JOURNAL OF FLUORESCENCE
·
2015
·Vol. 25
·期 4
·897-905
·
IF 1.927
Li Li,Zhang Qiaolin,Ding Yaping,Lu Yaxiang,Cai Xiaoyong,Yu Lurong
Based on the quenching of the fluorescence intensity of thioglycolic acid (TGA)-capped core-shell CdTe/ZnS nanoparticles (NPs) by vanillin, a novel, simple and rapid method for the determination of vanillin was proposed. In aqueous medium, the functionalized core-shell CdTe/ZnS NPs were successfully synthesized with TGA as the capping ligand. TGA-capped core-shell CdTe/ZnS NPs were characterized by using X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy. Factors affecting the vanillin detection were investigated, and the optimum conditions were also determined. Under the optimum conditions, the relative fluorescence intensity of CdTe/ZnS NPs was linearly proportional to vanillin over a concentration range from 9.4 × 10 −7 to 5.2 × 10 −4 M with a correlation coefficient of 0.998 and a detection limit of 2.6 × 10 −7 M. The proposed method was also employed to detect trace vanillin in cookies with satisfactory results.
研究领域:
分析化学
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纳米技术
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食品科学
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DOI
高影响因子
CRYSTENGCOMM
·
2020
·Vol. 22
·期 20
·3474-3481
·
IF 3.117
Xiaopeng Zhou,Jiejun Ren,Xuan Dong,Xicheng Wang,Takatoshi Seto,Yuhua Wang
As a representative of III–V semiconductor materials, InP/ZnS quantum dots are regarded as the star material in the field of light-emitting devices due to their low toxicity and suitable luminescence range. However, there are still some major problems in the preparation process of InP/ZnS QDs, such as phosphine precursors are expensive and difficult to preserve, the nucleation time of short wavelength InP/ZnS QDs is too short and the size distribution is too large. In this paper, we'll replace the traditional tris(trimethylsilyl)phosphine with tris(diethylamino)phosphine as a cheaper phosphine precursor and propose a novel and convenient method for adjusting the luminescence wavelength of InP/ZnS QDs. Different from the traditional method to adjust the emission wavelength by changing the nucleation time, the emission wavelength of InP/ZnS QDs was regulated by changing the number of initially formed cores. Zeolites provide a nucleation site for the InP cores. InP/ZnS QDs that emit between 522 nm and 589 nm were obtained. Moreover, the obtained InP/ZnS QDs have good monochromaticity, and the minimum half-width (half-full width) is up to 48 nm. This method provides a new way to adjust the size of quantum dots with good performance.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
Progress in Natural Science-Materials International
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2023
·
IF 4.7
Haiyan Kang,Hongchao Geng,Sisi Shi,Zhongxian Song,Yuting Dong,Xiaole Yan,Chaohai Wang,Yanli Mao,Qingyun Cai
High concentrations of Cu 2+ exceeding what the required level for the cellular process can changes the properties of protein, affects the normal function of the body, but also affect the body's metabolism, so that the body's immunity appears to decline. Detection of Cu 2+ is important for the environmental monitoring. Here, a fluorescence probe that uses heavy metal-free and properties-superior CuInS 2 /ZnS was proposed for detection of Cu 2+ . The fluorescence intensity of CuInS 2 /ZnS quantum dots (QDs) decreased obviously after Cu 2+ were added, and the intensity with the concentration of Cu 2+ showed excellent linear relation within the scope of 0–50 μM, the LOD down to 0.45 μM, a possible detection mechanism was analyzed. The QDs was further applied to the detection of Cu 2+ in drinking water, manifesting the foreground of the current strategy.
