Institute of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung 20224, Taiwan.
J Biomed Nanotechnol. 2009 Oct;5(5):579-85. doi: 10.1166/jbn.2009.1071.
We have demonstrated a time-resolved luminescence (TRL) assay for the sensitive and selective detection of thyroglobulin (Tg), a thyroid cancer marker, in homogeneous solution using water-soluble alpha-D-mannose-conjugated Au nanodots (Man-Au NDs). The Man-Au NDs (1.7 nm in diameter) were prepared from the reaction between Au nanoparticles (2.9 nm in diameter) with 11-mercapto-3,6,9-trioxaundecyl-alpha-D-mannopyranoside (Man-RSH; 0-10 mM). We have found that the luminescence intensity and lifetimes of Man-Au NDs separately become stronger and longer, respectively, upon increasing the concentration of Man-RSH. The Man-Au NDs possess several interesting optical properties, including long luminescence lifetime (> 500 ns) and large Stokes' shift (> 150 nm). The TRL assay is based on the competition between Tg and Man-Au NDs for interacting with concanavalin A (Con A). The fluorescence intensities integrated over the region of 50-400 ns increase upon increasing the concentration of Tg over the range 0.1-2.5 nM. The Con A/Man-Au NDs system in a label-free manner allows the detection of Tg at concentrations as low as 90 pM in the presence of BSA at 50 microM by TRL. With its advantages of rapid and specificity, this present approach holds great potential for diagnosis of cancers.
我们已经展示了一种使用水溶性α-D-甘露糖偶联的 Au 纳米点（Man-Au NDs）在均相溶液中灵敏且选择性地检测甲状腺癌标志物甲状腺球蛋白（Tg）的时间分辨荧光（TRL）测定法。Man-Au NDs（直径 1.7nm）是通过 Au 纳米颗粒（直径 2.9nm）与 11-巯基-3,6,9-三氧杂十一烷基-α-D-甘露吡喃糖苷（Man-RSH；0-10mM）之间的反应制备的。我们发现，随着 Man-RSH 浓度的增加，Man-Au NDs 的荧光强度和寿命分别变得更强和更长。Man-Au NDs 具有几个有趣的光学性质，包括长荧光寿命（>500ns）和大斯托克斯位移（>150nm）。TRL 测定法基于 Tg 与 Man-Au NDs 与伴刀豆球蛋白 A（Con A）相互作用之间的竞争。随着 Tg 浓度在 0.1-2.5nM 范围内的增加，50-400ns 区域的荧光强度积分增加。在 50μM BSA 存在下，Con A/Man-Au NDs 系统以无标记的方式允许在低至 90pM 的 Tg 浓度下进行检测。由于其快速和特异性的优势，这种方法在癌症诊断方面具有很大的潜力。
