Targeting Tools: Streptavidin-ZAP

Streptavidin-ZAP (Cat. #IT-27)

Saporin conjugated to streptavidin is one of the most useful reagents that we have produced at ATS. It has been used in a wide variety of studies both in academic research and pharmaceutical/biotech labs. Workers are able to easily see if their molecule, that is biotinylated, is internalized by the target cells. The simple read-out of cell death requires only a microscope, but is also easily scaled up for industrial use. The streptavidin-biotin bond is so strong that streptavidin-ZAP can even be used in vivo. The technique can be used with all sorts of molecules: growth factors, peptide ligands, cytokines, antibodies—anything that can be biotinylated. Can’t biotinylate it? Then let us do it for you!

KNRK cells are plated at 2500 cells/well and incubated overnight. Streptavidin-ZAP is premixed with Biotinylated-IB4 in equimolar concentrations. Saporin, IB4-SAP, and the Streptavidin-ZAP + Biotinylated-IB4 mixture are then added in 10-μl volumes and the plates are incubated 72 hours. PMS/MTS developing reagent is added and the plates are incubated 15-30 minutes, then read at 490 nm.