A Green, Economic “Switch-On” Sensor for Cefixime Analysis Based on Black Soya Bean Carbon Quantum Dots

2020 ◽  
Vol 103 (5) ◽  
pp. 1230-1236
Author(s):  
Yuecheng Zhang ◽  
Jingyuan Wang ◽  
Wenbo Wu ◽  
Chengjia Li ◽  
Hongyan Ma
Keyword(s):  
Quantum Dots ◽  
Bacterial Infections ◽  
Low Cost ◽  
High Sensitivity ◽  
Practical Method ◽  
Carbon Quantum Dots ◽  
Drug Analysis ◽  
Soya Bean ◽  
Simple Strategy ◽  
Biological Environment

Abstract Background Cefixime is a third-generation oral cephalosporin antibiotic widely used to treat bacterial infections. Typical methods for cefixime analysis use expensive instruments or sophisticated experimental procedures, and thus a sensitive and practical method is urgently needed for cefixime detection and analysis. Objective To develop a sensitive and robust cefixime “switch-on” sensor based on carbon quantum dots (CQDs). Methods In this study, black soya beans were used as an inexpensive carbon source for a “green” synthesis of fluorescent black soya bean (BS)-carbon quantum dots (CQDs). The fluorescence of these particles could be efficiently quenched by Ce(IV)due to the ground state recombination and electron transfer (ET) between Ce(IV)and BS-CQDs. In the presence of cefixime, the ET was interrupted and the fluorescent signal was recovered. Results/Conclusions This method showed high sensitivity and an impressively low detection limit of 169 nM. Highlights This low-cost, simple strategy for cefixime detection exhibits excellent stability, selectivity, and sensitivity. Moreover, it was successfully applied for the detection of cefixime in tablets and in a complex biological environment, confirming its great potential utility for drug analysis, biological process research, and clinical research.

scholarly journals Green Preparation of Fluorescent Carbon Quantum Dots from Cyanobacteria for Biological Imaging

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 616 ◽  
Author(s):  
Xi Wang ◽  
Pei Yang ◽  
Qian Feng ◽  
Taotao Meng ◽  
Jing Wei ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Carbon Source ◽  
Large Scale ◽  
Low Cost ◽  
Average Diameter ◽  
Carbon Quantum Dots ◽  
Water Soluble ◽  
High Concentration ◽  
Wide Range ◽  
Low Cytotoxicity

Biomass-based carbon quantum dots (CQDs) have become a significant carbon materials by their virtues of being cost-effective, easy to fabricate and low in environmental impact. However, there are few reports regarding using cyanobacteria as a carbon source for the synthesis of fluorescent CQDs. In this study, the low-cost biomass of cyanobacteria was used as the sole carbon source to synthesize water-soluble CQDs by a simple hydrothermal method. The synthesized CQDs were mono-dispersed with an average diameter of 2.48 nm and exhibited excitation-dependent emission performance with a quantum yield of 9.24%. Furthermore, the cyanobacteria-derived CQDs had almost no photobleaching under long-time UV irradiation, and exhibited high photostability in the solutions with a wide range of pH and salinity. Since no chemical reagent was involved in the synthesis of CQDs, the as-prepared CQDs were confirmed to have low cytotoxicity for PC12 cells even at a high concentration. Additionally, the CQDs could be efficiently taken up by cells to illuminate the whole cell and create a clear distinction between cytoplasm and nucleus. The combined advantages of green synthesis, cost-effectiveness and low cytotoxicity make synthesized CQDs a significant carbon source and broaden the application of cyanobacteria and provide an economical route to fabricate CQDs on a large scale.

scholarly journals An Alternative Route to Obtain Carbon Quantum Dots from Photoluminescent Materials in Peat

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1492 ◽  
Author(s):  
Rafael Souza da Costa ◽  
Wiliam Ferreira da Cunha ◽  
Nizamara Simenremis Pereira ◽  
Artemis Marti Ceschin
Keyword(s):  
Quantum Dots ◽  
Aromatic Compounds ◽  
Elemental Carbon ◽  
Low Cost ◽  
Carbon Quantum Dots ◽  
Raw Material ◽  
Transmission Electron ◽  
Photoluminescent Materials ◽  
Average Size ◽  
Green Coloration

