Microwave prepared nitrogen and sulfur co-doped carbon quantum dots for rapid determination of ascorbic acid through a turn off–on strategy

Hamid, Mohamed A. Abdel; Elagamy, Samar H.; Gamal, Aya; Mansour, Fotouh R.

doi:10.1016/j.saa.2023.122440

Cited by 21 publications

(6 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…From Table I, the fluorescence quantum yields were 0.22 for 1-CQDs, 0.29 for 2-CQDs and 0.529 for 3-CQDs. And from the, 18 the fluorescence quantum yield of quinine sulfate is 0.54. And the reason why quinine sulfate was chosen as the standard substance was because of its stable nature and high fluorescence yield, but as shown in Table I, the fluorescence quantum yield of 3-CQDs was 0.529, Which is close to the fluorescence quantum yield of quinine sulfate.…”

Section: Resultsmentioning

confidence: 99%

“…9 Compared to conventional inorganic and organic fluorescent materials, 10,11 the excellent fluorescence properties and low cytotoxicity of CQDs enable their use for bioimaging. 12,13 Ding et al 14 used surface-modified CQDs to label Hela cells, and based on experimental results found that the half lethal concentration of CQDs at 24 h was more than one hundred times the concentration required for cell imaging.CQDs are synthesized from various sources, such as 1,2-diamino-4-bromobenzene, 15 peony pollen, 16 citric acid and nile blue, 17 and cysteine, 18 which are used to synthesize CQDs, and different precursors confer different physicochemical and functional properties to CQDs. 19 Different nitrogen sournctional properties.…”

mentioning

confidence: 99%

“…Fluorescence quantum yields of CQDs.-The fluorescence quantum yield (QY) is the ratio of the number of photons of light emitted after the excitation light is absorbed by the fluorescent material to the number of photons of excitation light absorbed by the material in a certain time.Fluorescence quantum yields were measured by comparing the absorbance values and integrated areas of 1-CQDs, 2-CQDs and 3-CQDs with the reference quinine sulfate (QS).The absorption and emission spectra of quinine sulfate solution and CQDs solution were measured and analyzed by excitation with UV light. Their quantum yields were calculated according to the equation: 18,23…”

mentioning

confidence: 99%

See 2 more Smart Citations

Preparation of Highly Luminescent Carbon Quantum Dots and Study of Bioimaging

Fu,

Zhang,

et al. 2023

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

Using ammonium citrate as the carbon source and urea, ammonia and ethylenediamine as the nitrogen sources, CQDs with different nitrogen sources were prepared by hydrothermal method, and the preparation conditions were optimized to obtain CQDs with the best fluorescence performance for three different nitrogen sources.The fluorescence colors of the three CQDs were not significantly different, all of them were blue, indicating that different nitrogen sources did not have significant differences on the fluorescence color, but had some effects on the fluorescence intensity, and the yields of 1-CQDs, 2-CQDs and 3-CQDs were 0.22, 0.29 and 0.529, respectively.The UV, natural light, pH and ionic stability of CQDs with different nitrogen sources were investigated, and the results showed that 3-CQDs have UV, natural light and ionic stability, and all three CQDs have pH instability.The MTT method shows that 3-CQDs have lower cytotoxicity than the other two CQDs, and the bioimaging experiments show that 3-CQDs bind to yeast in greater numbers and have stronger fluorescence intensity, which proves that they are more suitable for bioimaging, laying a theoretical foundation for the bioimaging of CQDs at a later stage.

show abstract

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Preparation of Highly Luminescent Carbon Quantum Dots and Study of Bioimaging

Fu,

Zhang,

et al. 2023

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…Furthermore, CDs have shown potential in controlled drug delivery [19,20], anticancer therapy [18,[21][22][23], solar cells [24][25][26], and, recently, as endoplasmic reticulum in situ antioxidants [27]. Several methods have been developed for the synthesis of CDs, including arc discharge [28], electrophoresis [29], hydrothermal synthesis [2,[30][31][32], electrochemical methods [33,34], ultrasonic-assisted synthesis [35], and microwave-assisted synthesis [36][37][38].…”

Section: Introductionmentioning

confidence: 99%

“…For example, Mansour et al reported the microwave-assisted synthesis of CDs using a high-concentrated L-cysteine solution in a multimodal microwave reactor for 60 s at 800 W [37]. While their method was successful in producing CDs, a lack of control over the parameters of synthesis led to different size distributions and forms of the nanoparticles and the formation of large precipitates even after dialysis was performed.…”

