Learn how to use this product The IBA Strep-tag detection system offers a choice between HRP- or AP-labeled Strep-Tactin for direct detection and non-labeled antibodies to be detected by a secondary antibody. Fast detection is possible with the Strep-Tactin conjugates whereas monoclonal antibody-based detection enables higher specificity. StrepMAB-Classic is a murine monoclonal antibody that detects Strep-tag®II and Twin-Strep-tag® fusion proteins in a highly selective manner. Applications include western blots, ELISAs, immunohistochemistry, and immunocytochemistry. Please note that it is recommended to use Strep-MAB-Immo or Strep-Tactin®XT to capture Strep-tag®II or Twin-Strep-tag® fusion proteins from solid phases since the binding affinity is in the pM range.