School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China.
Anal Bioanal Chem. 2022 Mar;414(7):2471-2480. doi: 10.1007/s00216-022-03888-w. Epub 2022 Feb 15.
A new dual-mode ratiometric fluorescence and colorimetric probe for selective determination of Cu was developed based on blue-emission sulfur quantum dots (SQDs) and yellow-emission carbon quantum dots (CQDs). The fluorescence and absorbance of CQDs increased in the presence of Cu due to the Cu -oxidized o-phenylenediamine group on the surface of the CQDs. Because of the inner filter effect between SQDs and CQDs-Cu, the fluorescence response of SQDs decreased following the introduction of Cu. Furthermore, in the presence of Cu, the dual-mode SQD-CQD probe showed visible color changes under both ultraviolet light and sunlight. Under optimal conditions, the dual-mode probe was used to quantitatively detect Cu with a linear range of 0.1-5.0 μM for ratiometric fluorescence and colorimetry, with a limit of detection of about 31 nM and 47 nM, respectively. Finally, the dual-mode probe was used for the determination of Cu in practical samples to expand the practical application, and the difference between ratiometric fluorescence and colorimetric methods was compared. The recovery results confirmed the high accuracy of the dual-mode probe, showing that it has immense potential for sensitive and selective detection of Cu in practical samples.
一种基于蓝色发射的硫量子点（SQDs）和黄色发射的碳量子点（CQDs）的新型比率荧光和比色双模式探针被开发出来，用于选择性测定 Cu。由于 CQDs 表面的 Cu-氧化邻苯二胺基团的存在，CQDs 的荧光和吸光度在 Cu 的存在下增加。由于 SQDs 和 CQDs-Cu 之间的内滤效应，在引入 Cu 后 SQDs 的荧光响应降低。此外，在 Cu 的存在下，双模式 SQD-CQD 探针在紫外光和阳光下均显示出可见的颜色变化。在最佳条件下，双模式探针用于比率荧光和比色法定量检测 Cu，线性范围分别为 0.1-5.0 μM，检测限分别约为 31 nM 和 47 nM。最后，该双模式探针用于实际样品中 Cu 的测定，以扩展实际应用，并比较了比率荧光和比色法之间的差异。回收结果证实了双模式探针的高准确性，表明其在实际样品中对 Cu 的灵敏和选择性检测具有巨大潜力。
