AbstractThe authors describe strongly red-emitting carbon dots (CDs) which were obtained via microwave synthesis using phenylenediamine as the carbon source. The structural and optical properties of the resultant CDs are studied in some detail. The CDs possess (a) longwave emission (peaking at 620 nm under 470 nm excitation), (b) a quantum yield of ~15%, (c) a size of typically 3.8 nm; and (d) good photostability. The CDs have a pH-dependet response that covers the pH 5 to 10 range, and their fluorescence is quenched by ferric ions. The CDs can detect ferric ions in aqueous samples in the 0 to 30 μM concentration range with a lower detection limit of 15 nM. The CDs were also used to image pH values and ferric ions in E. coli bacteria. Graphical abstractThe red-emitting carbon dots with high stability are synthesized which show dual response to pH-values and ferric ions in aqueous solution and biological media simultaneously.

中文翻译：

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发红光且高度稳定的碳点，对 pH 值和三价铁离子具有双重响应

摘要 作者描述了以苯二胺为碳源通过微波合成获得的强发红光碳点 (CDs)。对所得 CD 的结构和光学特性进行了一些详细研究。CD 具有 (a) 长波发射（在 470 nm 激发下在 620 nm 处达到峰值），（b）~15% 的量子产率，（c）尺寸通常为 3.8 nm；(d) 良好的光稳定性。CD 具有 pH 依赖性响应，涵盖 pH 5 到 10 范围，并且它们的荧光被三价铁离子淬灭。CD 可以检测 0 到 30 μM 浓度范围内的水性样品中的铁离子，检测下限为 15 nM。CD 还用于对大肠杆菌中的 pH 值和三价铁离子进行成像。