Dual emission carbon dots have a high potential for use as fluorescence-based sensors with higher selectivity and sensitivity. This study demonstrated the possibility of conversion of a biological molecular system with a single emission peak to a double emission carbon dots system. This report is the first to describe the synthesis of dual emission carbon dots by tuning the electronic environment of a conjugated system. Here we prepared carbon dots from a natural extract, from which carotenoids were used as a new source for carbon dots. Formation of the carbon dots was confirmed by images obtained under a transmission electron microscope as well as from a dynamic light scattering study. The prepared carbon dots system was characterized and its optical property was monitored. The study showed that, after irradiation with microwaves, the fluorescence intensity of the whole system changed, without any change in the original peak position of the carotenoid but with the appearance of an additional peak. A Fourier transform infrared study confirmed breaking of the conjugated system. When using ethylene glycol as a surface passivating agent added to these carotenoid carbon dots, the dual emission spectra became more distinct.

中文翻译：

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类胡萝卜素的双重排放碳点：将单一排放转换为双重排放。

双发射碳点具有较高的潜力，可用作具有更高选择性和灵敏度的基于荧光的传感器。这项研究证明了将具有单发射峰的生物分子系统转换为双发射碳点系统的可能性。该报告是第一个描述通过调节共轭体系的电子环境来合成双发射碳点的方法。在这里，我们从天然提取物中制备了碳点，其中的类胡萝卜素被用作碳点的新来源。通过在透射电子显微镜下以及通过动态光散射研究获得的图像证实了碳点的形成。表征所制备的碳点系统并监测其光学性质。研究表明，在用微波辐照后，整个系统的荧光强度发生了变化，但类胡萝卜素的原始峰位置未发生任何变化，但出现了另一个峰。傅立叶变换红外研究证实了共轭体系的破坏。当使用乙二醇作为添加到这些类胡萝卜素碳点中的表面钝化剂时，双发射光谱变得更加明显。