Peat, an organic compound easily found in the soil (easy to acquire), has more than 50% elemental carbon in its composition and can be used as raw material to produce carbon quantum dots (CQDs, C-dots, Carbon Dots). In this work we describe two simple and low-cost routes for the acquisition of these photoluminescent materials based on peat. The final products were characterized by Fourier transform infrared spectroscopy (FTIR), absorption (UV-Vis) and emission (PL) spectra and high-resolution transmission electron microscopy (HRTEM). The produced CQDs have an average size of 3.5 nm and exhibit coloration between blue and green. In addition, it is possible to produce photoluminescence by means of the aromatic compounds also present in the composition of the peat, in turn exhibiting an intense green coloration. The results indicate great versatility of peat for the production of photoluminescent materials.

scholarly journals Facile and High-yield Synthesis of N-doped Carbon Quantum Dots from Biomass Quinoa Saponin for the Detection of Co2+

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Cuo Zhou ◽  
Shunwei Wu ◽  
Shenghui Qi ◽  
Weijun Song ◽  
Chunyan Sun
Keyword(s):  
Quantum Dots ◽  
Metal Ion ◽  
Light Emission ◽  
Low Cost ◽  
Carbon Quantum Dots ◽  
High Yield ◽  
Excitation Wavelength ◽  
Uniform Size ◽  
Orthogonal Experiments ◽  
Co2 Detection

Hydrothermal synthesis of carbon quantum dots (CQDs) from natural biomass is a green and sustainable route for CQDs applications in various fields. In this work, the preparation and characterization of CQDs based on quinoa saponin were investigated. The optimum synthetic conditions determined by orthogonal experiments were as follows: 2 g quinoa saponin powder and 0.04 mol ethylenediamine reacted at 200°C for 10 h. The relative fluorescence quantum yield (QY = 22.2%) can be obtained, which is higher than some results reported in the literatures. The prepared CQDs had a small and uniform size (∼2.25 nm) and exhibited excitation wavelength-dependent blue light emission behavior. The CQDs displayed excellent sensitivity for Co2+ detection along with good linear correlation ranging from 20 to 150 µM and the detection limit of 0.49 µM. The CQDs prepared in this experiment were successfully implanted into soybean sprouts for fluorescence imaging. The sprouts could grow healthily even soaked in the CQDs solution for two weeks, demonstrating the low toxicity of the CQDs. The advantages of the CQDs, such as low cost, ease of manufacture, nontoxicity, and stability, have potential applications in many areas such as metal ion detection and biosensing.

scholarly journals P-Doped Carbon Quantum Dots with Antibacterial Activity

Micromachines ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1116
Author(s):  
Shuiqin Chai ◽  
Lijia Zhou ◽  
Shuchen Pei ◽  
Zhiyuan Zhu ◽  
Bin Chen
Keyword(s):  
Quantum Dots ◽  
Antibacterial Activity ◽  
Bacterial Infections ◽  
Fluorescence Emission ◽  
Carbon Quantum Dots ◽  
Microbial Pathogens ◽  
Electronic Interaction ◽  
Minimal Inhibitory Concentrations ◽  
E Coli ◽  
Zeta Potential Analysis

It is a major challenge to effectively inhibit microbial pathogens in the treatment of infectious diseases. Research on the application of nanomaterials as antibacterial agents has evidenced their great potential for the remedy of infectious disease. Among these nanomaterials, carbon quantum dots (CQDs) have attracted much attention owing to their unique optical properties and high biosafety. In this work, P-doped CQDs were prepared by simple hydrothermal treatment of m-aminophenol and phosphoric acid with fluorescence emission at 501 nm when excited at 429 nm. The P-doped CQDs showed effective antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The minimal inhibitory concentrations (MICs) of P-doped CQD were 1.23 mg/mL for E. coli and 1.44 mg/mL for S. aureus. Furthermore, the morphologies of E. coli cells were damaged and S. aureus became irregular when treated with the P-doped CQDs. The results of zeta potential analysis demonstrated that the P-doped CQDs inhibit antibacterial activity and destroy the structure of bacteria by electronic interaction. In combination, the results of this study indicate that the as-prepared P-doped CQDs can be a promising candidate for the treatment of bacterial infections.