研究领域:
生物化学
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环境科学
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分析化学
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产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2012
·
IF 2.098
Chang Shu,Bin Huang,Xiangdong Chen,Yan Wang,Xuequan Li,Li Ding,Wenying Zhong
Strong fluorescence and low cytotoxicity ZnSe/ZnS quantum dots (QDs) were synthesized by a facile aqueous phase route. It overcame the defects such as instability and low quantum yield of the quantum dots synthesized by early aqueous phase route. l -Glutathione (GSH) and 3-mercaptopropaonic acid (MPA) were used as mixture stabilizers to synthesize high quality ZnSe/ZnS QDs. The samples were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectrometry (XPS) and their optical properties were investigated by using UV–vis spectrophotometer, fluorescence spectrophotometer (FL), IR spectrophotometer and confocal laser scanning microscope. The synthesized ZnSe/ZnS QDs illuminated blue fluorescence under ultraviolet lamp. Its water-soluble property is excellent and the fluorescence intensity of ZnSe/ZnS QDs almost did not change after 4 months at room temperature. The average diameter of ZnSe/ZnS nanocrystals is about 3 nm and quantum yield (QY) could reach to 70.6% after repeat determination. Low cytotoxicity was ensured by investigated SCG7901 and RAW264.7 cells. In comparison with cadmium based nanocrystals, ZnSe/ZnS QDs posed low cytotoxicity. The cells viability remained 96.7% when the QDs concentration was increased to 10 μmol/L. The results in vitro indicate that ZnSe/ZnS QDs-based probes have good stability, low toxicity and biocompatibility for fluorescence imaging in cancer model system.
研究领域:
材料科学
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生物学
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医学
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DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2019
·Vol. 7
·期 17
·2835-2844
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IF 5.047
Hui Zhang,Youshen Wu,Zhenhai Gan,Yuexuan Yang,Yiming Liu,Peng Tang,Daocheng Wu
Accurate and sensitive temperature sensing is of great importance for studying biological activities in cells and tissues. Due to the complexity of the microenvironments, most of the existing thermometry systems cannot meet the needs of accurate intracellular and in vivo temperature sensing with high-sensitivity and low-toxicity. After investigation, we found that the fluorescence intensity of CuInS2/ZnS quantum dots (QDs) is significantly temperature dependent, and these QDs can be used for intracellular and in vivo temperature sensing after being encapsulated by amphiphilic micelles (QD-micelles). These QD-micelles have a size of approximately 10.1 ± 2.5 nm and an emission band of approximately 650 nm with intense photoluminescence (PL). Meanwhile, its high thermal sensitivity of 2% °C−1 at near-room temperature is insensitive to solution pH, ionic strength, and protein concentration. Even at a concentration of 300 μg mL−1, our QD-micelles do not exert cytotoxic effects on HeLa and PC-3 cells. Similar to being dispersed in water, the QD-micelles continue to exhibit a high thermal sensitivity of 2.0% °C−1 intracellular and 2.1% °C−1 in tumor tissues, and the PL intensity (I) and temperature (T) over the physiological temperature range have a good linear correlation. Therefore, they have considerable potential in biomedical applications.
研究领域:
生物医学工程
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纳米医学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Micromachines
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2023
·Vol. 14
·期 5
·902
·
IF 3.4
Yong Xie,Chao Bian,Mingjie Han,Ri Wang,Yang Li,Yuhao Xu,Shanhong Xia
A highly sensitive and accurate dual-signal strategy is developed for trace Cu2+detection based on the inner filter effect (IFE) between Tween 20-gold nanoparticles (AuNPs) and CdSe/ZnS quantum dots (QDs). Tween 20-AuNPs are utilized as colorimetric probes and excellent fluorescent absorbers. The fluorescence of CdSe/ZnS QDs can be quenched efficiently by Tween 20-AuNPs via IFE. In the presence of D-penicillamine, D-penicillamine induces the aggregation of Tween 20-AuNPs and the fluorescent recovery of CdSe/ZnS QDs at high ionic strength. Upon addition of Cu2+, D-penicillamine tends to selectively chelate with Cu2+and then forms the mixed-valence complexes, which consequently inhibits the aggregation of Tween 20-AuNPs and the fluorescent recovery. The dual-signal method is used to quantitatively detect trace Cu2+, with low detection limits of 0.57 μg/L and 0.36 μg/L for colorimetry and fluorescence, respectively. In addition, the proposed method using a portable spectrometer is applied to the detection of Cu2+in water. This sensitive, accurate and miniature sensing system has potential in environmental evaluations.Keywords:fluorescence;colorimetry;copper;CdSe/ZnS quantum dots;gold nanoparticles;inner filter effect
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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产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2021
·Vol. 13
·期 20
·2305-2312
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IF 2.896
Quanxiu Zhou,Zhaofa Li,Qunfang Wang,Liang Peng,Shihe Luo,Feng Long Gu
In this work, poly(styrene-co-maleic anhydride)-capped CdSe/ZnS quantum dots (QDs) aminolyzed with ethanolamine are proposed as fluorescent probes for the detection of Cu2+ and Hg2+, and two different quenching mechanisms are discussed in detail. The coordination abilities of the surface polymer of CdSe/ZnS QDs and two metal ions are calculated by density functional theory (DFT). The photoinduced electron transfer from excited QDs to Cu2+ unoccupied orbitals is enhanced due to the coordination between Cu2+ and the surface polymer of QDs. The electron transfer consumes non-radiative energy and performs fluorescence quenching. For Hg2+, the formation of HgS and the slight aggregation of polymer-coated CdSe/ZnS QDs lead to fluorescence quenching. The probe is sensitive to both Cu2+ and Hg2+, and the response can be detected within 1 min without adjusting the pH. With the addition of a masking agent, Cu2+ and Hg2+ can be exclusively detected in coexistence with another ion. For Cu2+, a linear relation in the concentration ranging from 0.02 to 0.7 μM was found between the relative fluorescence intensity (F0/F) and the concentration of Cu2+; the limit of detection (S/N = 3) is 6.94 nM. For Hg2+, a linear relation ranging from 0.1 to 1.4 μM was found between ln(F0/F) and the concentration of Hg2+; the limit of detection is 20.58 nM.
