Cranberry Beans Derived Carbon Dots as a Potential Fluorescence Sensor for Selective Detection of Fe³⁺ Ions in Aqueous Solution

Abstract

Recently, synthesis, characterization, and application of carbon dots have received much attention. Natural products are the effectual carbon precursors to synthesize carbon dots with fascinating chemical and physical properties. In this study, the fluorescent sensor of carbon dots derived from cranberry beans without any functionalization and modification was developed. The carbon dots were prepared with a cheap, facile, and green carbon precursor through a hydrothermal treatment method. The synthetic process was toxic chemical-free, convenient, and environmentally friendly. To find the optimized synthetic conditions, the temperature, heating time duration, and carbon precursor weight were evaluated. The prepared carbon dots were characterized by UV light, transmission electron microscopy, Raman, Fourier transform infrared, UV–vis, and fluorescence spectroscopy. The resulting carbon dots exhibit stable fluorescence with a quantum yield of approximately 10.85%. The carbon dots emitted the broad fluorescence emission range between 410 and 540 nm by changing the excitation wavelength and were used for the detection of Fe3+ ions at the excitation of 380 nm. It is found that Fe3+ ions induced the fluorescence intensity quenching of the carbon dots stronger than other heavy metals and the Fe3+ ion detection can be achieved within 3 min. Spectroscopic data showed that the obtained carbon dots can detect Fe3+ ions within the wide concentration range of 30–600 μM with 9.55 μM detection limit.

Nitrogen-doped carbon dots for sensitive detection of ferric ions and monohydrogen phosphate by the naked eye and imaging in living cells

“…Today some carbon dots based on Fe 3+ sensing have been reported. [19][20][21][22][23][24][25][26][27][28][29][30] Unfortunately, due to the intrinsic drawbacks of carbon dots, these carbon dots need UV excitation and their Stokes shifts are small, [28][29][30] which seriously restrict their application in living system. As for HPO 4 2-, there is little report based on carbon dots for phosphate anions (H 2 PO 4 -/HPO 4 2-) detection so far.…”

On-off Fluorescent Switching of Excitation-independent Near-ultraviolet Emission Carbon Nanobelts for Ultrasensitive Detection Nimesulide in Pharmaceutical Tablet

“…30 Also, the red shifts of the π-π* transition absorption for C=C from ∼230 to ∼290 nm may be due to the incorporation of heteroatoms into the carbon skeleton. 30,31 Different from the most reported carbon nanodots, [32][33][34] the narrowed full width at the half maximum (∼40 nm) and the excitation-independent emission of the NFNCBs (Fig. 3B) may be ascribe to the content of the aromatic heterocyclic nitrogen of C=N and the surface of the N-containing groups, 35 which can be regulated through selecting the precursor and regulating the experimental condition during hydrothermal reactions.…”

Nitrogen-Doped Carbon Dots from Averrhoa carambola Fruit Extract as a Fluorescent Probe for Methyl Orange

“…This result may be due to the chemical constituents in the AC fruit extract reacted slowly at a low solvent volume percentage. Furthermore, the temperature and reaction time duration of hydrothermal treatment possess significant effects on the fluorescence nature of CDs [23]. The AC-NCDs exhibited the highest emission intensity with a higher hydrothermal temperature and longer reaction time duration as depicted in Figure S1b,c.…”