应用中红外光谱法对手指、血液以及干燥后的血液进行了测定,并同时与血糖仪测定的血糖作对比研究。研究结果表明,对红外光谱图进行分析时,选择1455cm^-1附近的谱峰作为基准峰,可使1120cm^-1附近的谱带得到准确度较高的相对强度。干燥后的血液与手指的光谱图大致相似并且与实测的血糖值的投点图具有相近的斜率,说明中红外光谱法检测人体血糖具有较高的可靠性。对同一手指进行不同时间的测定,以1120cm^-1谱带强度来表征血糖的浓度,其随时间的增加而增加,是因为人体内的葡萄糖不仅存在于血液中,而且也存在于皮肤的分泌物中,而分泌物会随时间的增加而增加。根据测定的1120cm^-1谱带的相对强度与实测血糖值所得的线性关系图表明,洗手后10min的准确度要高于4min。
The blood glucose concentrations of volunteers from diabetes patients and healthy adults (all patients and volunteers who joined this experiment gave their consents) were measured by using a modified WQF-200 FTIR spectrometer with a newly designed ATR accessory from the Beijing Rayleigh Analytical Instrument Corp.The determination basis for this technique from the physiological point of view is also discussed based on the experimental results,which indicated that the glucose measured by the FT-Mid-IR-ATR instrument is from the secretions on the skin and glucose components within the body.The secreted glucose components will increase with the time increasing.The authors’ previous study demonstrated 1 120 cm^-1 band as an index to characterize the blood glucose.During the experiments,the authors used the band of 1 455 cm^-1 as internal standard because of its stability,and because the relative intensity of I1 120/I1 455 band possesses the higher sensitivity.Meanwhile,from the spectra,the relative intensity of I1 120/I1 455 band of the glucose in both sources exhibits a linear relationship with blood glucose concentration within the body.The dried blood has the similar spectra as fingers’.The fingers’ spectra will exhibit higher sensitivity if the time of measurement is longer after washing hand,and the results showed that when measured 10 minutes after washing hand,the sensitivity will be higher than that when measured 4 minutes after washing hand.All the results can be used in promoting a convenient,rapid and noninvasive way to monitor the continuous variation of blood glucose concentration of diabetes patients in real time.