In Vivo Near-Infrared Noninvasive Glucose Measurement and Detection in Humans

Abstract

In optical noninvasive glucose detection, how to detect the glucose-caused signals from the constant human variations and disturbed probing conditions is always the biggest challenge. Developing effective measurement strategies is essential to realize the detection. A NIR spectroscopy-based strategy is studied to effectively solve the in vivo measurement issues, obtaining clean blood glucose-caused signals. Two solutions composing our strategy are applied to the NIR spectroscopy-based measurement system to acquire clean raw signals in the data collection. Which are: a customized high signal-to-noise ratio multi-ring InGaAs detector is introduced to reduce the influences of human variations; a fixing and aiming method are introduced to reproduce a consistent measurement condition. 17 cases of glucose tolerance test (GTT) on healthy and diabetic volunteers are conducted to validate the strategy. Human experiment results clearly show that the expected blood glucose changes have been detected at 1550 nm. The average correlation coefficient of the 17 cases of GTT between light signal and glucose reference reaches 0.84. The proposed measurement strategy is verified feasible for the glucose detecting in vivo. The strategy provides references to further studies and product developments for the NIR spectroscopy-based glucose measurement, and references to other optical measurements in vivo.

Temperature distribution and near-infrared spectral characteristics of the multi-layered skin tissue

“…The absorption coefficient, scattering coefficient, and refractive index of the skin layers (as shown in Figure 2(a) and 2(b)) were taken from reference 12. Assuming anisotropy factors is 0.9 for all skin layer 13 . Based on the assumptions stated in section 2.…”

Non-Invasive Glucose Sensing Technologies and Products: A Comprehensive Review for Researchers and Clinicians

“…4.1.5. Near-Infrared (NIR) Spectroscopy Considered one of the most effective techniques, NIR Spectroscopy shines light in the range of 750 nm to 2.5 µm onto the skin, such as the fingerprint, and the reflected light is measured [43][44][45][46][47], with accurate in vivo measurements demonstrated at 1550 nm for this particular technique [48]. Glucose molecules can absorb light, resulting in changes in the intensity of the reflected light at specific wavelengths, which are used to estimate the glucose concentration.…”

Development and optimisation of a near-infrared spectroscopic system for glucose quantification in aqueous and intralipid-based samples

“…The strongest NIR absorption band from water in the NIR biological window is the O-H bond stretch at 1400-1450 nm [43], however water absorption is then at a local minimum in the region of the -CH overtone in glucose around 1688 nm, which means that this band offers promising potential for glucose quantification. NIR glucose sensing studies have been reported on glucose solutions [44][45][46], tissue phantoms [47,48] and human subjects [49,50]. Several different NIR optical variations have been reported, including photoplethysmography [51] and the use of lasers as light sources [52,53]; and the choice of optical components for infrared spectroscopy experiments is important.…”