FOOD CHEMISTRY
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2024
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IF 8.5
Wei Lan,Yanmin Rao,Xiangyu Zhao,Yi Zhao,Xinyi Min,Yue Wu,Ziyi Jiang,Ting Li,Yinhua Li,Hengye Chen,Wanjun Long,Yuanbin She,Haiyan Fu
Acid-sensitive CdTe quantum dots-loaded alginate hydrogel (CdTe QDs-AH) beads were designed for the visual detection of SO 2 residues. As proof of concept, two types of CdTe QDs were selected as model probes and embedded in AH beads. The entire test was performed within 25 min in a modified double-layer test tube with one bead fixed above the sample solution. Adding citric acid and heating at 70 ℃ for 20 min transformed the sulfites in the solution into SO 2 gas, which then quenched the fluorescence of the CdTe QDs-AH beads. Using this assay, qualitative, naked-eye detection of SO 2 residues was achieved in the concentration range of 25–300 ppm, as well as precise quantification was possible based on the difference in the average fluorescence brightness of the beads before and after the reaction. Five food types were successfully analysed using this method, which is simpler and more economical than existing methods, and does not require complex pretreatment.
研究领域:
食品科学
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分析化学
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纳米技术
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产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2018
·Vol. 42
·期 19
·15743-15749
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IF 3.201
Jing Wang,Daquan Li,Xinyue Liu,Yu Qiu,Xiao Peng,Liang Huang,Huimin Wen,Jun Hu
Aqueous N-acetyl-L-cysteine (NAC)-capped CdTe quantum dots (QDs) are prepared in one step by using sodium tellurite as a tellurium source and sodium borohydride as a reductant. The fluorescence (FL) emissions of the QDs are tunable between 514 and 753 nm. The effects of NAC/Cd, Cd/Te molar ratios, and pH values on the photoluminescence quantum yield (PLQY) of the QDs have been systematically studied. They display a high PLQY of up to 52.83%, with uniform narrow-size distributions. Furthermore, the obtained green- and red-emissive CdTe QDs are applied to explore the impact of QD size on the FL response toward glutathione (GSH) by a “turn-on” strategy. The results imply that the large-sized CdTe QDs with red FL are more suitable for detecting GSH than the small-sized QDs with green FL. The possible mechanism is also investigated.
研究领域:
材料科学
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生物化学
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
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2020
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IF 6.306
Yuning Yang,Wei Liu,Jie Cao,Yiwei Wu
A ratiometric sensor of MOF/ CdTe QDs was constructed by physically mixing CdTe QDs ( λ em = 605 nm) with MOF (Fe-MIL-88NH 2, λ em = 425 nm). Under an UV lamp ( λ ex = 365 nm), orange-red CdTe QDs is gradually quenched with increasing levels of Hg 2+ or Cu 2+ , while blue MOF is unchanged, accompanying with a visual change from bright pink to blue fluorescence. Hence, a new method for determining Hg 2+ and Cu 2+ by MOF/CdTe QDs sensor is established, whose detection limits are 0.22 ng mL −1 for Hg 2+ (2.1% RSD) and 0.26 ng mL −1 for Cu 2+ (1.1% RSD), respectively. In addition, on-site, rapid and visual determination of Hg 2+ /Cu 2+ in red wine without any pretreatment is realized by using a MOF/CdTe QDs paper-based sensor. For Hg 2+ and Cu 2+ , the semi-quantitative detection ranges of the paper-based sensor are both 10 ~ 5000 ng mL −1 , implying that it has great application value in analyzing Hg 2+ and Cu 2+ in liquid samples.
研究领域:
分析化学
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材料科学
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环境科学
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产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 12
·1-10
·
IF 6.232
Wang Zhao,Li Shuting,Zhou Chunyan,Sun Yingying,Pang Hui,Liu Wei,Li Xinchun
A sensitive and robust fluorescent assay of 6-MP is described which relies on the facile assembly of a fluorescence nanoprobe by design of silica nanosphere encapsulated CdTe quantum dots (CdTe QDs) as scaffold, coupling with chemically tethered folic acid (FA)–protected silver nanoparticles (AgNPs) that function as responsive element. In this way a stable ternary core-shell-satellite nanostructure with dual-emission signals can be established. On binding to the target molecules, 6-MP, FA molecules initially occupied by AgNPs are liberated to give dose-dependent fluorescence emission, which can further form a self-calibration ratiometric fluorescence assay using CdTe QDs as an internal reference. The nanoprobe color vividly changes from red to blue, enabling the direct visual detection. The linear concentration range is 0.15~50 μM with the detection limit of 67 nM. By virtue of the favorable selectivity and robust assays, the nanoprobe was applied to 6-MP detection in urine samples, with recoveries from 97.3 to 106% and relative standard deviations (RSD) less than 5%.
Graphical abstract
研究领域:
分析化学
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生物医学工程
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纳米技术
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DOI
PubMed
高影响因子
JOURNAL OF THE CHINESE CHEMICAL SOCIETY
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2023
·Vol. 70
·期 10
·1893-1900
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IF 1.8
Qing Huang,Chen-dong Ling,Wen-feng Zhuge,Zeng-hu Zhang,Gang Xiang,Jin-yun Peng,Xue Liang
Objective Para-aminophenol (PAP) is a critical intermediate widely used in medicine, pharmaceutical, rubber, antioxidant, petroleum, and other fields, but it is harmful to the environment. A novel photo electrochemical (PEC) sensor was synthesized and applied to detect PAP based on the composite material of cadmium telluride nanoparticle (CdTe NPs)–decorated copper–tetramine phthalocyanine covalently grafted graphene oxide (CuTAPc-Gr). Materials & Methods Copper–tetramine phthalocyanine (CuTAPc) has an excellent PEC conversion effect and narrow band. Graphene (Gr) has high mechanical stability and suitable bandgap. CuTAPc-Gr was synthesized by chemical covalent bonding. And CdTe NPs@CuTAPc-Gr composite was prepared by ultrasonic mixing method using CuTAPc-Gr and CdTe NPs. The morphology and structure of the PEC materials were characterized using scanning electron microscopy and fourier transform infrared spectrometer. PAP contents were evaluated by the Time-Current method. And the electron transfer rate of the PEC sensor was studied by electrochemical impedance spectroscopy methods. Results & Discussion CdTe NPs@CuTAPc-Gr has excellent PEC properties. In the PAP analysis, distinct regular changes in the photocurrent within a linear range of 33.3–1330.0 nM were noted. The limit of detection was 15.5 nM. Acetaminophen, phloroglucin, and other substances did not affect PAP content determination. The water samples were analyzed using the proposed PEC sensor. The results show that the recoveries were in the range of 97.85%–99.58%, and relative standard deviations (RSDs) were less than 2%. Conclusions The PEC sensor exhibited excellent sensitivity, selectivity, and stability. The proposed method provides an effective strategy for constructing PEC sensors to detect PAP in water samples and a promising PEC platform for analyzing other small molecules.
研究领域:
分析化学
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环境科学
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材料科学
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产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2017
·
IF 5.401
Fanping Shi,Lei Wang,Yan Li,Yu Zhang,Xingguang Su
In this work, we designed a simple, convenient and high sensitive “turn-on” fluorescence platform for trypsin assay based on N -acetyl- l -cysteine capped CdTe Quantum Dots (NAC-CdTe QDs). A series of NAC-CdTe QDs with different sizes were synthesized in aqueous via refluxing routes. The fluorescence of NAC-CdTe QDs could be effectively quenched by hemoglobin (Hb) via the electron transfer interactions from NAC-CdTe QDs to hemoglobin due to the electrostatic attraction of QDs/Hb complex. In the presence of trypsin, hemoglobin would be hydrolyzed to small peptides, releasing inactive hemin molecules.Hemin has slight effect on the fluorescent intensity of NAC-CdTe QDs, so the combination of hemoglobin and NAC-CdTe QDs would be dissociated, leading to the fluorescence recovery of NAC-CdTe QDs. Therefore, we could monitor the trypsin activity by utilizing the different fluoresence responses of NAC-CdTe QDs to hemoglobin and hemin. The recovered fluorescence intensity of NAC-CdTe QDs was proportional to the logarithm of trypsin concentration in the range of 0.05–10 mU mL −1 and the detection limit for trypsin was 0.036 mU mL −1 . A model for trypsin inhibition was further established to verify the feasibility of the system. The IC 50 value is 3.06 μg mL −1 for the inhibitor from soybean. Thus, a label free real time fluorometric assay for trypsin and inhibitor screening has been developed. The established method showed a high selectivity and sensitivity for trypsin over other biological relevant enzyme, and it was applied to the determination of trypsin in human urine sample with satisfactory results.
研究领域:
生物化学
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医学诊断
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纳米技术
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产品关联
DOI
高影响因子
PHOTOCHEMISTRY AND PHOTOBIOLOGY
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2020
·Vol. 96
·期 5
·1154-1160
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IF 2.721
Kaili He,Xin Zhan,Lian Liu,Xiaohong Ruan,Yiwei Wu
A simple and effective ratiometric fluorescence sensor of CdTe QDs/GCNNs for on-site and rapid analysis of Cu 2+ has been established by mixing physically CdTe QDs and graphite carbon nitride (GCNNs). Two emissions peaks of CdTe QDs at 572 nm and GCNNs at 436 nm are both excitated at 340 nm. Under a UV lamp, fluorescent of traffic yellow CdTe QDs is linearly quenched by Cu 2+ (as the detection signal), while blue GCNNs remains unchanged (as the reference), resulting in a distinguishable color change gradually from pink yellow to blue. The limit of detection (LOD) of this new sensor for Cu 2+ is as low as 0.47 ng mL −1 with 1.4 % RSD. The established method has been successfully applied to detection of Cu 2+ in various drinks with satisfactory results. Moreover, a paper-based sensor, which has been prepared by soaking cellulose acetate membrane in CdTe QDs/GCNNs sensor solution, has a wide semiquantitative detection range for Cu 2+ (0.01 ~ 5.0 μg mL −1 ). It has realized successfully on-site and rapid determination of Cu 2+ in red wine without any pretreatment procedure and is of great promotion and application value in determination of Cu 2+ in liquid samples.
研究领域:
分析化学
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环境科学
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食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2014
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IF 2.871
Chen Zhang,Shichao Xu,Xueping Zhang,Dandan Huang,Runlan Li,Shihuai Zhao,Bing Wang
In this article, we developed an electrochemical method for detection of specific DNA sequences of bladder cancer cells based on CdTe quantum dots (QDs) modified glassy carbon electrode (GCE). Methylene blue (MB) was intercalated into the hybridized double stranded DNA (dsDNA) and used as electrochemical indictor. CdTe QDs amplified the electrochemical signals due to their larger surface area, which can immobilize more single stranded DNA (ssDNA) probes on electrode surface. The morphology and optical properties of CdTe QDs were characterized by transmission electron microscope (TEM), X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), fluorescence spectra (FS), UV–vis spectrum and Fourier transform infrared spectrum (FTIR). Moreover, target DNA was detected by differential pulse voltammetry (DPV) quantitatively. The linear range was obtained from 1 × 10 −12 M to 1 × 10 −8 M, and the limit of detection was 6.435 × 10 −13 M (3δ). The control experiments were also carried out by hybridization with various mismatched DNA sequences. These results displayed this fabricated electrochemical DNA biosensor was of good selectivity, sensitivity, stability and easy operation.
研究领域:
生物化学
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电化学
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癌症研究
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2012
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IF 2.823
Feng Gao,Qingqing Ye,Peng Cui,Lu Zhang
We here report an efficient and enhanced fluorescence energy transfer system between confined quantum dots (QDs) by entrapping CdTe into the mesoporous silica shell (CdTe@SiO2) as donors and gold nanoparticles (AuNPs) as acceptors. At pH 6.50, the CdTe@SiO2–AuNPs assemblies coalesce to form larger clusters due to charge neutralization, leading to the fluorescence quenching of CdTe@SiO2 as a result of energy transfer. As compared with the energy transfer system between unconfined CdTe and AuNPs, the maximum fluorescence quenching efficiency of the proposed system is improved by about 27.0%, and the quenching constant, Ksv, is increased by about 2.4-fold. The enhanced quenching effect largely turns off the fluorescence of CdTe@SiO2 and provides an optimal “off-state” for sensitive “turn-on” assay. In the present study, upon addition of melamine, the weak fluorescence system of CdTe@SiO2–AuNPs is enhanced due to the strong interactions between the amino group of melamine and the gold nanoparticles via covalent bond, leading to the release of AuNPs from the surfaces of CdTe@SiO2; thus, its fluorescence is restored. A “turn-on” fluorimetric method for the detection of melamine is proposed based on the restored fluorescence of the system. Under the optimal conditions, the fluorescence enhanced efficiency shows a linear function against the melamine concentrations ranging from 7.5 × 10–9 to 3.5 × 10–7 M (i.e., 1.0–44 ppb). The analytical sensitivity is improved by about 50%, and the detection limit is decreased by 5.0-fold, as compared with the analytical results using the CdTe–AuNPs system. Moreover, the proposed method was successfully applied to the determination of melamine in real samples with excellent recoveries in the range from 97.4 to 104.1%. Such a fluorescence energy transfer system between confined QDs and AuNPs may pave a new way for designing chemo/biosensing.
