Long-term stability of glucose: 96-h study using Terumo Glycaemia tubes

Long transportation times of samples can occur due to centralization of laboratories, and also in, for instance epidemiological multicenter studies with one core laboratory. Unsatisfactory glycolysis inhibition is known to threaten the correct measurements of glucose concentration in patient samples. In former studies Terumo Glycaemia tubes proved to be superior to other anticoagulant systems for time periods of up to 24 h. We investigated long-term stability of glucose concentration in Terumo Glycaemia tubes for up to 96 h at room temperature and imitated transport conditions by continuous sample shaking.

Human venous blood samples were collected from 40 healthy blood donors using Terumo Glycaemia tubes. Immediately after sampling, tubes were mixed according to the manufactures recommendations. To simulate transportation conditions samples were placed on a shaker for the entire study period and maintained at room temperature. Samples were (re)centrifuged at 0, 24, 36, 48, 72 and 96 h prior to measuring glucose concentration. The glucose concentration at 0 h was used as baseline for evaluation of long-term stability.

The recovery of glucose was 100% throughout the study, including the 96-h measurements. Deviations of single glucose measurements were within the imprecision of the measurement procedure.

Terumo Glycaemia tubes can effectively stabilize glucose in whole blood samples kept at room temperature on a shaker during a 96-h time period. Therefore, we consider Terumo Glycaemia tubes as a suitable glucose stabilizing tube for long intervals between sample collection and glucose quantification.