單顆螢光奈米鑽石：基本光物理性質及生物應用

Single Fluorescent Nanodiamonds: Basic Photo-physics Properties and Bio-applications

李旭洋(Hsu-Yang Lee)

指導教授 ： 范文祥

國立臺灣大學/理學院/物理研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.01880

摘要

生物標記，即在生物分子上連接一個可用光學方法觀測的生物標籤。因為這門技術在生物及生醫研究上的應用，使其在近年來成為一門重要的研究主題。螢光奈米鑽石，一種新穎、無毒性、光學穩定性佳的材料，是極有希望及備受矚目的生物標籤。在這個研究中，我們用共焦顯微鏡系統研究旋鍍在玻片上，經表面處理過的35奈米單顆螢光奈米鑽石，並和100奈米的螢光奈米鑽石的觀測結果作比較以瞭解其光學性質和大小的相關性。由來自掃瞄影像、時間曲線、光譜及生命期的證據，顯示其著稱的光學穩定性依舊明顯，且不因大小而有差別，但35奈米的螢光奈米鑽石的生命期則明顯較短。量到的光譜和細胞自發螢光的光譜明顯不同，意味著在細胞影像方面研究的應用性。為了證實這一點，我們用穿透式白光及廣視野螢光顯微鏡系統，觀察拍攝過螢光奈米鑽石的HeLa細胞。我們成功地在細胞內看到單顆螢光奈米鑽石，並確認他們的位置是在細胞質而非細胞核。最後我們提出了一些未來的研究方向。

關鍵字

螢光奈米鑽石 ； 單分子 ； 生物標記 ； 生物標籤 ； 共焦顯微術 ； 光物理

並列摘要

Biolabeling, which is related to attaching an optically-visible marker on a biomolecule, has become a big issue in recent years because of its application in biological and biomedical studies. Fluorescent nanodiamond (FND), as a novel, non-toxic, photostable material, is a hopeful and eye-catching candidate among the biomarkers. In this work, we investigate the basic photophysical properties of the surface-functionalized single 35nm FNDs spin-coated on a coverglass with a confocal microscope system, and the size-dependence of these properties through a comparison with 100 nm FNDs. Evidence from the scanning image, intensity timetrace, spectra, and lifetime again show that their illustrious photostability, still prominent, is independent of both size and the surface treatment used in our study while the lifetime is significantly reduced by the smaller size. In light of the obtained spectrum, which is distinctly different from that of cell autofluorescence protein in both absorption and emission, application of the FNDs in cell imaging is suggested. To confirm this, after the uptake of the FNDs, HeLa cells are observed with both bright-field and wide-field epi-fluorescence system. We have succeeded to find single FNDs in cells and identified that they are in cytoplasm instead of the nucleus. Some future works of the FND research are proposed in the end.

並列關鍵字

fluorescent nanodiamonds ； typeIb diamonds ； single molecule ； confocal ； biolabeling ； biomarker ； HeLa cell ； photophysics ； photobleaching ； blinking

參考文獻

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