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- 2018
- metal object detection (MOD)
- wireless power transfer (WPT)
- auxiliary detection coil
- Chest X-ray (CXR)
- Computer-aided Diagnosis (CADx)
- Early detection of tuberculosis
- Electrical Engineering and Automation
- Optoelectronic Information Science and Engineering
- Shanghai Jiao Tong University
- Bandung Institute of Technology (ITB)
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Opposite changing dual-emission luminescence of gold nanoparticles by sulfhydryl to develop a pesticide biosensing strategy
摘要： As the merit of ratiometric assay is impregnable due to potentially interfering processes, a ratiometric method for pesticide detection was developed. By adjusting glutathione : HAuCl4 to an appropriate ratio, dual-emission luminescent ultra-small gold nanoparticles (AuNPs) with a high emission at 800 nm and a low emission at 600 nm were synthesized. Interestingly, the sulfhydryl-containing compounds were found to result in completely opposite changes to strengthen the 600 nm emission and weaken the 800 nm emission. Therefore, dual-emitted AuNPs were engaged to develop a ratiometric pesticide biosensing strategy. In the presence of acetylcholinesterase (AChE), acetylthiocholine can be hydrolyzed into thiocholine, whose newly generated sulfhydryl can interact with AuNPs, resulting in the opposite change of the dual emissions. While adding pesticide as an AChE inhibitor, the catalytic activity of AChE is inhibited and less thiocholine was produced. The biosensing system shows an obvious sensitivity to the pesticide with a limit of detection (LOD) of 0.2 nM for aldicarb and 0.07 nM for chlorpyrifos. Therefore, this simple assay is suitable for AChE activity and pesticide detection, even in vegetable samples.
关键词： sulfhydryl,ratiometric assay,gold nanoparticles,AChE activity,biosensing,pesticide detection
更新于2025-11-19 16:56:35
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Detection of Tetracycline in Water Using Glutathione-protected Fluorescent Gold Nanoclusters
摘要： Tetracycline (Tc), a widely used antibiotic, is one of the major pollutants in water. Herein, glutathione (GSH)-protected Au nanoclusters (GSH-AuNCs) were prepared to detect Tc. The fluorescence quenching ratio of GSH-AuNCs shows an excellent linear response against tetracycline in the concentration range of 50 μg/L – 50 mg/L with the detection limit of 5.31 μg/L. For the test paper prepared by GSH-AuNCs, 1 mg/L Tc caused a significant difference that could be recognized by the naked eye. The method exhibited good selectivity and excellent recovery when applied to a tap water sample. The method has the potential for Tc detection in real samples.
关键词： tetracycline detection,Au nanocluster,glutathione,recovery experiment,quenching ratio
更新于2025-11-19 16:56:35
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A new multi-analyte fluorogenic sensor for efficient detection of Al <sup>3+</sup> and Zn <sup>2+</sup> ions based on ESIPT and CHEF features
摘要： The fluorogenic chemosensor 3-(((2-hydroxy-4-methylphenyl)imino)methyl)-[1,10-biphenyl]-4-ol (H2L) efficiently detects Zn2+ and Al3+ ions and subsequently fluoride ion in methanol–water (4/1, v/v, pH = 7.2) solution. The probe itself is non-emissive but upon treatment with Al3+ and Zn2+, it exhibits high fluorescence emission at two different wavelengths of 546 nm and 529 nm, respectively. Both excited-state intramolecular proton transfer (ESIPT) and chelation enhanced fluorescence (CHEF) processes play important roles in the enhancement of fluorescence intensity. Chelation of Zn2+ and Al3+ with the probe (H2L) inhibits CQN isomerization and ESIPT which consequently enhances the emission intensity. The emission intensity of H2L–Al3+ is selectively quenched upon titration with F- anions. The structure of the probe is confirmed by the single crystal X-ray diffraction method. The electronic structure and sensing mechanism of the probe (H2L) are supported by density functional theory (DFT) and time-dependent density functional theory (TDDFT).
