysate preparation of cells or tissues. However,if it is specific to its target. Antibodies that recognize antibodies are themselves proteins, and they are notproteins other than the intended one can give rise to specifically detectable in an assay system unless they aremultiple bands in a western blot, leading to challenges tagged for visualization (a primary conjugate) or are used inin data interpretation. Different types of specificity combination with a tagged secondary antibody. tests (thermofisher.com/antibodyvalidation) based on the target biology can be employed to determine Different types of chemical labels or tags can beantibody specificity.conjugated to antibodies to facilitate their detection and measurement by various methods. The most common tagsPrimary antibodies on thermofisher.comare enzymes and fluorophores. A number of advancementsWith hundreds of thousands of antibodies, our in reagents and instrumentation make these technologiesportfolio is validated* and cited for flow cytometry, more versatile and powerful. Chemiluminescence usingimmunohistochemistry (IHC), immunofluorescence enzymatic tags, such as AP and HRP, is the most common(IF), immunocytochemistry (ICC), western blotting, method of detection in a western blotting. However, the useenzyme-linked immunosorbent assay (ELISA), and of fluorescence technologies in western blot detection isother applications. With search filters, references, data rapidly advancing.images, published figures, and additional antibody supplier options, utilize the comparison feature at Primary antibody incubation thermofisher.com/antibodies to easily find the antibody The choice of a primary antibody for a western blot willyou need. To help ensure superior antibody results, depend on the target protein to be detected and whatInvitrogen antibodies are tested for specificity using a antibodies are available against that protein. A large2-part approach for advanced verification, testing for target number of primary antibodies are available commercially.specificity and functional application.Alternatively, a primary antibody may be custom-made to recognize the protein of interest. Both polyclonal and monoclonal antibodies work well for western blotting. Polyclonal antibodies are less expensiveDid you knowand less time-consuming to produce, and they often haveThermo Fisher Scientific offers custom antibody a high affinity for antigens. Monoclonal antibodies areservices to help you develop novel polyclonal, valued for their specificity, purity, and consistency thatmonoclonal hybridoma, or recombinant antibodies.result in lower background. Crude antibody preparations such as serum or ascites fluid are sometimes used for western blotting, but the impurities present may increase background. Recombinant antibodies are those for which the DNA sequence of the antibodys variable region is * The use or any variation of the word validation refers only to research use antibodies that were subject to functional testing to confirm that the antibody can be used with the research techniques indicated. It does not ensure that the product(s) was validated for clinical or diagnostic uses.Learn more at thermofisher.com/antibodies35'