text: Secondary antibodies can be conjugated to enzymes such as horseradish peroxidase (HRP) or alkaline phosphatase (AP); or fluorescent dyes such as fluorescein isothiocyanate (FITC), rhodamine derivatives, Alexa Fluor dyes; or other molecules to be used in various applications. Secondary antibodies are used in many biochemical assays  including:
  * ELISA, including many HIV tests
  * Western blot
  * Immunostaining
  * Immunohistochemistry
  * Immunocytochemistry