Wu Bin, Shi Xiaofeng, Han Wei, Wang Taishan, Wang Chunru, Jiang Li
CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences (CAS) Beijing 100190 P. R. China
University of Chinese Academy of Sciences Beijing 100049 P. R. China.
RSC Adv. 2018 Sep 12;8(55):31793-31802. doi: 10.1039/c8ra06120c. eCollection 2018 Sep 5.
An "on-off-on" fluorescent phosphorus/nitrogen co-doped carbon dot (PNCD) probe was explored for the determination of Cr(vi) and dopamine resulting from the inner filter effect (IFE). The blue-emitting carbon dots with high quantum yields of 25.47% as well as a narrow size distribution were synthesized by a rapid, convenient route using HPO and ethylenediamine as the precursors without any surface passivation. A wide linear region in the range of 7-70 μM with a detection limit of 0.71 μM was achieved for Cr(vi). Moreover, the proper reductants can weaken the inner filter effect to recover the PNCD fluorescence by converting Cr(vi) into Cr(iii). Therefore, the PNCDs/Cr(vi) hybrid could also be used as an "off-on" fluorescent probe for detecting dopamine (DA) with a detection limit of 0.49 μM. Consequently, the PNCDs could serve as a powerful fluorescent bi-sensor for detection of both Cr(vi) and DA in practical applications.
一种“开-关-开”型荧光磷/氮共掺杂碳点（PNCD）探针被用于基于内滤光效应（IFE）测定六价铬（Cr(vi)）和多巴胺（DA）。通过使用磷酸（HPO）和乙二胺作为前驱体，采用快速简便的方法合成了具有25.47%的高量子产率以及窄尺寸分布的蓝色发光碳点，且无需任何表面钝化处理。对于Cr(vi)，实现了7 - 70 μM范围内的宽线性范围，检测限为0.71 μM。此外，合适的还原剂可以通过将Cr(vi)转化为Cr(iii)来减弱内滤光效应，从而恢复PNCD的荧光。因此，PNCDs/Cr(vi)复合物也可用作“关-开”型荧光探针来检测多巴胺（DA），检测限为0.49 μM。因此，在实际应用中，PNCDs可作为一种强大的荧光双传感器用于检测Cr(vi)和DA。