Section: Introductionmentioning

confidence: 99%

One-Pot, Optimized Microwave-Assisted Synthesis of Difunctionalized and B–N Co-Doped Carbon Dots: Structural Characterization

Ibarra-Prieto,

Garcia-Garcia,

Aguilera-Granja

et al. 2023

Nanomaterials

View full text Add to dashboard Cite

In this work, we employed a novel microwave-assisted synthesis method to produce nitrogen and boron co-doped carbon dots (B–N co-doped CDs). To achieve optimal synthesis, we conducted a comprehensive parameter modulation approach, combining various synthesis temperatures, times, and precursor concentrations, while keeping the power constant at 150 W and pH 5. Using maximum fluorescence emission as our response variable, the best conditions were identified as 120 °C, 3 min, and a precursor concentration of 1 mg/mL. Characterization using field emission scanning electron microscopy revealed these CDs to have a spherical morphology with an average size of 10.9 ± 3.38 nm. Further high-resolution transmission electron microscopy showed an interplanar distance of 0.23 nm, which is in line with prior findings of CDs that present a 0.21 nm distance corresponding to the (100) plane of graphite. Optical properties were ascertained through UV–vis absorption, identifying distinct π–π* and n–π* transitions. Fluorescence spectroscopy highlighted an emission peak at 375 nm when excited at 295 nm, achieving a quantum yield of 56.7%. Fourier-transform infrared spectroscopy and Raman spectroscopy analyses confirmed the boronic acid and amine groups’ presence, underscoring the graphitic nature of the core and the co-doping of boron and nitrogen. These empirical observations were compared with theoretical investigations through simulated Raman spectra, proposing a potential structure for the CDs. X-ray photoelectron spectroscopy further endorsed the co-doping of nitrogen and boron, along with the detection of the specified functional groups. All these characteristics could lend this nanomaterial to different types of applications such as fluorescent probes for a broad range of analytes and for fluorescent cell imaging.

show abstract

Fluorimetric determination of Vonoprazan via quenching of nitrogen and sulfur co‐doped carbon quantum dots: A rapid and sustainable analytical approach

Barseem,

Elshahawy,

Elagamy

2024

Luminescence

Self Cite

View full text Add to dashboard Cite

In this study, an environmentally sustainable fluorimetric method for determination of Vonoprazan fumarate (VON) in dosage forms using nanoprobes consisting of nitrogen and sulfur co‐doped carbon quantum dots (N, S‐CQDs). The N, S‐CQDs were prepared through a microwave‐assisted method in 30 s. The resulting N, S‐CQDs were characterized using transmission electron microscopy (TEM), high‐resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), and X‐ray photoelectron spectroscopy (XPS). They exhibit fluorescence emission at 460 nm after excitation at 385 nm with a high quantum yield (60%). The analytical approach for VON determination relies on the quenching effect exerted by VON on the native fluorescence intensity of CQDs. The quenching mechanism was investigated using Stern–Volmer plots. The proposed method demonstrates linearity across a concentration range 10–80 μM (4.6–36.8 μg/mL) with corresponding limits of detection and quantitation calculated as 2.17 μM (0.99 μg/mL) and 6.58 μM (3.02 μg/mL), respectively. The method has been effectively utilized for the determination of VON in the pharmaceutical samples. Statistical comparison with reported RP‐HPLC has been performed to verify the accuracy and precision of the developed method. The environmental sustainability of the developed method has been thoroughly examined through various greenness metrics.

show abstract

Microwave prepared nitrogen and sulfur co-doped carbon quantum dots for rapid determination of ascorbic acid through a turn off–on strategy

Cited by 21 publications

References 36 publications

Preparation of Highly Luminescent Carbon Quantum Dots and Study of Bioimaging

Preparation of Highly Luminescent Carbon Quantum Dots and Study of Bioimaging

One-Pot, Optimized Microwave-Assisted Synthesis of Difunctionalized and B–N Co-Doped Carbon Dots: Structural Characterization

Fluorimetric determination of Vonoprazan via quenching of nitrogen and sulfur co‐doped carbon quantum dots: A rapid and sustainable analytical approach

Contact Info

Product

Resources

About