Carbon Letters
·
2025
·
IF 5.8
Hu Chaoshuai,Liu Yuanxin,Zhang Jian,Zhu Yaming,Yin Xitao,Zhao Xuefei
Using durian shell as a carbon source and triethanolamine as a nitrogen dopant, nitrogen-doped carbon dots (N-CDs) were prepared via the hydrothermal method. First, by exploring different reaction times, reaction temperatures, and carbon source/dopant ratios to synthesize nitrogen-doped carbon dots, it is concluded that the best process conditions are 200 ℃, reaction time being 15h, and the dopant addition amount being 2mL. Structure and characteristics of the synthesized CDs were analyzed using X-ray photoelectron spectroscopy, Fourier-transform infrared, fluorescence (FL), ultraviolet–visible absorption, and Raman spectra. The N-CDs showed blue FL with a quantum efficiency of 4.28%. The FL characteristics of the N-CDs were utilized for ion detection, which demonstrated that \({\text{MnO}}_{4}^{ - }\) and \({\text{Cr}}_{{2}} {\text{O}}_{7}^{2 - }\) ions caused distinct FL quenching through static quenching, while other ions had no significant quenching effect. The detection limits for \({\text{MnO}}_{4}^{ - }\) and \({\text{Cr}}_{{2}} {\text{O}}_{7}^{2 - }\) were 37.5 and 46.2 nM, respectively. The N-CDs were subsequently employed to detect these ions in actual water samples, producing satisfactory results. Therefore, the preparation of N-CDs using durian shell as raw material and its application in practical detection work have good application feedback, which not only provides a new way for the reuse of fruit and vegetable wastes but also provides a new detection means for environmental monitoring pollutants.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Yu Wu,Lingchi Zeng,Yancheng Zheng,Fuchang You,Xuejin Liu
In this study, nitrogen-doped carbon dots (N-CDs) were synthesized via a one-step hydrothermal method using pectin polysaccharide as the carbon source, with 1-hexylamine, 1,2-diaminocyclohexane, and diethylenetriamine as individual nitrogen sources. The chemical composition, fluorescence properties, and morphology of the synthesized N-CDs were characterized. Their corrosion inhibition performance on N80 steel in 1 M H 2 SO 4 was evaluated using electrochemical analyses and weight loss experiments. Tafel and EIS analyses demonstrated that at a concentration of 200 mg/L, the maximum inhibition efficiencies of PHA-CDs, PCA-CDs, and PDA-CDs, synthesized using monoamine, diamine, and triamine as nitrogen sources, were 75.3 %, 90.1 %, and 95.4 %, respectively. The inhibition efficiency increased with the total nitrogen and pyrrolic N content in the N-CDs, corresponding to the choice of nitrogen source. Weight loss experiments further confirmed these trends. Additionally, the N-CDs were found to act as mixed-type inhibitors with a predominant anodic inhibition effect and are classified as predominantly chemisorptive. The adsorption behavior adhered to the Langmuir adsorption model, where coordination complexes formed between pyrrolic N and metal Fe increase the surface coverage of the adsorption film, thereby enhancing corrosion resistance.
研究领域:
材料科学
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电化学
·
绿色化学
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DOI
高影响因子
JOURNAL OF FLUORESCENCE
·
2024
·
IF 2.6
Chen Xian,Zhang Menghan,Zheng Lang,Deng Xiaoqin,Chen Qiang,Han Wendi,Huang Zhengjun,Weng Shaohuang
The establishment of a convenient and efficient testing method is crucial and needed for the monitoring of diosmin. In this study, nitrogen doped carbon dots (N-CDs) with the particle size distribution of 2.5–5.7 nm and the average diameter of 4.1 nm were successfully synthesized using a simple strategy. N-CDs exhibited excellent and stable fluorescence performance with the quantum yield of 22.33%. Correspondingly, a fluorescence analytical method was developed for diosmin determination using N-CDs as probe. UV-vis absorbance spectroscopy and the evaluation of internal filtering parameters verified that the mechanism causing the quenching of N-CDs was an internal filtering effect (IFE). The concentration of diosmin can be directly evaluated based on the quenched fluorescence intensities. After optimizing experimental conditions, it was found that the fluorescence quenching efficiency ((F 0 -F)/F 0 ) of N-CDs exhibited a good linear relationship with the concentration of diosmin (C Diosmin ) in the range of 3.0–50 µg/mL. The limit of detection (LOD) was 0.86 µg/mL based on 3σ/slope ( n = 13). This method was successfully applied to accurately determine the content of diosmin in diosmin tablets and human plasma samples with good reproducibility. It stands out for its simplicity, speed, and acceptable determination performance.