scholarly journals Environment-dependent Emission Tuning in the Multicolor Nitrogen-doped Carbon Quantum Dots

2021 ◽  
Author(s):  
Dineshkumar Sengottuvelu ◽  
Abdul Kalam Shaik ◽  
Satish Mishra ◽  
Mahsa Abbaszadeh ◽  
Nathan Hammer ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Solid State ◽  
Large Scale ◽  
Low Cost ◽  
Visible Region ◽  
Carbon Quantum Dots ◽  
One Pot ◽  
Nitrogen Doped ◽  
Emission Changes ◽  
Nitrogen Doped Carbon

Carbon quantum dots (CQDs) are fascinating luminous materials from the carbonaceous family and are increasingly being investigated in many optoelectronic applications due to their unique photoluminescence (PL) characteristics. Herein, we report the synthesis of nitrogen-doped carbon quantum dots (NCQDs) from citric acid and m-phenylenediamine using a one-pot hydrothermal approach. The environment-dependent emission changes of NCQDs were extensively investigated in various solvents, in solid-state, and in physically assembled PMMA-PnBA-PMMA copolymer gels in 2-ethyl hexanol. The NCQDs display bright emission in various solvents as well as in solid-state and a temperature-dependent enhanced emission in gels. In detail, these NCQDs exhibit multicolor PL emission across the visible region and its enhancement upon changing the environment (solutions and polymer matrices). The NCQDs also exhibit excitation-dependent PL and solvatochromism, which are rarely observed in CQDs. Most CQDs are non-emissive in the aggregated or solid-state due to the aggregation-caused quenching (ACQ) effect, limiting their solid-state applications. However, these NCQDs display a strong solid-state emission centered at 568 nm ascribed to the presence of abundant surface functional groups, which helps to prevent the - interaction between the NCQDs and to overcome the ACQ effect in the solid-state. Interestingly, the NCQD containing gels display a significant fluorescence enhancement than the NCQDs in 2-ethyl hexanol solution because of the interaction between the polar PMMA blocks and NCQDs. This research opens up the development of large-scale, low-cost multicolor phosphor for the fabrication of optoelectronic devices, sensing, and bioimaging applications.

Highly Fluorescent N-Doped Carbon Quantum Dots Derived from Bamboo Stems for Selective Detection of Fe3+ Ions in Biological Systems

2021 ◽  
Vol 17 (2) ◽  
pp. 312-321
Author(s):  
Jiamin Yan ◽  
Yuneng Lu ◽  
Shaowen Xie ◽  
Haihu Tan ◽  
Weilan Tan ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Biological Systems ◽  
High Sensitivity ◽  
Carbon Quantum Dots ◽  
Clinical Diagnostics ◽  
Quenching Effect ◽  
Biologically Relevant ◽  
Sensing Platform ◽  
Wide Ph Range ◽  
High Fluorescence

The establishment of sensing platform for trace analysis of Fe3+ in biological systems is meaningful for health monitoring. Herein, a Fe3+ sensitive fluorescent nanoprobe was constructed based on highly fluorescent N-doped carbon quantum dots (NCQDs) derived from bamboo stems through a hydrothermal method employing ethylenediamine as the nitrogen dopant. The prepared NCQDs had a uniformly distributed size and their mean size was around 2.43 nm. Abundant functional groups (C=N, N-H, C=O, and carboxyl) anchored on NCQDs demonstrated successful doping of N in CQDs. The obtained NCQDs possessed a high fluorescence quantum yield of 20.02% and outstanding fluorescence stability over a wide pH range and at high ionic strengths. Moreover, Fe3+ ions presented a specific fluorescent quenching effect to the as-prepared NCQDs. The calibration curve for fluorescence quenching degree corresponding to Fe3+ concentration showed a linear response in a range of 0.01–10 µM, and detection limit was 0.486 µM, which indicated that the NCQDs had high sensitivity to Fe3+ ions. Ascribed to these unique properties, the NCQDs were selected as luminescent probes for trace amount of Fe3+ ions in human serum. These results demonstrated their promising use in clinical diagnostics and other biologically relevant studies.

