title: One pot synthesis of intriguing fluorescent carbon dots for sensing and live cell imaging.
abstract: We report a simple one-pot synthesis of highly fluorescent carbon dots (CDs) via modified hydrothermal (MHT) treatment of alkaline solution of dopamine and cysteine. These CDs (λex=320 nm, λem=390 nm, and quantum yield ∼ 5.1%) are of ∼ 2-3 nm in diameter. Further attempt of synthesizing CDs in some common water-miscible solvents ends up the fact that the MHT product from acetone medium is nonfluorescent. However, CDs, produced in aqueous medium, are so stable that they can be dried as a deliverable solid (WCD) without any alteration of fluorescing property if reversibly dispersed in water. Fluorescence of WCD is quenched selectively in acetone. Quenching occurs presumably due to the disruption of radiative recombination along with the hindrance in quantum confinement of the emissive energy traps to the particle surface. Successive quenching of fluorescence of WCD in different acetone concentration admixed in water paves the way to selective acetone sensing (LOD=8.75 × 10(-7) M). The synthesized CDs (in aqueous medium) are cytocompatible and are efficient fluorescent probe for cell imaging. Only living cells are recognized exclusively from fluorescence imaging leaving aside dead cells, while cells are treated with CDs.
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Kharagpur 721302, India.
authors.forename: Jayasmita
authors.initials: J
authors.lastname: Jana
authors.affiliation: Department of Chemistry, Furman University, Greenville, SC 29613, United States.
authors.forename: Mainak
authors.initials: M
authors.lastname: Ganguly
authors.affiliation: School of Medical Science & Technology, Indian Institute of Technology, Kharagpur 721302, India.
authors.forename: Bodhisatwa
authors.initials: B
authors.lastname: Das
authors.affiliation: School of Medical Science & Technology, Indian Institute of Technology, Kharagpur 721302, India.
authors.forename: Santanu
authors.initials: S
authors.lastname: Dhara
authors.affiliation: Department of Applied Chemistry, Tokyo University of Science, Tokyo 1628601, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Negishi
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Kharagpur 721302, India. Electronic address: tpal@chem.iitkgp.ernet.in.
authors.forename: Tarasankar
authors.initials: T
authors.lastname: Pal
mesh_terms: D000096:Acetone / Q000032:analysis / Q000737:chemistry; D000818:Animals; D002244:Carbon / Q000737:chemistry*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival; D060326:Chemistry Techniques, Synthetic; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D005456:Fluorescent Dyes / Q000138:chemical synthesis* / Q000737:chemistry* / Q000633:toxicity; D057230:Limit of Detection; D051379:Mice; D057054:Molecular Imaging / Q000379:methods*; D053758:Nanoparticles / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D014867:Water / Q000737:chemistry
chemical_list: D005456:Fluorescent Dyes; D012997:Solvents; D014867:Water; D000096:Acetone; D002244:Carbon; D004121:Dimethyl Sulfoxide
keywords: Acetone; Carbon dots; Cell imaging; Cytocompatible; Fluorescence; Sensing