Direct optical sensing of single unlabelled proteins and super-resolution imaging of their binding sites
Direct optical sensing of single unlabelled proteins and super-resolution imaging of their binding sites
复制标题
DOI：
10.1038/ncomms5495
复制
发表时间：
2014-07-01
影响因子：
16.6
通讯作者：
Sandoghdar, Vahid
中科院分区：
文献类型：
--
作者：
Piliarik, Marek;Sandoghdar, Vahid
在不使用任何标记的情况下检测单个分析物分子将提高当前生物传感器的灵敏度，提高了生物物质的最终颗粒度的数量级。二十多年来，科学家们已经成功地将光学检测的极限推到了使用荧光的单个分子。然而，生物物理学和标记协议的限制使得这种技术对生物传感的吸引力较小。最近，基于振动光谱、光热检测、等离子体激元和微腔的机制已经被探索用于单个生物分子的无荧光检测。在这里，我们表明，散射干涉检测（iSCAT）可以实现这一目标，在一个直接的和无标记的方式。特别是，我们证明了在缓冲溶液中和在其他丰富的蛋白质的存在下检测癌症标志物蛋白质。此外，我们提出了纳米定位精度的蛋白质结合的超分辨率成像。iSCAT仪器的易用性有望为涉及蛋白质和其他小生物分子的相互作用的无标记研究带来突破。
Detection of single analyte molecules without the use of any label would improve the sensitivity of current biosensors by orders of magnitude to the ultimate graininess of biological matter. Over two decades, scientists have succeeded in pushing the limits of optical detection to single molecules using fluorescence. However, restrictions in photophysics and labelling protocols make this technique less attractive for biosensing. Recently, mechanisms based on vibrational spectroscopy, photothermal detection, plasmonics and microcavities have been explored for fluorescence-free detection of single biomolecules. Here, we show that interferometric detection of scattering (iSCAT) can achieve this goal in a direct and label-free fashion. In particular, we demonstrate detection of cancer marker proteins in buffer solution and in the presence of other abundant proteins. Furthermore, we present super-resolution imaging of protein binding with nanometer localization precision. The ease of iSCAT instrumentation promises a breakthrough for label-free studies of interactions involving proteins and other small biomolecules.