Biological Activity Test of Dendrobium Huoshanense and Its Application in the Detection of Environmental Pollutant Phenols

2021 ◽  
Vol 13 (7) ◽  
pp. 1205-1214
Author(s):  
Yujuan Wang ◽  
Jun Dai ◽  
Peipei Wei ◽  
Yongping Cai ◽  
Bangxing Han
Keyword(s):  
Quantum Dots ◽  
Hydrothermal Reaction ◽  
High Sensitivity ◽  
Carbon Quantum Dots ◽  
Environmental Pollutant ◽  
One Step ◽  
New Type ◽  
Filtration Effect ◽  
Dendrobium Huoshanense

ABSTRACTIn this research, a new type of carbon quantum dot was prepared from Dendrobium huoshanense via one-step hydrothermal reaction at 200 °C for 6 h. The as-derived carbon quantum dots exhibited good fluorescence properties, with quantum yield of 23.57%. The extraction and determination of Dendrobium huoshanense enzymes activity were performed for different incubation times to study the theoretical reference for the dynamic changes of the main enzyme activity in the process of Dendrobium huoshanense growth and the solid processing industry. The results demonstrated that Dendrobium huoshanense was a low toxic carbon source material. Moreover, the prepared carbon quantum dots exhibited high sensitivity for the detection of nonylphenol, allowing a range of linear response of 0.5–50 µM (R2 = 0.9997). The detection limit was a slow as 95.32 nM. These results indicated that fluorescence internal filtration effect influenced nonylphenol-induced quenching of the Dendrobium huoshanense-carbon quantum dots fluorescence. The Dendrobium huoshanense-carbon quantum dots were successfully used to track nonylphenol in environmental samples. Therefore, their exploitation offers a promising approach for environmental pollutant detection.

Quantitative Determination of Triglyceride by Photoactivated CdSe/ZnS Quantum Dots Through Fluorescence Assay

2008 ◽  
Vol 8 (7) ◽  
pp. 3434-3438 ◽  
Author(s):  
Chin-Ping Huang ◽  
Yaw-Kuen Li ◽  
Teng-Ming Chen
Keyword(s):  
Quantum Dots ◽  
Color Change ◽  
Low Cost ◽  
High Sensitivity ◽  
Assay System ◽  
Oil Refining ◽  
Quantitative Detection ◽  
Multiple Reactions ◽  
High Flexibility

The quantitative detection of triglycerides is an important issue for health inspection of metabolic disorders and for food and oil-refining industries. Many methods have been designed to approach this target, in which multiple reactions catalyzed by enzymes are normally coupled consecutively. In this study, we demonstrated a simple assay system containing lipase and photoactivated luminescent CdSe/ZnS quantum dots (QDs) for the quantitative detection of triglycerides. Photoactivated CdSe/ZnS QDs function as a sensitive "indicator" to reveal the minute acidity change of the assay system resulting from the enzymatic hydrolysis of triglycerides. By controlling the initial buffer condition of the assay system at 5, 10, or 20 mM phosphate buffer at pH 8.0, respectively, the quenching ratio of the QDs fluorescence intensity monitored at the maximum photoluminescence showed a linear correlation with the concentration of the examined triglyceride in the range of 0.02–6, 0.2–10, or 2–20 mM, respectively. The assay system also provides a convenient way to estimate triglyceride concentration by visualizing the color change of the QDs fluorescence. As compared to most of the existing methods, the system reported herein possessed many advantages, including simplicity, low cost, high flexibility, and high sensitivity. Furthermore, no complicated chemical modification or enzyme immobilization is needed.

Sign in / Sign up

Export Citation Format

Share Document