EAGER: Single Quantum Dots via 2-Photon Excitation

EAGER：通过 2 光子激发的单量子点

• 批准号: 0968976
• 负责人: Paul Selvin
• 金额: $ 23.36万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-01 至 2013-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0968976&HistoricalAwards=false
• 关键词: EAGER; Single; Quantum; Dots; via

Lay Abstract0968976EAGER: Single Quantum Dots via 2-Photon ExcitationSelvin, Paul R. Intellectual merit. A two-photon fluorescence microscope will be used to excite individual quantum dots (q-dots), attached to in vitro and in vivo biological specimens. Eventually, the aim is to demonstrate super-accuracy and super-resolution, i.e. accuracy and resolution beyond the diffraction limit of the microscope ( 10 nm) using the methods that will be developed. Two-photon excitation has been shown to be incredibly useful as a means to obtain simultaneous resolution in x, y, and z directions (using the technique known as confocal microscopy), to minimize the effect of light scattering, and to excite multiple fluorophores simultaneously with a single excitation wavelength of light. One-photon excitation of q-dots has already been extremely useful as a means to achieve very bright q-dot emission, long photostability, and the accuracy to visualize individual q-dots at the single-molecule level. In this project, preliminary results indicate that individual q-dots can also be easily visualized with two-photon microscopy under enhanced conditions that rely on extremely low light intensities to excite the q-dots. A goal of this project is to optimize these conditions for 2-photon excitation under biological conditions in order, for instance, to watch molecular motors move (e.g., kinesin and myosin), or to catch a phage virus in the act of infecting a bacterium. The PI has obtained promising preliminary results with wide-field excitation (i.e., not focusing the light down to a diffraction-limited spot) but without a confocal effect needed for z-resolution. To obtain z-resolution, the researchers will repeat the usual methodology but will enhance it in two important ways. First, a highly sensitive charge-coupled detector (CCD) camera will be used to increase the speed of image acquisition. Second, a spatial light modulator will be used to hit the sample with a 10 × 10 array of near-diffraction limited spots, further increasing speed and also permitting super-accuracy and super-resolution in all three spatial dimensions. Broader impacts. The broader goals of the project are to enable new biological discovery through the development and biological application of two-photon excitation of individual q-dots. Many of the techniques are (or potentially will become) extremely simple. Therefore, it is anticipated that the project will result in generalized techniques that will be widely available to many laboratories interested in visualizing single molecules in living cells and other biological specimens. The project will also enhance the training and expertise of the undergraduates and graduate students who will be involved in the project.

通过双光子激发的单量子点。智力上的优点。 双光子荧光显微镜将用于激发附着在体外和体内生物样本上的单个量子点（q点）。最终，目标是证明超精度和超分辨率，即使用将开发的方法超过显微镜衍射极限（10 nm）的精度和分辨率。 双光子激发已被证明是非常有用的，作为一种手段，以获得在x，y和z方向的同时分辨率（使用技术称为共焦显微镜），以尽量减少光散射的影响，并激发多个荧光团同时与一个单一的激发波长的光。 单光子激发的q点已经非常有用，作为一种手段，以实现非常明亮的q点发射，长期的光稳定性，并在单分子水平上可视化单个q点的准确性。 在这个项目中，初步结果表明，在依赖于极低光强来激发q点的增强条件下，单个q点也可以很容易地用双光子显微镜可视化。该项目的一个目标是优化这些条件，以便在生物条件下进行双光子激发，例如，观察分子马达的移动（例如，驱动蛋白和肌球蛋白），或者在感染细菌的过程中捕获噬菌体病毒。 PI已经用宽场激励获得了有希望的初步结果（即，不将光向下聚焦到衍射限制点），但没有z分辨率所需的共焦效应。为了获得z分辨率，研究人员将重复通常的方法，但将以两种重要的方式增强它。首先，将使用高灵敏度的电荷耦合检测器（CCD）照相机来提高图像采集速度。 其次，空间光调制器将用于用10 × 10阵列的近衍射极限光斑撞击样品，进一步提高速度，并在所有三个空间维度上实现超精度和超分辨率。更广泛的影响。 该项目更广泛的目标是通过开发和生物学应用单个q点的双光子激发来实现新的生物学发现。许多技术是（或可能会变得）非常简单。 因此，预计该项目将导致通用技术，将广泛提供给有兴趣在活细胞和其他生物标本中可视化单分子的许多实验室。该项目还将加强对将参与该项目的本科生和研究生的培训和专门知识。