Employing Cryptococcus-directed carbon dots for differentiating and detecting m-benzenediol and p-benzenediol

Distinguishing the isomers is considered to be challenging, and shows the great importance in the biochemical and pharmaceutical fields. Herein, the blue carbon dots (CDs) were successfully raised on the basis of a facile hydrothermal way, since Cryptococcus served as the carbon source. Importantly, the as-prepared CDs were employed to achieve the differentiation and detection of two benzenediols. To be specific, the fluorescence of CDs was enhanced once m -benzenediol (resorcinol) was added, while introducing p -benzenediol (hydroquinone) lead to their fluorescence quenching. Towards the mechanism, the addition of m -benzenediol promoted the formation of hydrogen bonds between m -benzenediol and CDs, and thus resulting in their enhanced fluorescence. In contrast, the fluorescence quenching occurred due to the electron transferring from the rich-electrons of CDs to p -benzoquinone, when p -benzenediol was oxidized to be p -benzoquinone. Therefore, a differentiating strategy of two isomers has been proposed, and also contributed to detecting m -benzenediol and p -benzenediol concentrations in the ranges of 2 × 10 −3 to 1 × 10 −7 M and 2 × 10 -5 to 2 × 10 -9 M, respectively. Although there already existed the high performance liquid chromatography and other chemical methods for determining benzenediols, the current strategy provided a new way of distinguishing and assaying the isomers of benzenediols.