Figure 6

A commercially available subcutaneous glucose sensor. Five views (A, B, C, D and E). (A) A commercially available subcutaneous glucose sensor. (B) Exploded-view of a generic glucose sensor structure. (C) The tip of the glucose sensor with its three layers. (D) The glucose sensor needle placed under the skin in the subcutaneous tissue, where the electrochemical reaction produces a DC current (nano-Amperes) that is directly proportional to the glucose concentration. (E) Response of the Medtronic Minimed subcutaneous sensor (thin line) to a step change in serum glucose (black circles) (re-drawn from data in Ref. [16])