Integrative, Hybrid and Complex Systems Qiao Lin, Department of Mechanical Engineering, Columbia University Qian Wang, University of South Carolina A Miniature Implantable Device for Continuous Glucose Monitoring
Intellectual Merit:
This project investigates a miniature, subcutaneously implantable sensor system with the potential to allow long-term continuous monitoring of glucose in interstitial fluid. Enabled by micro electro-mechanical systems (MEMS) technology, the device will exploit viscometric measurements of non-consumptive, reversible equilibrium binding (i.e., affinity binding) of glucose to a glucose-specific polymer. The device consists of a vibrating element sealed in a micro-chamber by a semipermeable membrane. A solution of a polysaccharide, crosslinked by the glucose-specific polymer, fills the micro-chamber. Glucose permeates from subcutaneous tissue into the chamber through the membrane and competitively binds to the polymer, causing reversible de-crosslinking of the polysaccharide. The resulting changes in solution viscosity are obtained via vibration measurements, thereby determining the glucose concentration. Measurement data transmission can be achieved by wireless circuitry.
Broader Impact:
Currently, approximately 20.8 million people in the United States have diabetes. It has been demonstrated that close monitoring of daily blood glucose levels reduces the risk of diabetes-related complications. This can be accomplished by continuous glucose monitoring (CGM), which is the intended use of the miniature affinity sensor to be developed in this research. Compared with other CGM approaches, the device under investigation utilizes equilibrium binding and does not involve consumption of glucose. This implies that, when implanted, the device can be more tolerant to retardation of glucose transport resulting from fouling by biological agents. This allows stable, long-term continuous glucose monitoring. With the affinity sensing principle extendable to other chemical substances of analytical interest, the device is useful for the care of diabetes and potentially other diseases, as well as applications such as metabolic monitoring in the battlefield, bioterrorism threat detection, and environmental toxin monitoring. The research is integrated with graduate and undergraduate education and involves active educational outreach activities in the New York, NY and Columbia, SC, areas.
