A new hydrophobic oligofluorene (OF) is synthesized via Suzuki cross-coupling reaction. The absorption and fluorescence spectra are measured in chloroform with high molar absorption coefficient (1.08×10^5 mol^-1·L·cm^-1) and fluorescence quantum yield (0.96). OF is dispersed into water to form nanoparticles with average size of 230 nm from dynamic light scattering (DLS) measurement. The nanoparticles in water still possess high molar absorption coefficient and fluorescence quantum yield. The quantitative cytotoxicity of OF nanoparticles to human lung cancer (A549) cells is measured by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method, showing that OF nanoparticles exhibit low cellular toxicity. OF nanoparticles can be utilized for imaging of live A549 cells. Confocal laser scanning microscopy demonstrates that OF nanoparticles are exclusively located in the cytoplasm, especially around the perinuclear region. OF nanoparticles exhibit good overlap staining with lysosome-specific dye (Lyso Tracker Red), which demonstrates that OF nanoparticles could be used for lysosome-specific imaging.%利用Suzuki偶联反应合成了疏水性寡聚芴分子OF, 并对其在氯仿溶液中的紫外吸收和荧光光谱进行了表征, 表明其具有较大的摩尔吸光系数（1.08×10^5 mol^-1·L·cm^-1）和高荧光量子产率（96%）。 OF分子分散到水中可形成纳米粒子, 动态光散射实验表明其粒径大小约为230 nm。 该纳米粒子在水相中仍保持了较大的摩尔吸光系数以及高的荧光量子产率。 我们利用MTT的方法对OF纳米粒子对人肺癌A549细胞的毒性进行了测试, 结果表明其具有低的细胞毒性, 因此可以用于细胞成像。 共聚焦激光扫描显微镜成像结果显示OF纳米粒子主要分布在细胞质中, 特别是在近核区域周围。 与溶酶体染料Lyso Tracker Red共定位结果表明OF纳米粒子主要存在于溶酶体中, 因此可以用于对溶酶体的特异性荧光成像。
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