研究领域:
药物分析
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生物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2023
·
IF 4.3
Mohammad Nazari Kalojeh,Roghayeh Hassanpour Sabet,Mir Ali Farajzadeh,Mohammad Reza Afshar Mogaddam,Elnaz Marzi Khosrowshahi,Mustafa Tuzen
A dispersive solid phase extraction procedure was established for the extraction of some pesticides from fruit juices and then it was combined with dispersive liquid-liquid microextraction for more enrichment of the analytes. For this purpose, 40 mg of zeolitic imidazolate framework-carbon dot composite was dispersed into the sample solution as the sorbent via vortex agitation. After that, the sorbent was collected by centrifugation and the supernatant was wasted. Then, 1 mL of a water-soluble organic solvent (acetone) was added onto the sorbent as the elution solvent. After desorption of the analytes from the sorbent surface, the eluate was mixed with a water-immiscible organic solvent (1,1,2-trichloro-1,2,2 trifluoroethane) at µL-level (45 µL) and the mixture was quickly injected into 5 mL deionized water. The resulting cloudy mixture was centrifuged and 1 µL of the sedimented phase was injected into a gas chromatography-flame ionization detection system. After the optimization of the method, its validation was evaluated. The data showed that the limits of detection and quantification obtained by this method were in the ranges of 0.22–0.72 and 0.73–2.40 ng mL −1 , respectively. The plotted calibration curves were linear in the range of 0.73–1000 µg L −1 for all analytes. High enrichment factors (375−445), and extraction recoveries (75–89%), and negligible matrices effect were obtained for the investigated analytes by the introduced method. Also, the obtained data showed that all samples were free of the analytes.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
MICROCHEMICAL JOURNAL
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2024
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IF 4.9
Sai Zhang,Ruixi Yang,Yaping Wang,Qinqin Gao,Langhong Wang,Guisheng Zhou,Qinglin Sheng
In recent years, food-borne pathogen Pseudomonas cocovenenans have caused many food safety incidents. Therefore, the detection of toxoflavin produced by the bacteria has aroused widespread attention. In this study, two fluorescent sensors were prepared using nitrogen-doped carbon dots (NCDs) materials as precursors: (1) Luminol-functionalized NCDs were synthesized by NHS-EDC reaction, and L-NCDs fluorescence sensor was constructed for the detection of toxoflavins in actual food samples. The linear range of the L-NCDs fluorescence sensor is 0.1–50 μM, the detection limit is 0.05 μM and the excitation wavelength is 375 nm. (2) The NCDs-CMC fluorescent film sensor was constructed by incorporating NCDs into sodium carboxymethyl cellulose. It was excited at a wavelength of 385 nm for visual detection of toxoflavin. The film sensor has a linear range of 1–60 μM and a detection limit of 0.45 μM. The results showed that the method has good sensitivity and reliability. This study extends the application of NCDs-based fluorescence sensing to detect toxoflavin. It enables simple, rapid, low-cost sensitive detection and visual monitoring of toxoflavin. Additionally, it offers a fast and convenient new technology for preventing and controlling Pseudomonas cocovenenans contamination in food.
研究领域:
分析化学
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食品科学
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微生物学
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2021
·
IF 8.128
Zheng Liu,Ruonan Jia,Feng Chen,Guilong Yan,Weiguo Tian,Jinming Zhang,Jun Zhang
Iron corrosion is a subject of great technological importance and extensive public concern. However, the highly efficient detection of iron corrosion at early stage is still a challenging task. Herein, bright fluorescent carbon dots (CDs) with superior response to Fe 3+ were prepared by simple solvothermal process based on citric acid and ammonia. The obtained CDs are able to rapidly, sensitively and selectively respond to Fe 3+ . The quantitative analysis showed that the CDs exhibited a linear response to Fe 3+ in the range of 10 to 300 µM, with a detection limit of 0.9 μM. And the fluorescence quenching of CDs was obvious enough to be detected by the naked eyes. Such promising responsiveness of CDs offers a great opportunity for real-time and visual detection of Fe 3+ during electrochemical corrosion process. In addition, due to the excellent stability and solubility of CDs, patterned papers and hydrogels have been fabricated utilizing cellulose and PVA as matrices. The as-prepared biocompatible, environmental-friendly and disposable CDs based fluorescent materials were successfully used for detecting the degree of iron corrosion. This could provide a simple and visual strategy for monitoring the safety of structural metal materials.
研究领域:
材料科学
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电化学
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分析化学
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DOI
高影响因子
NANOTECHNOLOGY
·
2021
·Vol. 32
·期 17
·175604
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IF 3.874
Fan Liu,Yuan Jiang,HaiBao Shao,Chunlei Wang,Shuhong Xu,Rong Zhang
Precise control of the structure and bonds of doped carbon dots (CDs) is important, so that their fluorescence can be tuned as desired. Up until now, there has been a lack of effective ways to control the bonds of doped CDs. In this article, we show that the fluorescence of B/N-doped carbon dots (B/N-CDs) can be precisely tuned just by controlling their precursors' pH values. The prepared B/N-CDs exhibit two emission bands, including one emission peak at around 450 nm due to the defect state caused by low sp2 hybridization of carbon atoms, as well as another emission peak at around 360 nm caused by the B-N bond. The results for the ratio of the maximum intensity of the two emission peaks above show a linear relationship. Meanwhile, the role of the pH value of the precursors on the luminescence of B/N-CDs is deeply studied. On the one hand, the pH value affects the bonding process of CDs. N-H bonds tend to form at a low pH value, while more competitive B-N bonds exist at much higher pH value, leading to the pH-dependent intensity of the 360 nm emission band. On the other hand, a high pH value causes higher crystallinity, thus suppressing defect-state fluorescence at 450 nm. The dual effects of pH lead to precisely controlled dual-emission intensities as well as ratiometric fluorescence.
研究领域:
材料科学
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化学
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产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 29
·22343-22349
·
IF 3.84
Zhao Chen,Xiaochi Wang,Hua Li,Chao Li,Qinghua Lu,Guang Yang,Jiangang Long,Lingjie Meng
A facile but effective bottom-up method for the mass preparation of N-doped carbon dots (N–C-dots) was developed by the direct heating of a solid mixture of folic acid (FA) and sodium citrate (SC) for several minutes at 300 °C. The nitrogen content of the resulting N–C-dots could be easily and precisely tuned from 0% to 14% by adjusting the SC to FA mass ratio. Uniform N–C-dots with honeycomb-like ordered structures were obtained, with sizes ranging from 1 to 3 nm in diameter. The N-doping content affected not only the emission quantum yield but also the emission wavelength. The N–C-dots emitted strong blue-green fluorescence based on the excitation wavelength and N-doping content. Because of their excellent water solubility, low toxicity, powerful fluorescence, and high resistance to photobleaching, the N–C-dots can enter various cells and serve as ideal candidates for multicolour cell imaging.
研究领域:
材料科学
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生物医学工程
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化学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2016
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IF 4.758
Guojuan Ren,Qi Zhang,Shuang Li,Shanshan Fu,Fang Chai,Chungang Wang,Fengyu Qu
A kind of biocompatible fluorescent nitrogen doped carbon quantum dots (NCDs) has been synthesized using uric acid as raw material through a facile, effective and green thermal treatment method in one pot. The surface morphology and optical properties of the synthesized NCDs were characterized. Without further chemical modification, the NCDs emit bright blue fluorescence with a high quantum yield of 56% due to the enhancement effect of N dopant atoms on a surface of carbon quantum dots. Owing to the strong blue fluorescence, negligible toxicity and the special response of heavy metal ions, the NCDs have been used as a fluorescence probe for sensitive and selective detection of Hg 2+ and Ag + ions with detection limit of 4.8 nM and 1 nM, respectively. Moreover, it was successfully applied to determination of Hg 2+ and Ag + in real environmental water samples, which offers the advantages of simplicity and cost efficiency.
