Preparation of carbon dots with long-wavelength and photoluminescence‐tunable emission to achieve multicolor imaging in cells

• Published in: Optical materials Vol. 88; pp. 353 - 358
• Main Authors: Cheng, Chaoge, Xing, Malcolm, Wu, Qilin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2019
• Subjects: Carbon dots; Multi-color bioimaging; Photoluminescence‐tunable emission; Photoluminescence‐tunable emission; Multi-color bioimaging; Carbon dots
• ISSN: 0925-3467; 1873-1252
• DOI: 10.1016/j.optmat.2018.12.007

Most carbon dots (CDs) derived from natural biowastes show emission limitedly in the blue range. This work applied urea and sulfuric acid as dopants to assist the carbonization of cellulose-based biowaste willow catkin. Then a facile chemical cutting method was developed for scalable production of CDs. Under excitation at a single-wavelength of 360 nm, the aqueous solutions of CDs obtained at different cutting temperatures (100, 120, and 140 °C) exhibited strong blue (486 nm), green (522 nm) and yellow (545 nm) emission, respectively. The as-prepared CDs also exhibited excitation-independent emission behaviors and high photostability in different pH and ionic strength. Furthermore, these long-wavelength and photoluminescence-tunable CDs were successfully applied to multicolor bioimaging in Hela cells, indicating their potential toward multimodal sensing applications in biological environment. [Display omitted] •Urea and sulfuric acid were creatively used as dopant to prepare carbon dots (CDs) from cellulose-based biowaste.•By simply altering the chemical cutting temperatures, the emission color of the CDs can be tuned from blue to yellow.•Multi-color bioimaging in Hela cells can be obtained.