研究领域:
分析化学
·
材料科学
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DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2021
·
IF 4.821
Haiyu Li,Wan Wang,Zhijuan Wang,Qing Lv,Hua Bai,Qing Zhang
CdSe/ZnS quantum dots (QDs) and 3,3,5,5-tetramethylbenzidine (TMB) were incorporated into a filter paper to produce a paper-based colorimetric device for Hg 2+ detection. Under visible light, the CdSe/ZnS QDs acted as a photocatalyst to oxidize TMB, resulting in blue colorization on the paper. Moreover, Hg 2+ could enhance the photocatalytic activity of CdSe/ZnS QDs and consequently caused an increase in the color intensity of the paper. The color change of the paper-based device can be directly identified by naked-eye observation or captured by a smartphone and analyzed using image processing software for quantitative analysis. Under optimal conditions, a low detection limit of 0.09 µM was achieved. This device was applied for real samples, including tap water and cosmetics, and achieved satisfying results.
研究领域:
分析化学
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环境科学
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产品关联
DOI
高影响因子
Nanoscale Research Letters
·
2014
·Vol. 9
·期 1
·1-13
·
IF 2.481
Li Chao,Ji Yang,Wang Can,Liang Shujing,Pan Fei,Zhang Chunlei,Chen Feng,Fu Hualin,Wang Kan,Cui Daxiang
Successful development of safe and highly effective nanoprobes for targeted imaging of in vivo early gastric cancer is a great challenge. Herein, we choose the CdSe/ZnS (core-shell) quantum dots (QDs) as prototypical materials, synthesized one kind of a new amphiphilic polymer including dentate-like alkyl chains and multiple carboxyl groups, and then used the prepared amphiphilic polymer to modify QDs. The resultant amphiphilic polymer engineered QDs (PQDs) were conjugated with BRCAA1 and Her2 monoclonal antibody, and prepared BRCAA1 antibody- and Her2 antibody-conjugated QDs were used for in vitro MGC803 cell labeling and in vivo targeted imaging of gastric cancer cells. Results showed that the PQDs exhibited good water solubility, strong photoluminescence (PL) intensity, and good biocompatibility. BRCAA1 antibody- and Her2 antibody-conjugated QD nanoprobes successfully realized targeted imaging of in vivo gastric cancer MGC803 cells. In conclusion, BRCAA1 antibody- and Her2 antibody-conjugated PQDs have great potential in applications such as single cell labeling and in vivo tracking, and targeted imaging and therapeutic effects' evaluation of in vivo early gastric cancer cells in the near future.
研究领域:
生物医学工程
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纳米医学
·
肿瘤学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Asif Hassan Raza,Long Li,Shumail Farhan,Wenjing Fu,Yan Wu
Two dimensional (2D) photocatalytic materials are desirable to achieve synergistic charge transfer and segregation. Here, we have developed 2D ZnIn 2 S 4 nanosheet (3–4 nm) that generates more active sites for excellent photocatalytic activity. Further, we have fabricated ZnS quantum dots (QDs) and ZnS nanoparticles (NPs) embedded with ZnIn 2 S 4 nanosheet in the form of ZnS QDs/ZnIn 2 S 4 and ZnS NPs/ZnIn 2 S 4 heterostructures prepared via one step hydrothermal method. The optimal ZnS QDs/ZnIn 2 S 4 presents the hydrogen evolution rate (HER) of 4.5 mmol g −1 h −1 which was approximately 5 and 34 times higher than that of their counterparts as well as about 3 times more efficient than ZnS NPs/ZnIn 2 S 4 heterostructure. The apparent quantum efficiency (AQE) of 21.2% was observed at 350 nm. The work functions determined through Ultraviolet photoelectron spectroscopy (UPS) elaborate the charge transfer mechanism. In situ KPFM validated the surface potential difference between the ZnS QDs and ZnIn 2 S 4 interfaces estimated about 55 mV which was approximately 2 times higher than ZnS NPs/ZnIn 2 S 4 . Theoretical calculation confirms the significant reduction in Gibbs free energy about −0.6 eV. Electron paramagnetic resonance (EPR) spectra suggest the development of a novel S-scheme mechanism and provides a unique insight into the charge transfer, separation and the surface photovoltage of heterostructure photocatalysts.
研究领域:
材料科学
·
化学
·
能源科学
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产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 4
·1-10
·
IF 5.479
Luo Shiqing,Miao Yanming,Guo Junping,Sun Xiaojie,Yan Guiqin
Mesoporous molecularly imprinted polymers (MIPs) containing mangnanese-doped ZnS quantum dots (Mn-ZnS QDs) were prepared for specific recognition and detection of 4-nitrophenol (4-NP). The Mn-ZnS QDs display orange room-temperature phosphorescence with excitation/emission peaks at 295/590 nm and a decay time of 2.0 ms. In the presence of 4-NP, the orange phosphorescence is strongly reduced. Phosphorescence drops linearly in the 0.1–100 μM 4-NP concentration range, and the detection limit is 60 nM. The detection limit is far lower than the maximally allowed 4-NP concentrations in surface water and drinking water as specified by the U.S. Environmental Protection Agency. The intraday ( n = 5) and interday ( n = 6) spiked recovery rates were 96.0–104.5% and 97.9–107.9%, respectively, with relative standard deviations of 0.7–4.8% and 1.8–7.5% respectively. These MIPs integrated the characteristic features of phosphorimetry and molecular imprinting. Potential interference by competitive substances, background fluorescence or scattered light are widely reduced.
Schematic presentation of the synthesis of phosphorescent molecularly-imprinted polymers. A novel probe with manganese-doped ZnS quantum dots (Mn-ZnS QDs) and 3-aminopropyl-triethoxysilane (APTES) as functional monomers and tetraethoxysilane (TEOS) as crosslinking agent was prepared for selective phosphorescence detection of 4-nitrophenol (4-NP).
研究领域:
分析化学
·
环境科学
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DOI
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 17
·2997
·
IF 5.719
Fei Li,Jie Gao,Haocheng Wu,Yijun Li,Xiwen He,Langxing Chen
Roxarsone (ROX) as an organoarsenic feed additive has been widely used in livestock breeding and poultry industry, but ROX can degrade into highly toxic inorganic arsenic species in natural environments to threaten to the environment and human health. Therefore, there is a considerable interest in developing convenient, selective and sensitive methods for the detection of ROX in livestock breeding and poultry industry. In this work, a fluorescent molecularly imprinted polymer (MIPs) probe based on amino-modified Mn-ZnS quantum dots (QDs) has been developed by sol–gel polymerization for specific recognition of ROX. The synthesized MIPs-coated Mn-ZnS QDs (MIPs@Mn-ZnS QDs) have highly selective recognition sites to ROX because there are multi-interactions among the template ROX, functional monomer phenyltrimethoxysilane and the amino-functionalized QDs such as the π–π conjugating effect, hydrogen bonds. Under the optimal conditions, an obvious fluorescence quenching was observed when ROX was added to the solution, and the quenching mechanism could be explained as the photo-induced electron transfer. The MIPs@Mn-ZnS QDs sensor exhibited sensitive response to ROX in the linear range from 3.75×10−8M to 6.25×10−7M (R2= 0.9985) and the limit of detection down to 4.34 nM. Moreover, the fluorescence probe has been applied to the quantitative detection of ROX in feed samples, and the recovery was in the range of 91.9% to 108.0%. The work demonstrated that the prepared MIPs@Mn-ZnS QDs probe has a good potential for rapid and sensitive determination of ROX in complicated samples.
研究领域:
分析化学
·
环境科学
·
食品安全
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DOI
高影响因子
危险品化学品经营许可证（带存储）