Influence Of Other Blood Components On Non-invasive Blood Glucose Sensing Studied With NIR Spectroscopy

Near-infrared spectroscopy for measuring the blood glucose concentration has great prospects and practical significance, but it is very difficult in the practical application, and the measurement accuracy is vulnerable to some factors. One of the main factors is that other blood components have some influence on non-invasive blood glucose sensing with NIR spectroscopy.Based on above reasons, firstly, the methods of biochemical analysis, clinical analysis and spectral analysis are conducted to human blood for describing the relationships between other blood components and blood glucose. Results indicate that the relationships between glucose and other components in the blood of normal people and patients with impaired glucose tolerance are not significant, However, in the blood of people with diabetes, glucose,cholesterol and total protein concentration are negative correlations, even though the relationships with other components is not significant. The near-infrared absorption spectra between blood glucose and other blood components are overlapped, especially the NIR spectra between blood glucose and blood cholesterol are seriously overlapped.Secondly, cholesterol is selected as the object of study, and the influence of cholesterol on non-invasive blood glucose sensing is studied by the method of experimental research. The experimental research includes three steps. First, the NIR absorption spectrum of glucose and cholesterol are obtained and compared with each other. Second, cholesterol is added to glucose solution, and the changes of the NIR absorption spectrum of glucose are obtained. Finally, the spectral data are processed through Partial Least Squares (PLS) modeling, and the prediction models of glucose concentration are build. Results indicate the influence of cholesterol on blood glucose sensing with NIR is considerable, that is, the increment of glucose will increase linearly with the increase of cholesterol concentration, and the quantitative relationship is obtained.Finally, based on above results, a method to correct the influence of cholesterol on blood glucose sensing with NIR spectroscopy is proposed. The method includes three steps. First, the concentration of cholesterol in mixed solution is measured based on the method of reference wavelength. Then, the increment of glucose concentration induced by cholesterol is obtained. Finally, this increment is deducted from the measured glucose concentration. And this correction method is confirmed through experimental research. Results indicate that the prediction accuracy of glucose prediction model will increase to some extent after being corrected. The prediction accuracy can increase by 19.02%~38.36%. It is preliminarily proved that, the correction method proposed in this paper is feasible and effective.