L28/4

Although many cell products are maintained at 4°C for years without loss of activity, shelf-life at 4°C is highly variable. For immediate use, short term storage at 4°C up to two weeks is recommended. For long term storage, divide the solution into volumes of no less than 20 ul for freezing at -20°C or -80°C. The small volume aliquot should provide sufficient reagent for short term use. Freeze-thaw cycles should be avoided. For concentrate or bioreactor products, an equal volume of glycerol, a cryoprotectant, may be added prior to freezing.

Although the optimal Ig concentration for an application varies for each product and must be optimized for each laboratory, a good starting concentration for immunohistochemistry (IHC), immunofluorescence (IF), and immunocytochemistry (ICC) is 2-5 ug/ml. For western blots, the recommended concentration range is 0.2-0.5 ug/ml.