Fluorescent Carbon Dots for Sensitive and Rapid Monitoring of Intracellular Ferrous Ion

Abstract

Although iron is an essential constituent for almost all living organisms, iron dyshomeostasis at a cellular level may trigger oxidative stress and neuronal damage. Hence, there are numerous reported carbon dots (CDs) that have been synthesized and applied to determine intracellular iron ions. However, among reported CDs focused to detect Fe3+ ions, only a few CDs have been designed to specifically determine Fe2+ ions over Fe3+ ions for monitoring of intracellular Fe2+ ions. We have developed the nitrogen-doped CDs (NCDs) for fluorescence turn-off detection of Fe2+ at cellular level. The as-synthesized NCDs exhibit a strong blue fluorescence and low cytotoxicity, acting as fluorescence probes to detect Fe2+ as low as 0.702 µM in aqueous solution within 2 min and visualize intracellular Fe2+ in the concentration range from 0 to 500 µM within 20 min. The as-prepared NCDs possess some advantages such as high biocompatibility, strong fluorescence properties, selectivity, and rapidity for intracellular Fe2+ monitoring, making NCDs an excellent nanoprobe for biosensing of intracellular ferrous ions.

Solid-Phase Synthesis of Red Fluorescent Carbon Dots for the Dual-Mode Detection of Hexavalent Chromium and Cell Imaging

“…Carbon dots (CDs), as one of the most dynamic research objects in optical materials, not only inherit the excellent optical properties of traditional semiconductor quantum dots, but also make up for the shortcomings of traditional fluorescent materials in cytotoxicity, environmental, and biological risks [ 18 ]. CDs exhibit a broad prospect in environmental and biological analysis applications due their inherent attributes of good water solubility, stable chemical properties, and surface tunability [ 19 , 20 , 21 ]. Specially, red fluorescence CDs (R-CDs) possess unique advantages for bioimaging and biosensing application, which can effectively eliminate the interference of background fluorescence from biological tissue [ 22 ].…”