College of Chemistry, Beijing Normal University, Beijing 100875, PR China.
Key Laboratory for Cell Proliferation and Regulation Biology, Ministry of Education, Beijing Normal University, Beijing 100875, PR China.
Biosens Bioelectron. 2012 May 15;35(1):313-318. doi: 10.1016/j.bios.2012.03.010. Epub 2012 Mar 16.
Proteins in human serum are increasingly being studied for their roles in a wide variety of biochemical interactions. To improve the sensitivity of the detection of human serum proteins after native polyacrylamide gel electrophoresis (PAGE), we have developed a fluorescence imaging detection technique for the detection. BSA (bovine serum albumin)-stabilized Au nanoclusters (NCs) were applied as fluorescent probes for imaging, and low-temperature plasma (LTP) treatment of the Au NCs was introduced to enhance the fluorescence imaging. Here, a series of optimization experiments (e.g. those to optimize for pH) were conducted for protein detection after 1-DE and 2-DE, and several types of discharge gases (He, O(2), and N(2)) were selected for the LTP treatment. The possible mechanism of interaction between the proteins and the Au NCs was demonstrated by an isothermal titration calorimetry experiment. Using the present method, a sensitivity of 7-14 times higher than that of traditional staining detection methods was observed in the oxygen LTP-treated Au NCs fluorescence images, and some relatively low abundance proteins (identified by the MS/MS technique) were easily detected. In addition, this fluorescence imaging method was applied to distinguish between the serum samples of patients with liver diseases and those of healthy people. Thus, this fluorescence imaging method is suitable for the highly sensitive detection of various serum proteins, and it shows potential capabilities for clinical diagnosis.
人血清中的蛋白质因其在各种生化相互作用中的作用而越来越受到研究。为了提高天然聚丙烯酰胺凝胶电泳（PAGE）后检测人血清蛋白质的灵敏度，我们开发了一种荧光成像检测技术进行检测。BSA（牛血清白蛋白）稳定的 Au 纳米团簇（NCs）被用作荧光探针进行成像，并且引入低温等离子体（LTP）处理来增强荧光成像。在这里，进行了一系列优化实验（例如优化 pH 值的实验），用于在 1-DE 和 2-DE 后进行蛋白质检测，并选择了几种放电气体（He、O(2)和 N(2)）用于 LTP 处理。通过等温滴定量热实验证明了蛋白质与 Au NCs 之间相互作用的可能机制。使用本方法，在氧气 LTP 处理的 Au NCs 荧光图像中观察到比传统染色检测方法高 7-14 倍的灵敏度，并且可以容易地检测到一些相对低丰度的蛋白质（通过 MS/MS 技术鉴定）。此外，该荧光成像方法被应用于区分肝病患者和健康人的血清样本。因此，该荧光成像方法适用于各种血清蛋白质的高灵敏度检测，并且显示出用于临床诊断的潜力。
