可视交叉传感阵列对蛋白质及其热变性过程的快速识别

以卟啉及其衍生物和特异性染料为敏感化学元件, 基于交叉响应原理构建了识别蛋白质的可视6×6阵列. 该阵列以颜色差谱图显示其与蛋白质作用呈现的特异性光谱反应, 采用聚类分析、 主成分分析和欧氏距离对图谱进行了分析. 结果表明, 该阵列可以鉴别模式蛋白牛血清白蛋白(BSA)、 牛血红蛋白(BHb)和卵清白蛋白(Ova)及其混合物, 且有望实现定量分析. 此外, 阵列的高敏感性使其不仅能识别天然蛋白质和不同变性程度的蛋白质, 还能对其热变性过程进行可视化实时监控. 该阵列产生的特殊颜色变化与蛋白质的空间构型、 微环境pH值的差异及溶解度有关. 因此, 该方法不仅能实现对蛋白质的快速识别, 为蛋白质热变性机理的研究提供新途径, 而且在临床医学和食品安全等的实时快速检测方面有潜在的应用价值.

Colorimetric Cross-responsive Sensor Array for Protein and Its Heat-induced Denaturation Identification

A novel colorimetric cross-responsive sensor array for protein identification was designed with prophyrin derivatves and dyes as chemical sensing elements. The 6×6 sensor array could react specifically with various proteins in 5 minutes, and it provided a color change profile before and after the reaction as a unique fingerprint for each specific protein. The image for each sample was then subjected to hierarchical cluster analysis(HCA), principal component analysis(PCA) and Euclidean distance calculation. Bovine serum albumin(BSA), Bovine hemoglobin(BHb) and Ovalbumin(Ova) as well as their mixtures, gave distinct patterns. In addition, native proteins and denatured ones could also be discriminated by the sensor array with high sensitivity, thus leading to their unambiguous identification. Furthermore, the sensor array showed a characteristic of temperature-dependence which visualized the whole heat-induced denaturation of protein. The results suggested that the unique pattern of colorimetric change may be due to the differences of protein conformation, local environmental pH and solubility. This is the essence of the protein discrimination. Therefore, the low cost and fast responsive colorimetric sensor array not only provide an excellent sensing platform for discrimination and quantitative analysis of protein samples, but also pave a new way for the mechanism study of heat-induced denaturation of protein and represent a potential application in real-time monitoring in the field of clinical medicine and food quality assurance.