Abstract:
Single molecule fluorescence localization microscopy provides molecular localization with a precision in the tens of nanometer range in the plane perpendicular to the light propagation. This opens the possibility to count molecules and correlate their locations, starting from a map of the actual positions in a single molecule super resolution image. Considering molecular pair correlation as an indication of interaction, and a way to discern them from free molecules, we describe a method to calculate thermodynamic equilibrium constants. In this work, we use as a test system two complementary homo-oligonucleotides, one strand marked with Cyanine 3.5 and the other with Alexa Fluor 647. Hybridization is controlled by the amount of each strand, temperature, and the ionic force, and measured in steady state emission. The same samples are examined in Stochastic Optical Reconstruction Microscopy (STORM) experiments with split-field simultaneous two-colour detection. The effect of multiblinking, labelling-detection efficiency, and determination of the critical distance for association are discussed. We consistently determine values in STORM coincident with those of the bulk experiment.
摘要:
单分子荧光定位显微镜在垂直于光传播的平面中以数十纳米范围的精度提供分子定位。这打开了计数分子并关联它们位置的可能性,从单分子超分辨率图像中的实际位置图开始。考虑到分子对相关性作为相互作用的指示,一种将它们与自由分子区分开的方法,我们描述了一种计算热力学平衡常数的方法。在这项工作中,我们使用两个互补的同源寡核苷酸作为测试系统,一条链用花青3.5标记,另一条链用AlexaFluor647标记。杂交由每条链的数量控制,温度,和离子力,并在稳态发射中测量。在具有分裂场同时双色检测的随机光学重建显微镜(STORM)实验中检查相同的样品。多重闪烁的效果,标签检测效率,并讨论了关联临界距离的确定。我们始终确定STORM中的值与批量实验的值一致。