High-Speed Dual-Wavelength Optical Polarimetry for Glucose Sensing
Abstract
To non-invasively measure glucose concentrations across the aqueous humor of the eye, a high-speed, dual-wavelength optical polarimetric approach is proposed that addresses a key limitation of prior set-ups – system response time – while compensating for time-varying motion artifact due to corneal birefringence.
This research is made up of three goals. The first goal is to design and construct a high-frequency, ferrite core Faraday rotator that can both rotate and modulate linearly polarized light in a frequency range of 30 to 75 kHz. The second goal is to implement a single ferrite core Faraday rotator into the current polarimetric approach. The third goal is to replace three air-core Faraday rotators with two ferrite core Faraday rotators for both modulation and compensation, allowing for two different signals to be measured on a single photodetector.
In vitro phantom studies are performed with and without motion artifact. The sensor is shown to stabilize in ~2 msec and provide standard errors for glucose concentration of less than 13 mg/dL in the presence of motion. The results indicate that higher frequency modulation can reduce the overall system stabilization time with minimal loss of accuracy in the presence of motion artifact.
Subject
diabetesmotion artifact
optical polarimetry
glucose sensing
dual wavelength
optical biosensors
Citation
Grunden, Daniel (2015). High-Speed Dual-Wavelength Optical Polarimetry for Glucose Sensing. Master's thesis, Texas A & M University. Available electronically from https : / /hdl .handle .net /1969 .1 /155290.