title: N-doped carbon dots derived from bovine serum albumin and formic acid with one- and two-photon fluorescence for live cell nuclear imaging.
abstract: Carbon dots with both one- and two-photon fluorescence have drawn great attention for biomedical imaging. Herein, nitrogen-doped carbon dots were facilely developed by one-pot hydrothermal method using bovine serum albumin and formic acid as carbon sources. They are highly water-soluble with strong fluorescence when excited with ultraviolet or near infrared light. The carbon dots have a diameter of ~8.32 nm and can emit strong two-photon induced fluorescence upon excitation at 750 nm with a femtosecond laser. X-ray photoelectron spectrometer analysis revealed that the carbon dots contained three components, C, N and O, corresponding to the peak at 285, 398 and 532 eV, respectively. The Fourier-transform infrared spectroscopy analysis revealed that there are carboxyl and carboxylic groups on the surface, which allowed further linking of functional molecules. pH stability study demonstrated that the carbon dots are able to be used in a wide range of pH values. The fluorescence mechanism is also discussed in this study. Importantly, these carbon dots are biocompatible and highly photostable, which can be directly applied for both one- and two-photon living cell imaging. After proper surface functionalization with TAT peptide, they can be used as fluorescent probes for live cell nuclear-targeted imaging.
authors.affiliation: Liaoning Province Key Laboratory of Seafood Science and Technology, National Engineering Research Center of Seafood, School of Food Science and Technology, Dalian Polytechnic University, 1 Qinggongyuan, Ganjingzi District, Dalian 116034, China. Electronic address: 2468750030@qq.com.
authors.forename: Mingqian
authors.initials: M
authors.lastname: Tan
authors.affiliation: School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China; Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
authors.forename: Xintong
authors.initials: X
authors.lastname: Li
authors.affiliation: Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Wu
authors.affiliation: Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
authors.forename: Beibei
authors.initials: B
authors.lastname: Wang
authors.affiliation: School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wu
mesh_terms: D000818:Animals; D002244:Carbon / Q000737:chemistry*; D002417:Cattle; D045744:Cell Line, Tumor; D005453:Fluorescence; D005561:Formates / Q000737:chemistry*; D006801:Humans; D046529:Microscopy, Electron, Transmission; D056951:Photoelectron Spectroscopy; D012710:Serum Albumin, Bovine / Q000737:chemistry*
chemical_list: D005561:Formates; C030544:formic acid; D012710:Serum Albumin, Bovine; D002244:Carbon
keywords: Bioimaging; Carbon dots; Nitrogen-doped; Nuclear-targeted imaging; Two-photon-induced fluorescence