导读：详细了解蛋白质动力学过程是在分子水平理解相关生物过程的必要条件，至今，已经可以通过给蛋白标记荧光物质实现此目的。但是，这种方法会改变目标蛋白从而影响所观察的生物过程。
如今，德国美因茨大学的研究人员发明了一种新的方法来观测单个蛋白分子。“我们的方法不需标记蛋白就可进行实时追踪。”该研究的领导者Carsten Sönnichsen说。这项研究发表在近日的《纳米快报》上。
该方法利用可以发光的纳米天线，当它们检测到未标记的蛋白时，频率就会发生细微改变，也就是颜色会发生细微变化；这种颜色的改变能够被进一步检测到。如此，就能精准地观测到蛋白分子的动力学过程。
该方法也开启了全新的视觉，使得实时追踪蛋白数量密度的波动、蛋白吸附过程成为可能。该方法除应用在化学领域外，还可以用在生物和医学领域。
Single Unlabeled Protein Detection on Individual Plasmonic Nanoparticles
Irene Ament,Janak Prasad,Andreas Henkel,Sebastian Schmachtel,Carsten S?nnichsen,
The ultimate detection limit in analytic chemistry and biology is the single molecule. Commonly, fluorescent dye labels or enzymatic amplification are employed. This requires additional labeling of the analyte, which modifies the species under investigation and therefore influences biological processes. Here, we utilize single gold nanoparticles to detect single unlabeled proteins with extremely high temporal resolution. This allows for monitoring the dynamic evolution of a single protein binding event on a millisecond time scale. The technique even resolves equilibrium coverage fluctuations, opening a window into Brownian dynamics of unlabeled macromolecules. Therefore, our method enables the study of protein folding dynamics, protein adsorption processes, and kinetics as well as nonequilibrium soft matter dynamics on the single molecule level.
文献链接：https://pubs.acs.org/doi/abs/10.1021/nl204496g
