A Novel Glucose Sensor Based on a Deflecting Membrane MEMS Device

91 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2008.Self-monitoring of blood glucose has become an important and critical tool for effective management of patients with diabetes. This thesis describes a novel MEMS (Microelectromechanical systems) sensor that can continuously measure, in real time, the concentration of glucose in a solution. The device utilizes a glucose-sensitive hydrogel membrane, which swells reversibly in the presence of a glucose containing solution. The amount of swelling is related to the concentration of glucose.A thin hydrogel layer is processed into a laminated membrane architecture that includes one half of a parallel plate capacitor. The resultant swelling of the hydrogel deflects the membrane and moves that capacitor plate. Signal transduction arises directly from motion of the plate with respect to a fixed conducting pad, resulting in a change in capacitance. Hence the presence or variation in the concentration of glucose can be observed as a change in capacitance of the device.In order to develop the continuous monitoring glucose sensor, various performance aspects, like the optimal hydrogel recipe and crosslink density as well as the repeatability of the hydrogel swelling response and the development of an efficient microfabrication scheme to manufacture the sensor, have been researched extensively. This report describes our efforts in analyzing and optimizing these performance aspects to develop the continuous glucose monitoring device.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD