SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2017
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IF 2.536
Jian Zhu,Hui Chang,Jian-Jun Li,Xin Li,Jun-Wu Zhao
The effect of silicon-coated gold nanoparticles with different gold core diameter and silica shell thickness on the fluorescence emission of CdTe quantum dots (QDs) was investigated. For gold nanoparticles with a diameter of 15 nm, silica coating can only results in fluorescence recover of the bare gold nanoparticle-induced quenching of QDs. However, when the size of gold nanoparticle is increased to 60 nm, fluorescence enhancement of the QDs could be obtained by silica coating. Because of the isolation of the silica shell-reduced quenching effect and local electric field effect , the fluorescence of QDs gets intense firstly and then decreases. The maximum fluorescence enhancement takes place as the silica shell has a thickness of 30 nm. This enhanced fluorescence from silicon-coated gold nanoparticles is demonstrated for sensing of Hg 2 + . Under optimal conditions, the enhanced fluorescence intensity decreases linearly with the concentration of Hg 2 + ranging from 0 to 200 ng/mL. The limit of detection for Hg 2 + is 1.25 ng/mL. Interference test and real samples detection indicate that the influence from other metal ions could be neglected, and the Hg 2 + could be specifically detected.
研究领域:
分析化学
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环境科学
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纳米技术
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2018
·Vol. 42
·期 4
·2640-2648
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IF 3.201
Ji Yang,Ming-Hui Wu,Zheng-Zhong Lin,Zhi-Yong Huang
A novel fluorescence nanoprobe using CdTe quantum dots as signal sources coated with a molecularly imprinted polymer was synthesized by a reverse microemulsion method. The nanoprobe was designed for the detection of leucomalachite green (LMG) in fish samples via synchronous fluorescence quenching based on the inner filter effect. LMG, (3-aminopropyl) triethoxysilane and tetraethyl orthosilicate were used as the template, functional monomer and cross-linker respectively in the probe. A synchronous fluorescence emission of the probe at 260 nm was observed when the wavelength interval was set as 340 nm, and the synchronous fluorescence could be linearly quenched with LMG at concentrations ranging from 0.1 to 20 μmol L−1. The as-prepared nanoprobes were nearly spherical with a diameter of about 50 nm. The detection limit was 23 nmol L−1 (3σ, n = 9) and the recoveries ranged from 96.2% to 104.9% for the fish samples. The results illustrated that the nanoprobe could be used for trace LMG measurement in fish 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
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产品关联
DOI
高影响因子
TALANTA
·
2019
·
IF 4.916
Yujuan Cao,Song Wang,Wei Wu,Hong Peng,Ying Yu,Debin Zhu
An efficient fluorescent probe based on cucurbit[6]uril modified CdTe quantum dots (CB[6]@QDs) was prepared. This novel probe showed significant and selective fluorescence quenching and complexation capacity to p-nitroaniline, its interaction mechanism was studied by both experimental and theoretical methods. Furthermore, a fluorescent method was developed for the determination of p-nitroaniline in different environmental samples. The fluorescence intensity of CB[6]@QDs showed a good linearity response to p-nitroaniline in the concentration range of 2.5 × 10 −7 -3.0 × 10 −6 mol/L with a correlation coefficient (R 2 ) of 0.9976, the limit of detection (LOD) was 6 × 10 −8 mol/L and the limit of quantification (LOQ) was 2 × 10 −7 mol/L. Moreover, about 0–1.5 × 10 −6 mol/L p-nitroaniline were determined in environmental samples, the recoveries were in the range of 88–109% with the relative standard deviations (n = 3) of 1.2–4.5%. Compared with previous fluorescent methods, the present method shortened and simplified the sample pretreatment as well as enhanced the sensitivity and selectivity of analytical method. No further sample pretreatment procedure is needed and the LOD of present method was one order of magnitude less than previous fluorescent methods, showed it is a simple, selective and sensitive method.
