Study on the noninvasive blood glucose measurement by diffusion reflectance NIR spectroscopy

The noninvasive measurement of human blood glucose has been a hotspot for a long time to all clinical workers over the world. In this paper the noninvasive measurement of human blood glucose with diffusion reflectance NIR spectrum method is presented. The thumb fingertip, the palm and the wrist with vein are chosen for the collection of diffusion reflectance NIR spectroscopy from six different age healthy volunteers using Nexus-870 and its NIR fiber port smart accessory. The calibration model is set up in 7500similar to8500cm(-1) region that has the absorption of the glucose using Partial Least Squares (PLS) method with the first and second derivative spectral that had been smoothed and baseline corrected for single volunteer. The actual blood glucose value is determined by an ultraviolet spectrophotometer. The model with the spectrum obtained at the wrist is better than from other part for all volunteers, and it is much steadier with the second derivative pretreatment spectral than with the First derivative ones. The correlative coefficients are all over 0.93772; RMSECs are all less than 0.310 and the max differences are between -0.6mmo/L and +0.8mmo/L with the second derivative method. Some samples are kept for prediction with their own model. The differences are under 0.875529mmol/L.