In vivo characteristics of needle-type glucose sensor--measurements of subcutaneous glucose concentrations in human volunteers.

To explore the clinical performances of the needle-type glucose sensor, in vivo monitoring was conducted in human subjects. The tissue glucose concentrations measured by glucose sensor were lower than the plasma glucose concentrations by 15%, but a good linear relationship was observed between the tissue and plasma glucose concentrations. The sensing sites between abdomen and forearm did not affect the tissue glucose monitoring. The tissue glucose concentrations after meal intake showed 5 min delayed response to the blood glucose concentrations. After 3 days' continuous monitoring, the "relative" sensor output to the plasma glucose concentration decreased by 26% and the "relative" response time to reach peak value prolonged from 5 min to 13.5 min. These data indicate the clinical usefulness of the needle-type glucose sensor.