title: Fluorescent carbon nanodots for sensitive and selective detection of tannic acid in wines.
abstract: Herein we describe an easy one step synthesis of carbon nanodots (C-dots) by thermal carbonization of 6-bromohexylboronic acid using two different amine compounds, polyethyleneglycol bis(3-aminopropyl (PEGA) and 1,2-aminopropane (DPA), at 180 °C in atmospheric oxygen. The as-synthesized C-dots were characterized by FTIR, HRTEM, NMR and fluorescence. The C-dots prepared using PEGA showed a strong emission at 440 nm with excitation at 362 nm. These C-dots exhibited analytical potential as sensing probes for tannic acid (TA) determination. pH effect, interferences, and analytical performance of the method were investigated. The method was found effective in the linear concentration range from 0.1 to 10 mg L(-1) TA achieving a limit of detection equal 0.018 mg L(-1) TA. The applicability of the method was demonstrated by direct measurements of TA in red and white wine samples. Validation of the method was achieved by spiking the wine samples with different standard TA concentrations obtaining recoveries in the range (90-112.5%). A probable mechanism by which TA quenched the C-dots fluorescence was proposed.
authors.affiliation: Chemistry Department, Faculty of Science, Damanhur University, Damanhur, Egypt; Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, c/JuliánClavería, 8, Oviedo 33006, Spain.
authors.forename: Gaber Hashem Gaber
authors.initials: GH
authors.lastname: Ahmed
authors.affiliation: Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, c/JuliánClavería, 8, Oviedo 33006, Spain. Electronic address: rbadia@uniovi.es.
authors.forename: Rosana Badía
authors.initials: RB
authors.lastname: Laíño
authors.affiliation: Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, c/JuliánClavería, 8, Oviedo 33006, Spain.
authors.forename: Josefa Angela García
authors.initials: JA
authors.lastname: Calzón
authors.affiliation: Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, c/JuliánClavería, 8, Oviedo 33006, Spain. Electronic address: medg@uniovi.es.
authors.forename: Marta Elena Díaz
authors.initials: ME
authors.lastname: García
mesh_terms: D001897:Boronic Acids / Q000737:chemistry; D002244:Carbon / Q000737:chemistry*; D005456:Fluorescent Dyes; D006863:Hydrogen-Ion Concentration; D057230:Limit of Detection; D049329:Nanostructures / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011437:Propylamines / Q000737:chemistry; D045663:Quantum Dots / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013634:Tannins / Q000302:isolation & purification*; D014920:Wine / Q000032:analysis*
chemical_list: D001897:Boronic Acids; D005456:Fluorescent Dyes; C424387:O,O'-bis(2-aminopropyl)polyethylene glycol; D011437:Propylamines; D013634:Tannins; D011092:Polyethylene Glycols; D002244:Carbon
keywords: Carbon nanodots; Tannic acid; Wines