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
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Zhiping Zhou,Haiqin Ying,Yanyan Liu,Wanzhen Xu,Yanfei Yang,Yu Luan,Yi Lu,Tianshu Liu,Shui Yu,Wenming Yang
This paper demonstrates a facile method to synthesize surface molecular imprinting polymer (MIP) on SiO 2 -coated CdTe QDs for selective detection of sulfadimidine (SM 2 ). The fluorescent MIP sensor was prepared using cadmium telluride quantum dots (CdTe QDs) as the material of fluorescent signal readout, sulfadimidine as template molecule, 3-aminopropyltriethoxysilane (APTES) as functional monomer and tetraethyloxysilane (TEOS) as cross-linking agent. The CdTe cores were embed in the silicon shells by a sol-gel reaction and then the molecular imprinting layers were immobilized on the surface of the SiO 2 -coated CdTe QDs. Under the optimized conditions, the relative fluorescent intensity weakened in a linear way with the increasing concentration of sulfadimidine in the range of 10–60 μmol L −1 . The practical application of the fluorescent MIP sensor was evaluated by means of analyzing sulfadimidine in the real milk samples. The recoveries were at the range of 90.3–99.6% and the relative standard deviation (RSD) ranged from 1.9 to 3.1%, which indicates the successful synthesis of the fluorescent MIP sensor. This sensor provides an alternative solution for selective determination of sulfadimidine from real milk samples.
研究领域:
分析化学
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材料科学
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生物传感
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产品关联
DOI
高影响因子
DYES AND PIGMENTS
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2018
·
IF 3.767
Ji Yang,Hao Wu,Ming-Hui Wu,Jun Zeng,Zheng-Zhong Lin,Xiao-Mei Chen,Zhi-Yong Huang
Malachite green (MG) is an industrial dye, but has been once abused in aquaculture for disease treatment. Because MG and its metabolite, leucomalachite green (LMG), present great harm to human health, it is essential to rapidly and accurately detect MG and LMG residues in aquatic products. However, the simultaneous screening of MG and LMG is still a challenge to date. In this work, a dual-template molecularly imprinted polymer (MIP) coated CdTe QDs was developed and applied as a nano-probe to simultaneously detect MG and LMG in fish samples via normal and synchronous fluorescence quenching. The molar ratios of templates (MG and LMG) to monomer (APTES) and cross-linker (TEOS), and the amount of CdTe QDs in the probe preparation were optimized. A normal fluorescence emission at 600 nm could be linearly quenched by MG, while the synchronous fluorescence emission at the wavelength interval of 340 nm could be quenched by both LMG and MG. The detection limits of MG and LMG were 17 nmol L −1 and 28 nmol L −1 (3 σ , n = 9), respectively. Based on the equations of Stern-Volmer, MG and LMG could be simultaneously detected without any conversion treatment. The recoveries of MG and LMG in fish samples ranged from 92% to 107% and from 91% to 108%, respectively. The results demonstrated that the as-prepared dual-template CdTe@MIP could be used as a fluorescent probe to rapidly and simultaneously detect MG and LMG in fish samples.
研究领域:
分析化学
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食品安全
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环境科学
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
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2022
·
IF 9.231
Xiaoya Bi,Libo Li,Lijun Luo,Xiaohong Liu,Jiamin Li,Tianyan You
Semiconductor quantum dots (QDs) and tungsten disulfide nanosheets (WS 2 NTs) have been widely studied in photocatalysis and photoelectrochemistry as representative electron donor–acceptor pairs but rarely in fluorescence sensing. In this study, we investigated the effect of WS 2 NTs on the fluorescence signal of cadmium telluride (CdTe) QDs by grafting an aptamer as a bridge between them. The corresponding quenching mechanism was systematically explored, and results described the photoinduced electron transfer (PET) from excited CdTe QDs to WS 2 NTs. Based on these results, a novel ratiometric fluorescence aptasensor was developed for zearalenone (ZEN) determination by innovatively introducing exonuclease I to digest the aptamer of ZEN and control the PET between CdTe QDs and WS 2 NTs. The designed aptasensor exhibited an acceptable linear range and detection limit (0.1 pg mL −1 ), and superior accuracy and selectivity. This ratiometric fluorescence aptasensor was also used to monitor ZEN in rice and corn flour.
