Polarimetric glucose sensing in vitro: a high frequency approach
Conference Paper
Overview
Research
Identity
Additional Document Info
Other
View All
Overview
abstract
Optical polarimetry as a method to monitor glucose levels in the aqueous humor has shown promise as a way to noninvasively ascertain blood glucose concentration. A major limiting factor to polarimetric approaches for glucose monitoring in the aqueous humor is time varying birefringence due to motion artifact. Here, we present a modulation approach for real-time polarimetry that is capable of glucose monitoring in vitro at optical modulation frequencies of tens of kHz and includes the DC-compensation in a single device. Such higher frequency modulation has the potential benefit of improving the signal-to-noise ratio of the system in the presence of motion artifacts. In this report we present a near real-time closed-loop single wavelength polarimeter capable of glucose sensing in vitro at an optical modulation frequency of 32 kHz. The single wavelength polarimetric setup and in vitro glucose measurements will be presented demonstrating the sensitivity and accuracy of the system. Our PID control system can reach stability in less than 10 ms which is fast enough to overcome motion artifact due to heart beat and respiration. The the system can predict the glucose concentration with a standard error of less than 18.5 mg/dL and a MARD of less than 6.65% over the physiologic glucose range of 0-600 mg/dL. Our results indicate that this optical modulation approach coupled with dual-wavelength polarimetry has the potential to improve the of the dual-wavelength approach for in vivo glucose detection applications. 2013 Copyright SPIE.
name of conference
Optical Diagnostics and Sensing XIII: Toward Point-of-Care Diagnostics