Due to transportation and handling small amounts of the liquid components of the Cow Prothrombin ELISA Kit can get caught on the walls or lid of the vial. Prior to use be sure to briefly centrifuge all vials to ensure that all of the content is on the bottom. Do not freeze the kit, as this might denaturate the standards and the peptide chains of the antibodies used for the production if the ELISA kit. Substrate A and Substrate B are light sensitive, therefore you should protect the kits from direct light. When using the vials of Substrates A and B you may cover them in aluminium foil to protect them from light influences.