研究领域:
化学
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环境科学
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生物医学
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产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2021
·
IF 4.098
Baoqiang Liu,Shanshan Wei,Enqi Liu,Hongyuan Zhang,Pengju Lu,Jiali Wang,Guoying Sun
The folic acid (FA) level in human body can be used as an indicator for body's normal physiological activities and offer insight into the growth and reproduction of the body's cells. But the abnormal level of FA can cause some diseases. Herein, we designed a simple and convenient approach to prepare fluorescent N-doped carbon dots (N-CDs) for the FA detection. These N-CDs have excellent hydrophilicity, high photostability, and outstanding biocompatibility, as well as excitation-independent emission behavior with typical excitation/emission peaks at 295 nm/412 nm. Upon the existence of FA, the fluorescence emission spectrum of N-CDs was significantly quenched through the synergy of static quenching mechanism and internal filtering effect (IFE). Under optimal conditions, the limit of detection was 28.0 nM (S/N = 3) within the FA concentration range of 0–200.0 μM. In addition, N-CDs were successfully employed to detect FA in real samples such as urine and fetal bovine serum (FBS), with a recovery rate of 99.6%-100.7% for quantitative addition. Furthermore, cell experiments confirmed the low toxicity and the cell imaging performance of these N-CDs, indicating that the obtained N-CDs could be served as a credible quantitative probe for FA analysis in the field of biosensing.
研究领域:
生物传感
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分析化学
·
细胞生物学
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产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Junfeng Chen,Ying zhang,XiaoJuan Li,Yanan Wang,Chang Ma,Minghui Guo
Photocatalytic degradation of organic pollutants is a widely used technology. Constructing oxygen vacancies , compounding other materials, and adjusting semiconductor morphology are effective ways to promote the performance of photocatalysis . In this study, ultrathin NCDs/BiOBr nanosheets with excellent photocatalytic ability were prepared. The triple role of NCDs in NCDs/BiOBr synthesis was revealed: controlling the thickness of the nanosheets , increasing the oxygen vacancy concentration, and regulating the band gap structure. Rhodamine B and tetracycline were degraded by the samples in visible light to examine their photocatalytic properties. The samples with the highest electron transfer efficiency were verified by optical and electrochemical characterization. As-synthesized NCDs/BiOBr catalysts exhibited good degradation in different water samples，indicating the ability of the samples for practical applications. In addition, the intermediates and possible degradation pathways of the prepared catalysts for the degradation of TC processes were also analyzed in depth. The electron transfer pathway and photocatalytic mechanism of NCDs/BiOBr were proposed in combination with free radical detection and energy band calculation.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
CARBON
·
2025
·
IF 11.6
Menghui Chi,Lingwen Gu,Ke Liu,Jing Lin,Qian Wang,Bing Yu,Ziyi Wang,Xueyun Fu,Daohao Li,Guiqiu Zhao,Cui Li
The photocatalytic antifungal strategy has attracted much attention in the field of fungicidal therapy due to its efficient therapeutic efficacy and avoidance of drug resistance. However, exploring safe and efficient photocatalysts remains an urgent challenge. In this work, nitrogen-doped carbon dots (N-CDs) combined with titanium dioxide (TiO 2 ) nanomaterials were synthesized by a hydrothermal method to exert a photocatalytic antifungal effect under sunlight irradiation. Compared with carbon dots/TiO 2 without N-doped modification, employing N doping to fabricate N-CDs/TiO 2 photocatalyst could further markedly optimize the bandgap structure of TiO 2 , improve the absorption of the solar spectrum and accelerate the electron-hole pairs separation, thereby greatly enhancing the photocatalytic reaction and antifungal effect. Remarkably, in the photocatalytic antifungal reaction, N-CDs/TiO 2 produces more oxygen radicals such as •OH and •O 2 − to rapidly hinder the germination of Aspergillus fumigatus hyphae and the formation of fungal biofilm. Additionally, the incorporation of N-CDs and TiO 2 possesses the great biocompatibility. Overall, this study proves that employing N-CDs/TiO 2 nanomaterials can be a promising and efficient therapeutic method against fungal infections.
研究领域:
微生物学
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材料科学
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医学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）