研究领域:
分析化学
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食品安全检测
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2016
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IF 4.758
Jian Zhu,Hui Chang,Jian-Jun Li,Xin Li,Jun-Wu Zhao
Both “turn-on” and “turn-off” fluorescent probe for the determination of melamine have been developed by tuning the inner filter effect (IFE) from CdTe quantum dots (QDs) to gold nanoparticles. Because of the melamine-induced aggregation of gold nanoparticles, the first absorption peak of the transverse surface plasmon resonance (SPR) at 520 nm fades down, whereas the second absorption peak of the longitudinal SPR around 620 nm gets intense. The decrease of the transverse SPR reduces the IFE of the bundled CdTe QDs with an emission band at 525 nm (the corresponding particle size is 1.98 nm), which results in the melamine concentration-dependent fluorescence recovery of CdTe QDs. The increase of the longitudinal SPR enhances the IFE of the bundled CdTe QDs with an emission band at 620 nm (the corresponding particle size is 3.68 nm), which results in the melamine concentration-dependent fluorescence decrease of CdTe QDs. The green mode detection with the fluorescence recovery has a linear response for melamine from 20 to 100 ng/mL with a theoretical detection limit of 8 ng/mL. The red mode detection with the fluorescence decrease has a linear response for melamine from 20 to 100 ng/mL with a theoretical detection limit of 11 ng/mL. Interference studies and real samples detection show that the melamine could be specifically detected using this dual-mode fluorescent probe.
研究领域:
分析化学
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纳米技术
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环境科学
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食品安全
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DOI
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 5
·829
·
IF 5.719
Xiao-Lin Yuan,Xiao-Yi Wu,Miao He,Jia-Ping Lai,Hui Sun
A ratiometric fluorescence fiber-optical sensor system (RFFS) merging a Y-type optical fiber spectrometer and CdTe QDs composite functionalized with glutathione and mercaptopropionic acid (GMPA@CdTe-QDs) for highly selective and on-site detection of ciprofloxacin (CIP) in environmental water samples was designed. Our preliminary results suggested that the red fluorescence of the synthesized GMPA@CdTe-QDs was effectively quenched by CIP. Based on this, the RFFS/GMPA@CdTe-QDs system was successfully fabricated and used for highly selective and rapid detection of CIP on site in the concentration range from 0 to 45 μM with the detection limit of 0.90 μM. The established method exhibited good interference resistance to the analogues of CIP and provided a great potential platform for real-time detection of CIP residues in environmental water. In addition, the fluorescence quenching mechanism of GMPA@CdTe-QDs by CIP was also investigated by means of temperature effect, fluorescence lifetime, ultraviolet (UV) visible absorption, and fluorescent spectra. Our results suggested clearly that the red fluorescence of GMPA@CdTe-QDs was quenched by CIP via the photoinduced electron-transfer (PET) mode.Keywords:ratiometric fluorescence;optical fiber sensor;GMPA@CdTe-QDs;ciprofloxacin;on-site detection
研究领域:
环境科学
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分析化学
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产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
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2025
·
IF 5.1
Xiqing Liu,Tao Wang,Yongqing Wang
Fluorescence technology enabled highly sensitive, real-time and multi-scenario detection of lysozyme (Lys). However, fluorescent nanomaterials suffer from aggregation-induced quenching, environmental interference and lack of selective recognition capability. In this work, the ZIF-8 was used as a framework to support red and blue fluorescence quantum dots for constructing ratiometric fluorescence sensor. At the same time, combined with molecular imprinting technology, a Molecular Imprinting Polymers (MIPs)-based ratiometric fluorescence sensor was designed for improving the sensitive and selective. The MIPs-based ratiometric fluorescence sensor exhibited highly sensitively and selectively for the detection of lysozyme. Benefited from ratiometric design, the sensor could realize the effect of visual detection of Lys and the limit of detection (LOD) was reached 0.048 mg/L. The HPLC method was used to further confirm the sensor has the potential for practical application. Furthermore, to the demand of an affordable and portable strategy for visual detection Lys, a dexterous and inexpensive test paper was made in this work.
