Storage and Stability:Store unopened kit at 4ºC; store at -20ºC once opened. Store unopened standard at 4°C; once reconstituted, store at 4°C for up to 12 hours or at -20°C for up to 48 hours. Store other components at 4°C. Kit is stable for 6 months after receipt. For maximum recovery of product, centrifuge the original vials after thawing and prior to removing the cap.