Preliminary study of mechanism of non-invasive blood glucose measurement based on near-infrared diffuse reflectance spectroscopy

Abstract

Non-invasive glucose measurement by near-infrared spectroscopy is mainly based on the absorption of glucose. However, for non-invasive blood glucose measurement, the diffuse reflectance spectra are influenced not only by the absorption coefficient, but also by the scattering coefficient, anisotropy factor, and refractive index, which are normally nonlinear with the glucose concentrations. Further more, the variations of spectra depend on the relative changing direction of the absorption coefficient and scattering coefficient. In this paper, using the simulated samples of human tissues with different glucose concentrations in different conditions, we discussed the rules of how the glucose concentrations affected the absorption coefficient and scattering coefficient, respectively. The relations between the diffuse reflectance spectra and the absorption coefficient, as well as and the scattering coefficient were also investigated. Thus, we confirmed which of the optical parameters and measurement conditions would affect the diffuse reflectance spectra significantly. Based on the above results, proper methods could be selected to measure blood glucose concentration non-invasively according to different conditions, then the information of glucose absorption would be extracted more effectively, and higher measurement precision would be expected.

Measurements of optical parameters of phantom solution and bulk animal tissues in vitro at 650nm

“…Many of them use light in the visible and near infrared wavelength range. Up to now experimental methods to determine m a and m 0 s of tissues mostly are based on measurements of the diffuse reflectance or transmittance such as integrating sphere measurement [4,5], sized-fiber reflectometry [6], video reflectometer [7] and oblique-incidence optical fiber reflectometry [8,9]. In general, m a and m 0 s are obtained by means of inverse algorithm e.g.…”

Artificial semi-rigid tissue sensitized with natural pigments: Effect of photon radiations

“…Up to now experimental methods to determine absorption coefficient, μ a , and scattering coefficient, μ s , of tissues are mostly based on measuring the reflectance or/and transmittance via integrating sphere. [ 20 21 ] Knowing optical parameters of biological tissue, including absorption coefficient ( μ a ), scattering coefficient ( μ s ) are essential for effective and safe applications in medical therapeutics. [ 22 23 ] The absorption and scattering of photons in biological tissues are characterized by the absorption coefficient and scattering coefficient; these coefficients represent the attenuation of incident radiation intensity due to absorption and scattering per unit length in a tissue.…”