研究领域:
分析化学
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纳米技术
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荧光传感
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材料科学
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生物传感
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环境监测
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产品关联
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
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2019
·
IF 9.518
Xuwen Gao,Kena Fu,Li Fu,Huaisheng Wang,Bin Zhang,Guizheng Zou
Novel optical labels for biosensing in near-infrared (NIR) region (especially between 800 and 900 nm) are arousing much attention for higher penetrating capability, less scattering and lowered autofluorescent background. Herein, a water-soluble electrochemiluminophore with effective electrochemiluminescence (ECL) around 815 nm is developed via doping dual-stabilizers-capped CdTe nanocrystals (NCs) with Co 2+ species in a growth-doping way. The Co 2+ -doped CdTe NCs not only can preserve the highly-passivated surface states of dual-stabilizers-capped CdTe NCs, but also exhibit efficient red-shifted photoluminescence (PL) and ECL into the promising optical NIR window of 800–900 nm. A spectrum-based ultrasensitive NIR ECL immunosensor is consequently fabricated with the Co 2+ -doped CdTe NCs as tags for the first time, which can selectively and sensitively determine human carcinoembryonic antigen with a wide linearity range from 1 fg/mL to 10 pg/mL and a low limit of detection at 0.2 fg/mL (S/N = 3). This work opens a way to screen novel NIR electrochemiluminophore as well as to modulate the ECL performance of NCs via surface doping and engineering.
研究领域:
材料科学
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纳米技术
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分析化学
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生物传感器
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产品关联
DOI
PubMed
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2023
·Vol. 25
·期 12
·8913-8920
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IF 3.3
Zhen Chi,Jia Xu,Shida Luo,Xia Ran,Xiaojuan Wang,Pingan Liu,Yulu He,Yanmin Kuang,Lijun Guo
Triplet energy transfer (TET) from semiconductor quantum dots (QDs) to molecular triplets has potential applications in photon up-conversion and singlet oxygen generation. Here, we have constructed a complex consisting of CdTe QDs as the donor and 9-anthracenecarboxylic acid (ACA) as the triplet acceptor, and studied the TET pathways and enhanced singlet oxygen generation properties. The results from steady-state and time-resolved spectroscopy demonstrate efficient TET with a total efficiency of over 80% from photoexcited CdTe QDs to ACA. Dynamical analysis clearly indicates two distinctive TET channels – hot electron exchange and thermalized electron exchange – mediating the TET process in the CdTe QDs–ACA complex. The TET efficiencies from hot electron exchange at high energetic levels and thermalized electron exchange on the lowest exciton state can reach ∼27% and ∼85%, respectively, following 530 nm excitation. This efficient TET endows the CdTe QDs–ACA complex with a good capability of generating singlet oxygen species with a yield of up to ∼59%. These findings contribute further insights to the mechanisms of interfacial TET processes and are significant in designing efficient TET systems based on semiconductor nanoparticles and triplet molecules.
研究领域:
材料科学
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光化学
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纳米技术
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2022
·Vol. 414
·期 6
·2065-2078
·
IF 4.478
Ou Panpan,Wu Jiawen,Lin Yu,Tan Xuecai,Wu Yeyu,Chen Zhifan,Wei Fucun,Huang Kejing
Chloramphenicol (CAP) is widely used in the food industry and animal husbandry due to its effective antibiotic effect active against gram-positive and gram-negative microorganisms. However, research shows that it can cause serious adverse reactions and side effects in the human body. In order to effectively monitor the residues of CAP, a novel and simple photoelectrochemical (PEC) sensor for sensitive detection of CAP is fabricated based on M-TiO 2 -CdTe QDs/CdS QDs composite. The results show that the prepared M-TiO 2 not only retains the original morphology and structure of MIL-125(Ti), but also exhibits more abundant pore structure and good photoelectrochemical properties. Compared with M-TiO 2 , the as-prepared M-TiO 2 -CdTe QDs/CdS QDs composite exhibits excellent PEC performances including about ninefold enhancement of photocurrent intensity, which is ascribed to the large surface of M-TiO 2 and the introduction of CdTe QDs and CdS QDs. Based on the selective inhibitory effect of CAP in the photocurrent intensity of the M-TiO 2 -CdTe QDs/CdS QDs PEC system, a novel PEC sensor for CAP concentration determination is constructed. The designed PEC sensor demonstrates a linear range from 1 to 140 nmol L −1 with a detection limit of 0.14 nmol L −1 (S/N = 3). Moreover, the method is applied to real milk samples to quantify the CAP residues with spiked recoveries in the range of 96.3–106%, and the possible detection mechanism of the M-TiO 2 -CdTe QDs/CdS QDs PEC system is also discussed. Graphical abstract
研究领域:
分析化学
·
材料科学
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环境科学
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食品科学
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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）