Upon receipt, the kit should be stored at -20 °C. Please use within 6 months from the date of shipment. After initial use, Wash Buffer Concentrate, Assay Diluent, TMB One-Step Substrate Reagent, HRP-Streptavidin, Stop Solution and Cell Lysate Buffer should be stored at 4 °C to avoid repeated freeze-thaw cycles. Return unused wells to the pouch containing desiccant pack, reseal along entire edge and store at -20 °C. Reconstituted Positive Control should be stored at -70 °C.