Studies on the Rapid Determination of Glucose Level in Blood Using the Enzyme Electrode, the "Glucose Meter"

A glucose analyzer called "Glucose meter" using an H_2O_2 electrode combined with an immobilized glucose oxidase membrane was evaluated. 1) The time course of the reaction was followed by polarography. 2) Repeatability : Using samples containing glucose levels of from 70 to 296mg/dl, the C. V. was 0.91 to 0.31%, and the day-to-day precision for 10 days was C. V. : 1.67% at x^^^- 131mg/dl. 3) Linearity was confirmed within the range of zero to 400mg/dl. 4) The correlation between the glucose level of serum obtained by this meter and that obtained by SMAC (the GOD-POD-MBTH-DMA method) was very satisfactory, i. e. r=0.998, y=1.033x+5.50, n=83, but the level obtained by this meter was 8% higher than that obtained by SMAC. 5) The glucose level of whole blood obtained by this meter showed very satisfactory correlation with that of plasma, i. e. r=0.998, y=0.898x-4.76, n=60, but the level of the former was about 13% lower than that of the latter. 6) No influence of ascorbic acid was observed at the normal level. The glucose level measured at 20mg/dl of bilirubin was about 5% lower. However, no influence was found at up to 10mg/dl of bilirubin. The characteristics of the "Glucose meter" are that it is able to obtain specific results in a short time (40 seconds) by a simple procedure using a small amount (20μl) of any sample of whole blood, plasma or serum. Moreover, this meter is easy to transport due to its small size and light weight. For these reasons, this meter is very efficient for routine tests, especially in the case of analyses of a relatively small number of samples, and also for urgent tests.