Multicolor polymeric carbon dots: synthesis, separation and polyamide-supported molecular fluorescence

Bo Zhi, Xiaoxiao Yao, Meng Wu, Arielle Mensch, Yi Cui, Jiahua Deng, Juan J. Duchimaza-Heredia, Kasidet Jing Trerayapiwat, Thomas Niehaus, Yoshio Nishimoto, Benjamin P. Frank, Yongqian Zhang, Riley E. Lewis, Elaine A. Kappel, Robert J. Hamers, Howard D. Fairbrother, Galya Orr, Catherine J. Murphy, Qiang Cui, Christy L. Haynes

Research output: Contribution to journalArticlepeer-review

Abstract

Multicolor carbon dots (CDs) have been developed recently and demonstrate great potential in bio-imaging, sensing, and LEDs. However, the fluorescence mechanism of their tunable colors is still under debate, and efficient separation methods are still challenging. Herein, we synthesized multicolor polymeric CDs through solvothermal treatment of citric acid and urea in formamide. Automated reversed-phase column separation was used to achieve fractions with distinct colors, including blue, cyan, green, yellow, orange and red. This work explores the physicochemical properties and fluorescence origins of the red, green, and blue fractions in depth with combined experimental and computational methods. Three dominant fluorescence mechanism hypotheses were evaluated by comparing time-dependent density functional theory and molecular dynamics calculation results to measured characteristics. We find that blue fluorescence likely comes from embedded small molecules trapped in carbonaceous cages, while pyrene analogs are the most likely origin for emission at other wavelengths, especially in the red. Also important, upon interaction with live cells, different CD color fractions are trafficked to different sub-cellular locations. Super-resolution imaging shows that the blue CDs were found in a variety of organelles, such as mitochondria and lysosomes, while the red CDs were primarily localized in lysosomes. These findings significantly advance our understanding of the photoluminescence mechanism of multicolor CDs and help to guide future design and applications of these promising nanomaterials.

Original languageEnglish (US)
Pages (from-to)2441-2455
Number of pages15
JournalChemical Science
Volume12
Issue number7
DOIs
StatePublished - Feb 21 2021

ASJC Scopus subject areas

  • Chemistry(all)

Fingerprint Dive into the research topics of 'Multicolor polymeric carbon dots: synthesis, separation and polyamide-supported molecular fluorescence'. Together they form a unique fingerprint.

Cite this