Department of Chemistry, College of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, P. R. China.
J Mater Chem B. 2019 Apr 7;7(13):2169-2176. doi: 10.1039/c8tb03184c. Epub 2019 Feb 27.
The sensitive and selective detection of endogenous glutathione (GSH) is of great significance due to its key role in physiological and pathological processes. Herein, we report a novel on-off-on transferrin (Tf)-coated gold nanocluster (AuNCs@Tf) with low toxicity, good stability and intense red fluorescence which can enter living cells and is mainly located in lysosomes. In addition, the fluorescence of AuNCs@Tf is quenched by Cu, indicating its sensitivity to Cu with a detection limit of 0.23 μM at pH 4.5. Interestingly, we found that the quenched AuNCs@Tf-Cu system only has a special affinity for GSH with a detection limit of 2.86 μM so that invisible AuNCs@Tf-Cu can be gradually illuminated by endogenous GSH in the lysosomal environment of tumor cells with increase in time. More excitingly, the AuNCs@Tf-Cu system can illuminate tumor cells rather than normal cells, resulting in its successful application in cancer cell recognition, which implies its great potential application in cancer diagnosis. Moreover, the AuNCs@Tf was also applied in Cu strips and encryption/decryption of information.
由于内源性谷胱甘肽 (GSH) 在生理和病理过程中的关键作用，因此对其进行敏感和选择性检测具有重要意义。在此，我们报道了一种新型的具有低毒性、良好稳定性和强红色荧光的开关型转铁蛋白（Tf）包覆的金纳米簇（AuNCs@Tf），其可以进入活细胞，主要定位于溶酶体。此外，AuNCs@Tf 的荧光被 Cu 猝灭，表明其对 Cu 具有灵敏度，在 pH 4.5 时检测限为 0.23 μM。有趣的是，我们发现猝灭的 AuNCs@Tf-Cu 体系仅对 GSH 具有特殊亲和力，检测限为 2.86 μM，因此在时间的推移下，内源性 GSH 可以逐渐使不可见的 AuNCs@Tf-Cu 在肿瘤细胞的溶酶体环境中被照亮。更令人兴奋的是，AuNCs@Tf-Cu 体系可以照亮肿瘤细胞而不是正常细胞，从而成功地应用于癌细胞识别，这意味着其在癌症诊断中有很大的潜在应用。此外，AuNCs@Tf 还应用于 Cu 带和信息的加密/解密。
