A universal facile synthesis of nitrogen and sulfur co-doped carbon dots from cellulose-based biowaste for fluorescent detection of Fe3+ ions and intracellular bioimaging

• Published in: Materials Science & Engineering C 2019-06, Vol.99, p.611-619
• Main Authors: Cheng, Chaoge, Xing, Malcolm, Wu, Qilin
• Format: Article
• Language: English
• Subjects: Biocompatibility; Carbon dots; Cellulose; Cellulose-based biowaste; Combustion; Cytotoxicity; Ferric ions; Fluorescence; Forming mechanism; Fourier transforms; Infrared spectroscopy; Intracellular; Intracellular bioimaging; Ions; Iron; Materials science; Medical imaging; Natural resources; Nitrogen; Nitrogen and sulfur co-doped carbon dots; Raman spectroscopy; Spectroscopy; Spectrum analysis; Stability; Sulfur; Sulfuric acid; Toxicity; Urea; Willow; X ray photoelectron spectroscopy
• ISSN: 0928-4931; 1873-0191
• DOI: 10.1016/j.msec.2019.02.003

Carbon dots (CDs), especially heteroatom doped CDs derived from natural resources, have attracted growing interest due to their multiple potential applications. In this work, nitrogen and sulfur co-doped CDs (N/S-CDs) with a high quantum yield of 13.3% were synthesized by a facile approach based on one-step combustion treatment of cellulose-based biowaste of willow catkin. Due to the existence of urea and sulfuric acid used in the combustion process, the generated yield of the obtained N/S-CDs was raised to be as high as 14.3%. N/S-CDs were characterized by high-resolution TEM, FT-IR spectroscopy, XPS spectroscopy and Raman spectroscopy. The formation mechanism of N/S-CDs was also explored. These N/S-CDs with an average diameter of 7.3 nm demonstrated superior photo-stability, low cytotoxicity, pH stability and could be used for selective and sensitive detection of Fe3+ ions. Furthermore, based on their favorable feature of excellent biocompatibility and Fe3+ ions detection capability, the use of such N/S-CDs for intracellular Fe3+ ions detection application was also demonstrated. [Display omitted] •Nitrogen and sulfur co-doped carbon dots (N/S-CDs) were quickly prepared from cellulose-based biowaste.•The synthesized N/S-CDs exhibited excellent photo-stability, relatively high quantum yield and high generated yield.•The synthesized N/S-CDs were successfully applied in the field of Fe3+ ions detection and bioimaging.