A colorimetric and fluorometric dual-mode carbon dots probe derived from phenanthroline precursor for the selective detection of Fe
2+ and Fe
3.
ANAL SCI 2023;
39:325-333. [PMID:
36539607 DOI:
10.1007/s44211-022-00236-x]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 12/09/2022] [Indexed: 12/24/2022]
Abstract
Iron's metabolism is heavily involved in the regulation of redox balance for cell functions, however, the simultaneous monitoring of Fe2+/3+ concentration is still a great challenge due to their transitional nature in biological systems. A novel type of carbon dots (CDs) was synthesized by solvothermal treatment with 5-amino-1,10-phenanthroline (Aphen) and salicylic acid as precursors, and the resulting targeted CDs (T-CDs) were used to simultaneously detect Fe2+ and Fe3+. Comprehensive experimental characterizations revealed that the strong binding affinity of Aphen moiety to Fe2+ leads to the formation of rigid T-CDs aggregates, which causes a substantial enhancement of fluorescence intensity, whereas Fe3+ could cause the fluorescence quenching of T-CDs due to the oxidation-reduction induced electron transfer. These different fluorescence responses allow T-CDs to sensitively differentiate Fe2+ from Fe3+, and give the limit of detection (LOD) of 1.78 and 2.78 μM for Fe2+ and Fe3+, respectively. Furthermore, the Aphen dominated structure endows the T-CDs with a colorimetric response to Fe2+ with a LOD of 0.13 μM, which is very different from Fe3+. Thus, the dynamic changes of Fe2+ and Fe3+ in solution can be accurately monitored by T-CDs within the total iron concentration of 50 μM, which is probably the most sensitive dual-mode probe reported so far. In addition, this probe is successfully applied to detect the Fe2+/3+ concentration in cells, demonstrating a huge application potential in the sensing of the dynamic equilibrium of these important transition metals during the cell metabolism or stimulated process. The dynamic changes of Fe2+ and Fe3+ in solution can be accurately monitored by carbon dots based on the colorimetric and fluorometric dual-mode.
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