The National Committee for Clinical Laboratory Standards (NCCLS) provides the following recommendations for storing blood specimens:
– Store samples at 22°C (72° F) for no longer than 8 hours.
–If the assay will not be completed within 8 hours, refrigerate the sample at 2–8 °C (36–46 °F).
–If the assay will not be completed within 48 hours, or for shipment of samples, freeze at or below –20 °C (-4 °F).
•Samples are not to be repeatedly frozen and thawed because this can cause analyte deterioration. Samples are to be thawed only once.