Chitosan-derived N-doped carbon dots for fluorescent determination of nitrite and bacteria imaging

Lili Sun; Hongmei Zhang; Yesheng Wang; Zhong Xiong; Xihui Zhao; Yanzhi Xia

doi:10.1016/j.saa.2021.119468

Chitosan-derived N-doped carbon dots for fluorescent determination of nitrite and bacteria imaging

Spectrochim Acta A Mol Biomol Spectrosc. 2021 Apr 15:251:119468. doi: 10.1016/j.saa.2021.119468. Epub 2021 Jan 16.

Authors

Lili Sun¹, Hongmei Zhang¹, Yesheng Wang¹, Zhong Xiong², Xihui Zhao³, Yanzhi Xia⁴

Affiliations

¹ School of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China.
² School of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China; State Key Laboratory of Bio-fibers and Eco-textiles, Shandong Collaborative Innovation Center of Marine Biobased Fibers and Ecological Textiles, Institute of Marine Biobased Materials, Qingdao University, Qingdao 266071, China.
³ School of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China; State Key Laboratory of Bio-fibers and Eco-textiles, Shandong Collaborative Innovation Center of Marine Biobased Fibers and Ecological Textiles, Institute of Marine Biobased Materials, Qingdao University, Qingdao 266071, China. Electronic address: zhaoxihui@qdu.edu.cn.
⁴ State Key Laboratory of Bio-fibers and Eco-textiles, Shandong Collaborative Innovation Center of Marine Biobased Fibers and Ecological Textiles, Institute of Marine Biobased Materials, Qingdao University, Qingdao 266071, China.

PMID: 33508683
DOI: 10.1016/j.saa.2021.119468

Abstract

N-doped carbon dots (N-CDs) were successfully synthesized via simple one-step hydrothermal carbonization using chitosan as carbon and nitrogen sources. The obtained N-CDs contained a variety of functional groups on the NCDs surface, and exhibited excitation-independent behavior and strong blue fluorescence with a relatively higher fluorescence quantum yield (QY = 35%). It also presented excellent water solubility, resistance to pH change, high ion strength and UV irradiation. Since the fluorescence of the N-CDs could be selectively quenched by NO₂^-, they could act as a fluorescent sensor for the determination of NO₂^- in real tap water and lake water samples with a wide linear range (1-500 μM) and low detection limit (0.1 μM). They could also be used for bacterial imaging as multicolor fluorescent probes. The results indicated that N-CDs could be a promising candidate material for biomedical applications.

Keywords: Bacteria imaging; Chitosan; Fluorescence; N-doped carbon dots; Nitrite.

MeSH terms

Bacteria
Carbon
Chitosan*
Fluorescent Dyes
Nitrites
Nitrogen
Quantum Dots*

Substances

Fluorescent Dyes
Nitrites
Carbon
Chitosan
Nitrogen