| Usually the glucose concentration is measured with enzyme-catalyzed method for the blood from vein or fingertip at present. It not only brings pain but also increases the economy burden for the patients, and it is difficult for the continuous and homely measurement. The most perfect method and technique for noninvasive blood glucose measure has become a hotspot for a long time here and abroad. Significant efforts have been devoted to develop the noninvasive techniques to detect blood glucose concentration by use of various approaches, such as near infrared spectroscopy (NIR), mid-infrared spectroscopy, biosensor and laserraman spectrometry et al, but all the work is in its basic studying stage, and haveing no available instrument comes into being until now. Because NIR can penetrate through skin and body tissue, and there is perfect linearity correlation between the concentration of blood glucose and its NIR absorption, it is much widely used to measure the concentration of blood glucose than other methods mentioned herein before. In this paper, the analysis system is developed with Nexus 870 of Nicolet Company on the base of the NIR theory analysis, and the systemic study is done for the blood glucose measure firstly here. The NIR character of glucose powder and the removing water absorption ways are analyzed. The spectroscopy range, the spectrum data pretreatment and the chemomtrics method are discussed in detail for the glucose solution. 7500～8500cm-1 and 5500～6500cm-1 containing glucose absorption are selected for the whole spectrum analysis region, baseline correction, smoothing and derivation are chosen as the pretreatment ways and Partial Least Squares (PLS) is the method to build calibration model. The models are built for glucose solution, blood plasma, whole blood and the normal human serum and whole blood. The analysis range is extended to 7500～9500cm-1, and the region for the model built and the method for the data pretreated are confirmed again. The noninvasion measure of human blood glucose is implemented by the combination of the invitro measure and the nondestructive determination for the blood glucose with the full spectral analysis according the glucose metabolization. The results show that the noninvasive measure for blood glucose with NIR is feasible, the wrist with vein is the perfect position for the spectrum collecting and the 7500～8500cm-1 is the best analysis area. For the models built with spectrum from wrist, the correlative coefficients are all over 0.93772; Root Mean Square Errors of Calibration are all less than 0.310 and the max differences are between -0.6mmo/L and +0.8mmo/L; The self-prediction differences of some samples are under 0.89544mmol/L. The NIR detecting system suited to both in vitro and noninvasive measure for blood glucose is designed. The glucose solution is measured with this system, and the result is compared with what is done by Nexus 870. The correctness of the glucose measure method is validated. All the work accumulated a great deal of experimental data for the development of the undestructive blood glucose analysis instrument.
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