Medical studies have shown dramatic improvements in the clinical outcome of hospitalized Intensive Care Unit patients from tight therapeutic control of blood glucose to normal range. Current protocols for glucose monitoring require multiple finger-sticks that are labor intensive, prone to inaccuracies and inadequate for appropriate adjustment of the treatment regimen. The glucose sensors that now offer continuous measurement capability through subcutaneous implants measure the glucose concentration not in whole blood but in interstitial fluid. The latter suffers from an inherent time lag with respect to glucose in blood, limiting its clinical utility. Consequently there is an unmet need for an automated blood glucose monitoring system in critical care settings for achieving tight glycemic control.