Synthesis of Fluorescent Carbon Dots and Their Application in Ascorbic Acid Detection

Abstract

Water-soluble fluorescent carbon dots (CDs) were synthesized by a hydrothermal method using citric acid as the carbon source and ethylenediamine as the nitrogen source. The repeated and scale-up synthetic experiments were carried out to explore the feasibility of macroscopic preparation of CDs. The CDs/Fe3+ composite was prepared by the interaction of the CDs solution and Fe3+ solution. The optical properties, pH dependence and stability behavior of CDs or the CDs/Fe3+ composite were studied by ultraviolet spectroscopy and fluorescence spectroscopy. Following the principles of fluorescence quenching after the addition of Fe3+ and then the fluorescence recovery after the addition of asorbic acid, the fluorescence intensity of the carbon dots was measured at λex = 360 nm, λem = 460 nm. The content of ascorbic acid was calculated by quantitative analysis of the changing fluorescence intensity. The CDs/Fe3+ composite was applied to the determination of different active molecules, and it was found that the composite had specific recognition of ascorbic acid and showed an excellent linear relationship in 5.0–350.0 μmol·L−1. Moreover, the detection limit was 3.11 μmol·L−1. Satisfactory results were achieved when the method was applied to the ascorbic acid determination in jujube fruit. The fluorescent carbon dots composites prepared in this study may have broad application prospects in a rapid, sensitive and trace determination of ascorbic acid content during food processing.

One-Step Synthesis of Nitrogen/Fluorine Co-Doped Carbon Dots for Use in Ferric Ions and Ascorbic Acid Detection

“…Table S4 presents the comparison of the current AA detection modes, linear ranges, and LODs from recent reports. Thus, the NFCDs prepared in the present work showed comparable LODs and linear ranges when compared with previous research [ 9 , 10 , 26 , 37 ].…”

“…On the other hand, ascorbic acid (AA), also named vitamin C, is one of the most important water-soluble vitamins in the human body. The excess or lack of AA would reduce the metabolism and redox and thus lead to various diseases [ 9 , 10 ]. Generally, the fluorescent materials applied for metal ions and AA detection are divided into several groups, including gold and silver nanoclusters [ 11 , 12 ], organic dyes [ 13 , 14 ], and so on [ 15 , 16 ].…”

A Continuously Tunable Full-Color Emission Nitrogen-Doped Carbon Dots and for Ultrasensitive and Highly Selective Detection of Ascorbic Acid

“…as 42.28 µmol/L (RSD = 0.20) in animal serum, which was consistent with a previous report. Additionally, three different concentrations (20,30,40 µmol/L) of AA were added into the serum and the performance of our F-NCDs was evaluated. As expected, the recovery rate was as high as 99.89~101.54% (RSD < 2.1%) (Table 3).…”

A facile imine-linked covalent organic framework doped with a carbon dot composite for the detection and removal of Hg2+ in surface water

“…The preparation of CDs 39 and TpPa-1 COF 40 were previously reported and are via a one-step hydrothermal method and a mechanical stirring method, respectively. TpPa-1 COF@CDs was synthesized by a reverse microemulsion method.…”