Fluorescent N-functionalized carbon nanodots from carboxymethylcellulose for sensing of high-valence metal ions and cell imaging. Issue 55 (28th October 2021)

• Record Type: Journal Article
• Authors: Liu, Zhenzhen; Li, Runsen; Li, Yan; Zhou, Jingpeng; Gong, Yumei; Shi, Haiqiang; Guo, Yanzhu; Li, Haiming; Wang, Zhiwei; Zhang, Fengshan
• Is Part Of: RSC advances. Volume 11:Issue 55(2021)
• Page Start: 34898
• Page End: 34907
• Publication Date: 2021-10-28
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d1ra04972k
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : N-CDs were synthesized using simple and fast one-pot hydrothermal treatment, and were successfully applied as sensors for the selective detection of environmental high-valence metal ions and cellular imaging. Abstract : A convenient and sensitive reversible-fluorescence sensing platform for accurate monitoring of high-valence metal ions is still very challenging. As a green kind of fluorescent carbon nanomaterials, carbon dots (CDs) have captured considerable attention because of the stable fluorescence property and low cost. Herein, we fabricated a type of nitrogen-functionalized carbon dots (N-CDs) from CMC as a fluorescent reversible sensing platform for detecting various high-valence metal ions. N-CDs with a mean size of 2.3 nm were obtained and possessed 22.9% quantum yields (QY). A label-free fluorescent probe for detection of high-valence metal ions (Fe 3+, Cr 6+, Mn 7+ ) was established via the fluorescence quenching response. Among them, the detection limit (LOD) toward Fe 3+ ions reached 0.8 µM. We have explored the quenching mechanism of N-CDs to explain the valence state-related electron-transfer fluorescence quenching between high-valence metal ions and N-CDs. Moreover, the valence state-related fluorescence quenching phenomenon of N-CDs in aqueous solution could be effectively recovered by introducing a reducing agent (Ti 3+ ). This "turn off-on" fluorescence recovery system of N-CDs could be applied in different applications covering the selective detection of environmental high-valence metal ions and cellular imaging.