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Multiple Choice

Shelf life of evacuated tube is defined by which factors?

Shelf life of evacuated tubes is defined by the stability of the additive and the integrity of the vacuum. The additive (such as EDTA, citrate, heparin, or a clot activator) must stay chemically and functionally stable for the duration of the stated shelf life, so it continues to preserve or anticoagulate the sample as intended. If the additive degrades, the blood may clot or the chemistry may be altered, compromising test results. At the same time, the vacuum in the tube must be retained; a loss of vacuum can allow air ingress or improper blood-to-additive ratios, leading to inconsistent fill volumes, dilution effects, or premature clotting. Both factors together determine how long the tube can reliably be used while delivering accurate and reproducible results.

Shelf life of evacuated tubes is defined by the stability of the additive and the integrity of the vacuum. The additive (such as EDTA, citrate, heparin, or a clot activator) must stay chemically and functionally stable for the duration of the stated shelf life, so it continues to preserve or anticoagulate the sample as intended. If the additive degrades, the blood may clot or the chemistry may be altered, compromising test results. At the same time, the vacuum in the tube must be retained; a loss of vacuum can allow air ingress or improper blood-to-additive ratios, leading to inconsistent fill volumes, dilution effects, or premature clotting. Both factors together determine how long the tube can reliably be used while delivering accurate and reproducible results.