CURRENT STATUS OF THE GLUCOSE SENSOR

This study gives an overview of glucose sensing strategies for potenti al use in diabetes therapy. The basis for the most commonly used amper ometric glucosensors is the Clark electrode which measures oxygen tens ion. Coupling this sensor with glucose oxidase led to the first specif ic ''biosensor'' for glucose measurement. This sen sor has been used f or more than 20 years in the in vitro artificial pancreas (''Biostator ''). The development of implantable glucose sensors has been hampered by the disappointing in vivo behavior of these sensors. Alternative gl ucose sensing techniques including noninvasive approaches are still ex perimental, Combining the microdialysis technique for continuous sampl ing of subcutaneous extracellular fluid with an in vitro on-line amper ometric glucose oxidase electrode (the ''Ulmer Zuckeruhr'' or ''sugar watch'' system), permits continuous glucose sensing for 72 hours. Alth ough there are differences and delays between changes in tissue and bl ood glucose concentrations, a complete automated feedback-controlled i nsulin delivery system is possible if fast acting insulin analogs can close the insulin delivery ''feedback loop.''