Cytochrome c‐Capped Fluorescent Gold Nanoclusters: Imaging of Live Cells and Delivery of Cytochrome c

Cytochrome c‐capped fluorescent gold nanoclusters (Au‐NCs) are used for imaging of live lung and breast cells. Delivery of cytochrome c inside the cells is confirmed by covalently attaching a fluorophore (Alexa Fluor 594) to cytochrome c‐capped Au‐NCs and observing fluorescence from Alexa 594 inside the cell. Mass spectrometry studies suggest that in bulk water, addition of glutathione (GSH) to cytochrome c‐capped Au‐NCs results in the formation of glutathione‐capped Au‐NCs and free apo‐cytochrome c. Thus glutathione displaces cytochrome c as a capping agent. Using confocal microscopy, the emission spectra and decay of Au‐NCs are measured in live cells. From the position of the emission maximum it is shown that the Au‐NCs exist as Au₈ in bulk water and as Au₁₃ inside the cells. Fluorescence resonance energy transfer from cytochrome c–Au‐NC (donor) to Mitotracker Orange (acceptor) indicates that the Au‐NCs localise in the mitochondria of live cells.     

有机小分子荧光探针对甲醛的识别及其应用

甲醛不仅用作工业化学品,也是调节人体生理活动的必要代谢产物。但是,人体从外环境过量的摄入甲醛或者内环境甲醛代谢的不平衡,会造成器官癌变和老年痴呆等重大疾病。有机小分子荧光探针以其高灵敏度、高选择性、可视化和原位检测等特点,使其在生物体内外甲醛检测和生物成像领域具有应用优势,同时也为实际产品中甲醛的痕量检测提供一种新方法。近五年来,甲醛荧光探针得到了快速的发展。本文主要从甲醛荧光探针的反应类型、生物体中甲醛的荧光成像以及在实际样品(商品)检测应用三个方面,介绍有机小分子荧光探针对甲醛的识别和应用。最后总结指出,不同类型的有机小分子荧光探针在不断开发、结构优化和光学性能提升及满足辅助生物医学方向长期性研究的同时,也能拓展应用范围,达到短期内对实际产品中甲醛快速(原位)检测的目的。     

基于激光剥蚀-电感耦合等离子体质谱技术的生物元素成像分析

生物体内的微量元素具有十分重要的生物功能,也与许多疾病密切相关。现代生物医学的研究亟需能在组织、细胞等不同水平上原位分析生物样品中微量元素的分析方法。本研究建立了激光剥蚀-电感耦合等离子体质谱( LA-ICP-MS)原位分析生物样品的方法。采用线扫描模式和较小的激光输出能量(﹤1 J/cm2),得到了鼠脑切片和金纳米颗粒暴露后单细胞的金属元素成像图。 LA-ICP-MS具有空间分辨率高、检出限好、运行成本较低等优势,有望在生物医学研究中得到更广泛的应用,发挥更重要的作用。     

金属配位化合物在生物分析、成像以及染色方面的应用

由于优越的光物理和光化学特性,很多金属配合物长期以来被用于生物传感器、生物探针和医学诊断等领域。本文综述了近年来已经或有望成功应用于生命科学基础研究和临床医学诊断众多领域中的多种金属配位化合物,包括几种在成功商业化的体外诊断系统中作为分子探针、生物标记物或蛋白染色剂而广泛应用的金属钌配位化合物和稀土金属配位化合物,在核磁共振成像技术中作为造影剂或影像增强剂的系列金属钆配位化合物,以及在细胞成像、生物标记和蛋白质分析应用中极具商业化应用前景的一些新型环金属铱配位化合物等。此外,本文还对金属配合物结合纳米结构及技术在生物医学领域中的应用作了简单介绍和展望。     

NIR-II fluorescent nanophosphors for bio-imaging

The design of nanoprobes in the second window near-infrared region has grasped a substantial amount of attention due to the flexible emission in the second near-infrared region (NIR-II) region (1,000–1,700 nm). In addition, this region provides the advantage of reduced photon scattering with less autofluorescence for improvement during in vivo fluorescence imaging. NIR-II nanoprobes such as quantum dots, AIEgens, carbon nanotubes, and polymers are in a constant state of evolution for improved NIR-II emission. Among these probes, lanthanides are explored the most for NIR-II imaging applications. Moreover, nanophosphors, although in their nascent form, are interesting compounds due to their good luminescence properties with efficient energy transfer processes. Our review aims to give insight into nanophosphors, mainly for biological imaging applications. We will also provide a comparative study of lanthanides and nanophosphors for understanding the mechanism and importance of nanophosphors in the future bio-imaging field.