Tear TOUCH Glucose Sensing

The Need:


Diabetes mellitus (DM) affects over 284 million people in the world, 20 million people in the US alone. Self-monitoring of blood glucose (SMBG) is the primary method of managing diabetes. Many diabetics struggle to comply with physician orders to monitor their blood glucose levels 2-8 times per day due to the current requirement for painful finger prick techniques to obtain blood for testing. Noncompliance results in poorly controlled glucose levels which can lead to amputation, blindness, and even death. Economically, noncompliance has led to an estimated $300 billion burden on the US healthcare system in 2009.
Thus, the goal of our disposable Tear TOUCH Sensor is to reduce pain associated with blood glucose sensing by using tear fluid as the sampling medium.

Progress so far:

  • Design of an integrated capture, transfer, and sensing system
  • Highly sensitive enzymatic assay on a single strip platform
  • Small sample volume
  • Pain-Free sampling method
  • Elimination of sample evaporation
  • Improved glucose assay
    • Devices that are 15.8% reproducible (compared to standard self-monitoring blood glucose requirements of 20% by the FDA)
      Assay allows tear glucose concentrations (~100x lower than blood) to be measured with a LOD currently calculated at 43.4 uM glucose (0.78 mg/dL).

Future Work:

  • Improving sensitivity and selectivity
  • Developing methods of sterilization and storage
  • Developing scaled fabrication setup and improving manufacturability
  • Redesigning fluidics capture to make sensor more user-friendly

Recent Publications

Daniel K. Bishop, Jeffrey T. La Belle, Stephen R. Vossler, Dharmendra R. Patel, and Curtiss B. Cook. A disposable tear glucose biosensor – part 1: design and concept testing. Journal Diabetes Science and Technology. 2:6, 299-306. Jeffrey T. La Belle, Daniel K. Bishop, Stephen R. Vossler, Dharmendra R. Patel, and Curtiss B. Cook. A disposable tear glucose biosensor – part 2: system integration and model validation. Journal Diabetes Science and Technology. 2:6, 307-11.

Related Intellectual Property

See AzTE’s (M09-090L ) Integrated device for surface-contact sampling extraction and electrochemical measurements
For more information regarding this technology contact:

John Schneider, Ph.D.
Assistant Director of Intellectual Assets
Tel: 480.884.1894
Email: jschneider@azte.com