The serum is collected from healthy adult animals heat-treated, centrifuged to remove any precipitated proteins and filter sterilized. All batches of Goat Serum Blocking Solution are tested with the appropriate antibody for possible cross-reactivities. The serum is supplied as native with 0.05% sodium azide. Following dilution, this reagent can be used for blocking non-specific binding in immunohistology and western blotting applications.