State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, People's Republic of China.
Anal Chem. 2011 Oct 1;83(19):7340-7. doi: 10.1021/ac2012366. Epub 2011 Sep 9.
Herein, we demonstrated a new optical microscopy method to selectively image small-size gold nanoparticles (GNPs) inside noisy living cells through determination of the difference image between the probe beam (illuminated at the resonance wavelength of GNPs, 532 nm) and the reference beam (illuminated at 473 nm). From computer simulation and single-particle imaging experiments, we demonstrated that GNPs with a diameter of 45 nm could be selectively imaged in the GNPs/cell lysates mixture and inside living cells by dual-wavelength difference (DWD) imaging. The diffusion dynamics of nucleic acids functionalized GNPs on cell membranes and the internalization kinetics of these GNPs by living cells were explored with this method. Our real-time tracking experiments showed that statistically 80% of GNPs were under restricted diffusion on the cell membrane. The cell cytoskeleton fence effect, as observed in the single-particle tracking experiments, may be one of the main factors for the restricted diffusion mode.
在这里，我们展示了一种新的光学显微镜方法，通过确定探针光束（在金纳米粒子的共振波长 532nm 处照射）和参考光束（在 473nm 处照射）之间的差分图像，选择性地对噪声活细胞内的小尺寸金纳米粒子（GNPs）进行成像。通过计算机模拟和单粒子成像实验，我们证明了通过双波长差（DWD）成像，可以在 GNPs/细胞裂解物混合物中和活细胞内选择性地对直径为 45nm 的 GNPs 进行成像。我们使用该方法研究了细胞膜上核酸功能化 GNPs 的扩散动力学以及活细胞对这些 GNPs 的内化动力学。我们的实时跟踪实验表明，统计上有 80%的 GNPs 在细胞膜上处于受限扩散状态。在单粒子跟踪实验中观察到的细胞细胞骨架围栏效应可能是受限扩散模式的主要因素之一。
