Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
Analyst. 2018 Oct 22;143(21):5295-5301. doi: 10.1039/c8an01640b.
In this work, a simple and novel ratiometric fluorescence method based on ROX-DNA-functionalized CdZnTeS quantum dots (QDs) was developed for the detection of dopamine (DA) and tyrosinase (TYR). A ratiometric fluorescent probe was constructed by binding phosphorothioate DNA to the metal ions of QDs, which is a modification-free and low-cost method. DA was easily oxidized to DA quinone under the catalysis of TYR by dissolved O2, which effectively quenched the fluorescence of the QDs. Strong linear correlations were achieved for TYR in the range of 10.0-100.0 ng mL-1 and for DA in the range of 10.0-1000.0 nM. The limit of detection was estimated to be as low as 1.05 ng mL-1 for TYR and 1.93 nM for DA. Moreover, various colors were displayed in the course of detection, which could be observed by the naked eye. Therefore, an on-site and sensitive fluorescence method for the visual detection of DA and TYR can be developed. In addition, the findings revealed the potential applicability of the ratiometric fluorescent probe for the detection of DA and TYR in human serum. This ratiometric fluorescence method is not only sensitive and selective but also rapid and convenient for the detection of the analytes without sophisticated instrumentation.
在这项工作中，开发了一种基于 ROX-DNA 功能化 CdZnTeS 量子点 (QDs) 的简单新颖的比率荧光法，用于检测多巴胺 (DA) 和酪氨酸酶 (TYR)。通过将硫代磷酸酯 DNA 结合到 QDs 的金属离子上，构建了比率荧光探针，这是一种无需修饰且成本低廉的方法。DA 在溶解氧的催化下很容易被氧化为 DA 醌，有效地猝灭了 QDs 的荧光。在 10.0-100.0 ng mL-1 范围内对 TYR 以及在 10.0-1000.0 nM 范围内对 DA 实现了强线性相关性。对 TYR 的检测限估计低至 1.05 ng mL-1，对 DA 的检测限低至 1.93 nM。此外，在检测过程中显示出各种颜色，肉眼即可观察到。因此，可以开发一种用于 DA 和 TYR 的现场灵敏荧光检测方法。此外，研究结果表明，比率荧光探针在人血清中检测 DA 和 TYR 方面具有潜在的适用性。该比率荧光法不仅灵敏、选择性好，而且无需复杂仪器即可快速方便地检测分析物。