关键词： Zn2+ detection,fluoride detection,CHEF,fluorogenic sensor,ESIPT,Al3+ detection
更新于2025-11-19 16:46:39
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The Application of Green-Synthesis-Derived Carbon Quantum Dots to Bioimaging and the Analysis of Mercury(II)
摘要： Ginkgo leaves were used as precursors for the hydrothermal synthesis of carbon quantum dots (CQDs), which were subsequently characterized by transmission electron microscopy as well as Fourier-transform infrared, X-ray powder di?raction, and X-ray photoelectron spectroscopy. The prepared CQDs exhibited a ?uorescence quantum yield of 11% and superior water solubility and ?uorescence stability, as well as low cytotoxicities and excellent biocompatibilities with A549 and HeLa cells; these CQDs were also used to bioimage HeLa cells. Moreover, owing to the experimental observation that Hg2+ quenches the ?uorescence of the CQDs in a speci?c and sensitive manner, we developed a method for the detection of Hg2+ using this ?uorescence sensor. The sensor exhibited a linear range for Hg2+ of 0.50–20 μM, with an excellent coe?cient of determination (R2 ? 0.9966) and limit of detection (12.4 nM). In practice, the proposed method was shown to be highly selective and sensitive for the monitoring of Hg2+ in lake water and serum samples.
关键词： mercury(II) detection,carbon quantum dots,hydrothermal synthesis,fluorescence quenching,bioimaging
更新于2025-11-19 16:46:39
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A novel fluorescent probe for H2O2 detection based on CdSe@ZnS quantum dots/Ag nanocluster hybrid
摘要： The selective and quantitative detection of H2O2 is important for its employment in physiological, environmental and industrial applications. In this paper, a sensitive and selective strategy for H2O2 detection was established based on the fluorescence quenching of CdSe@ZnS quantum dots (QDs) by H2O2-mediated etching process of Ag nanoclusters (AgNCs). In this strategy, dihydrolipoic acid (DHLA) modified AgNCs were applied as H2O2 response group, the existence of H2O2 could initiate the oxidation of AgNCs and the production of Ag+, which could give rise to the effective fluorescence quenching of CdSe@ZnS QDs. Based on this strategy, the present fluorescent assay could realize the quantificational detection of H2O2 and the limit of detection is calculated to be 0.3 mM under the optimum conditions. Furthermore, CdSe@ZnS/AgNCs hybrid-based probe was applied to detecting H2O2 in milk samples and showed a good recoveries results ranged from 95.8% to 112.0%, meaning the potential applicability of this strategy.
关键词： H2O2 detection,Ag nanoclusters,Fluorescence quenching,CdSe@ZnS quantum dots
更新于2025-11-19 16:46:39
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Aqueous synthesis of glutathione-capped CuInS2/ZnS quantum dots-graphene oxide nanocomposite as fluorescence a??switch OFFa?? for explosive detection
摘要： This work reports a simple and fast aqueous preparation of CuInS2/ZnS-graphene oxide (CIS/ZnS-GO) nanocomposite as a fluorescence "switch OFF" probe for the fluorescence detection of 2, 4, 6-trinitrophenol (TNP.) – a raw material for various explosive devices. The as-synthesized nanocomposites was characterised using Ultraviolet–visible (UV–Vis) spectroscopy, photoluminescence (PL) spectroscopy, high resolution transmission electron microscopy (HR-TEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and Raman scattering. The PL studies revealed that the adsorption of TNP onto GO via p-p stacking enhanced the charges transfer from CuInS2/ZnS-GO to the analyte. The limit of detection (LOD) for the analyte is 57 lΜ.
关键词： Nanocomposite,Explosive,Quenching,Trinitrophenol,Fluorescence,Detection
更新于2025-11-19 16:46:39
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Highly Photoluminescent and Stable N-Doped Carbon Dots as Nanoprobes for Hg2+ Detection
摘要： We developed a microreactor with porous copper fibers for synthesizing nitrogen-doped carbon dots (N-CDs) with a high stability and photoluminescence (PL) quantum yield (QY). By optimizing synthesis conditions, including the reaction temperature, flow rate, ethylenediamine dosage, and porosity of copper fibers, the N-CDs with a high PL QY of 73% were achieved. The PL QY of N-CDs was two times higher with copper fibers than without. The interrelations between the copper fibers with different porosities and the N-CDs were investigated using X-ray photoelectron spectroscopy (XPS) and Fourier Transform infrared spectroscopy (FTIR). The results demonstrate that the elemental contents and surface functional groups of N-CDs are significantly influenced by the porosity of copper fibers. The N-CDs can be used to effectively and selectively detect Hg2+ ions with a good linear response in the 0~50 μM Hg2+ ions concentration range, and the lowest limit of detection (LOD) is 2.54 nM, suggesting that the N-CDs have great potential for applications in the fields of environmental and hazard detection. Further studies reveal that the different d orbital energy levels of Hg2+ compared to those of other metal ions can affect the efficiency of electron transfer and thereby result in their different response in fluorescence quenching towards N-CDs.
