Primary antibodies bind to antigens of interest but are not always labeled for direct detection. Secondary reagents target primary antibodies and are available with a variety of conjugations. This allows for use of a single primary antibody across multiple applications, which is particularly beneficial if there is no commercial availability of a primary antibody in a specific format. Secondary reagents can also be used to boost detection of low-expression antigens or markers, since polyclonal secondary antibodies can attach to a primary antibody at more than one site and amplify its signal. Find freedom in your experimental design with BioLegend’s secondary reagents validated for a range of methods, including flow cytometry, microscopy, western blotting, and ELISAs.