研究领域:
分析化学
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纳米技术
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生物传感
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DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2016
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IF 5.886
Youxiu Lin,Qian Zhou,Dianping Tang,Reinhard Niessner,Huanghao Yang,Dietmar Knopp
Mycotoxins, highly toxic secondary metabolites produced by many invading species of filamentous fungi, contaminate different agricultural commodities under favorable temperature and humidity conditions. Herein, we successfully devised a novel signal-on photoelectrochemical immunosensing platform for the quantitative monitoring of mycotoxins (aflatoxin B1, AFB1, used as a model) in foodstuffs on the basis of silver nanolabels-assisted ion-exchange reaction with CdTe quantum dots (QDs) mediated hole-trapping. Initially, a competitive-type immunoreaction was carried out on a high-binding microplate by using silver nanoparticle (AgNP)-labeled AFB1–bovine serum albumin (AFB1–BSA) conjugates as the tags. Then, the carried AgNPs with AFB1–BSA were dissolved by acid to release numerous silver ions, which could induce ion-exchange reaction with the CdTe QDs immobilized on the electrode, thus resulting in formation of surface exciton trapping. Relative to pure CdTe QDs, the formed exciton trapping decreased the photocurrent of the modified electrode. In contrast, the detectable photocurrent increased with the increase of target AFB1 in a dynamic working range from 10 pg mL–1 to 15 ng mL–1 at a low limit of detection (LOD) of 3.0 pg mL–1 under optimal conditions. In addition, the as-prepared photoelectrochemical immunosensing platform also displayed high specificity, good reproducibility, and acceptable method accuracy for detecting naturally contaminated/spiked blank peanut samples with consistent results obtained from the referenced enzyme-linked immunosorbent assay (ELISA) method.
研究领域:
分析化学
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食品科学
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免疫学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Huiling Li,Li Tian,Shuning Yang,Chao Li,Yujia Song,Ruidan Li,Yanjia Guo,Juan Lu
A signal-on solid-state electrochemiluminescence (ECL) sensor based on luminol@carbon nanotubes (luminol@CNTs) and CdTe-ZnS@hydroxyapatite (CdTe-ZnS@HAP) was constructed for the detection of paclitaxel (PTX). In this sensing platform, luminol was used as the main luminophore and CdTe-ZnS was used as a co-reaction accelerator. CNTs and HAP were acted as carriers to adsorb more luminophores and co-reaction promoters. In addition, due to the enhanced effect of PTX on the ECL intensity of the luminol-O 2 system, PTX was introduced as the final detection target. Under the optimal experimental conditions, the ECL intensity change values (ΔI) of the sensor showed a good linear relationship with the logarithm of PTX concentration in the range of 3 × 10 -12 − 3 × 10 -7 molL -1 , and the limit of detection was 1 × 10 -12 mol L -1 (S/N = 3). This method was successfully applied to the determination of trace PTX concentration in serum.
研究领域:
分析化学
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药物检测
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纳米材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
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IF 9.7
Jiannan Sun,Pan Zhang,Ke Yan,Aizhao Pan,Christophe Len,Weiyi Ouyang,Chengyu Shi,Xinyi Shi,Jun Hong
Quantum dots (QDs) with dual-emission property have garnered significant attention as prototype platforms for temperature measurement due to their self-calibration capabilities and high sensitivity. The assembly and property modulation of this materials hold great research value. In this work, we propose a strategy to utilize dendritic mesoporous SiO 2 core–shell spheres to encapsulate dual QDs, enabling the constructing of dual-emission fluorescent temperature sensing system. By encapsulating CsPbBr 3 and CdTe QDs in SiO 2 core–shell spheres, we developed a dual-emission temperature probe that employs two thermometry modes: peak wavelength spacing variation and fluorescence intensity ratio. This probe offers advantages such as high thermal stability, excellent fit, and high sensitivity. Additionally, inspired by the concept of series sliding resistors, we introduced a novel approach to adjust the probe’s sensitivity by treating the fluorescence intensity and peak wavelength of the dual QDs as the “sliding resistor”. This innovation results in a temperature fluorescence sensing system with tunable sensitivity. We also explored the potential applications of these probes in temperature measurement, light-emitting diodes, and fluorescent anti-counterfeiting. Our research presents an effective strategy for the rational design of high-performance dual-emission fluorescence temperature sensing systems with customizable sensitivity.
研究领域:
材料科学
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纳米技术
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光学工程
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）