漫反射光谱技术快速无创检测皮肤胆固醇

针对皮肤胆固醇无创检测的迫切需求，设计了一种基于微型光谱仪的便携式和智能化的皮肤漫反射光谱实时测量系统。配制毛地黄皂苷—辣根过氧化物酶共聚物溶液，利用毛地黄皂苷可与皮肤胆固醇分子中的羟基特异性结合和辣根过氧化物酶能与TMB试剂(主要成分为3,3’,5,5’-四甲基联苯胺)反应显色的特性，实现皮肤胆固醇的高灵敏和高特异的识别与指示，并通过测量反应后颜色的变化程度来定量皮肤胆固醇的浓度。以与人体皮肤结构相近的猪皮肤为实验对象，采用萃取法获得梯度浓度的胆固醇样本，利用上述光谱测量系统检测样本内的胆固醇浓度来验证该方法的可行性。实验结果显示，相对漫反射率能够区分不同浓度的胆固醇样本，在特征单波长(442，450和463 nm)处和特征波段442~500 nm内，漫反射率强度因子均可以定量反映样本内的胆固醇浓度，经线性拟合，判定系数R2分别为0.960，0.959，0.958和0.958。研究结果表明，使用漫反射光谱技术可以实现皮肤胆固醇的快速无创检测，将其应用于动脉粥样硬化性疾病风险评估，对于该类疾病的防控具有重要意义。

Rapid and Noninvasive Detection of Skin Cholesterol with Diffuse Reflectance Spectroscopy Technology

Due to the urgent need for noninvasive detection of skin cholesterol,a portable,intelligent and real-time skin diffuse reflectance spectroscopy measurement system was designed based on a micro-spectrometer.Digitonin-horseradish peroxidase copolymer solution was prepared.According to the properties digitonin binds to the hydroxy of cholesterol molecular specifically and the horseradish peroxidase reacts with TMB color solution (the main component is 3,3’,5,5’-tetramethylbenzidine )a color change was produced,by which the skin cholesterol was identified and instructed with high sensitivity and high specificity,and the concentration of skin cholesterol was quantified by measuring the degree of color change.In order to validate the feasibility of this method,pig skin which is similar to human skin was taken as the experimental subj ect,and cholesterol samples of gradient concentration were achieved through the extraction.After that the spectroscopy measurement system was adopted to detect the cholesterol concentration.The experiment result showed that,relative diffuse reflectance can distinguish the cholesterol samples with different concentrations,and the diffuse reflectance intensity factor can quantity the concentrations of cholesterol at charac-teristic wavelengths (442,450 and 463 nm)and characteristic wavelength band of 442~500 nm.Linear fitting curves were ob-tained with the determination coefficient R2 were 0.960,0.959,0.958 and 0.958,respectively.The study has shown that, using diffuse reflectance spectroscopy technology can realize noninvasive rapid detection of skin cholesterol,and applying it to the risk assessment of atherosclerotic diseases would contribute to the prevention and control of such diseases significantly.