关键词： carbon dots,microreactor,Hg2+ detection,porous copper fibers
更新于2025-11-19 16:46:39
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A Label-Free Fluorescent DNA Calculator Based on Gold Nanoparticles for Sensitive Detection of ATP
摘要： Herein we described a deoxyribonucleic acid (DNA) calculator for sensitive detection of the determination of adenosine triphosphate (ATP) using gold nanoparticles (GNP) and PicoGreen fluorescence dye as signal transducer, and ATP and single-stranded DNA (DNA-M') as activators. The calculator-related performances including linearity, reaction time, logic gate, and selectivity were investigated, respectively. The results revealed that this oligonucleotide sensor was highly sensitive and selective. The detection range was 50–500 nmol/L (R2 = 0.99391) and the detection limit was 46.5 nmol/L. The AND DNA calculator was successfully used for the ATP detection in human urine. Compared with other methods, this DNA calculator has the characteristics of being label-free, non-enzymic, simple, and highly sensitive.
关键词： DNA calculator,enzyme-free,gold nanoparticles,label-free fluorescence,ATP detection
更新于2025-11-19 16:46:39
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A Label-Free Fluorescent DNA Machine for Sensitive Cyclic Amplification Detection of ATP
摘要： In this study, a target recycled ampli?cation, background signal suppression, label-free ?uorescent, enzyme-free deoxyribonucleic acid (DNA) machine was developed for the detection of adenosine triphosphate (ATP) in human urine. ATP and DNA fuel strands (FS) were found to trigger the operation of the DNA machine and lead to the cyclic multiplexing of ATP and the release of single stranded (SS) DNA. Double-stranded DNA (dsDNA) was formed on graphene oxide (GO) from the combination of SS DNA and complementary strands (CS(cid:48)). These double strands then detached from the surface of the GO and in the process interacted with PicoGreen dye resulting in amplifying ?uorescence intensity. The results revealed that the detection range of the DNA machine is from 100 to 600 nM (R2 = 0.99108) with a limit of detection (LOD) of 127.9 pM. A DNA machine circuit and AND-NOT-AND-OR logic gates were successfully constructed, and the strategy was used to detect ATP in human urine. With the advantage of target recycling ampli?cation and GO suppressing background signal without ?uorescent label and enzyme, this developed strategy has great potential for sensitive detection of different proteins and small molecules.
关键词： cyclic ampli?cation,ATP detection,DNA machine,label-free ?uorescence,graphene oxide,logic gate
更新于2025-11-19 16:46:39
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A “turn-on” fluorometric assay for kanamycin detection by using silver nanoclusters and surface plasmon enhanced energy transfer
摘要： A rapid method is described for the determination of the antibiotic kanamycin. It integrates a kanamycin-binding aptamer and surface plasmon enhanced energy transfer (SPEET) between DNA-templated silver nanoclusters (AgNCs) and gold nanoparticles (AuNPs). The AgNCs and AuNPs were selected as energy donor and energy acceptor, respectively. The aptamer was designed to regulate the energy transfer between AgNCs and AuNPs. The aptamer was adsorbed on the AuNPs. Upon addition of kanamycin, the aptamer-kanamycin complex is formed, and this results in the aggregation of the AuNPs in high salt concentration, the formation of a blue coloration, and in the suppression of the SPEET process. The fluorescence of the AgNCs (with excitation/emission peaks at 560/600 nm) is quenched by the aptamer protected AuNPs in absence of kanamycin. The fluorescence on addition of kanamycin increases linearly in the 5 to 50 nM concentration range, with a lower detection limit of 1.0 nM (at S/N = 3). The assay can be performed within 30 min. It was successfully applied to the determination of kanamycin in spiked milk samples, and recoveries ranged between 90.2 and 95.4%. Conceivably, the strategy has a wide potential for screening by simply changing the aptamer.
关键词： Ag NCs,Milk analysis,Antibiotics detection,Au NPs,Food safety,Aptasensor
更新于2025-11-19 16:46:39