JOURNAL OF LUMINESCENCE
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2018
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IF 2.732
Jian Zhu,Si-Nan Wang,Jian-Jun Li,Jun-Wu Zhao
In this work, the effect of core size on the fluorescence emission properties of CdTe@CdS core@shell quantum dots was investigated under the condition of different shell thickness and pH values. Both CdTe and CdTe@CdS core@shell QDs were synthesized in aqueous phase by a simple method, whose optical features were characterized by absorption and fluorescence spectra . High resolution transmission electron microscopy (HRTEM) and X-Ray Diffraction (XRD) were utilized to study the structure and composition of the as-prepared QDs. We can conclude that a smaller initial core exhibits a greater potential for optimizing both fluorescence intensity enhancement and red shift. What's more, there is an optimal shell thickness for the strongest fluorescence intensity while a thicker shell contributes to a larger fluorescence red shift. The optimal pH value is 10.5 for the fluorescence intensity enhancement of the core@shell QDs and a higher pH value is an advantage to expedite the growth rate of CdS shell.
研究领域:
材料科学
·
光学
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DOI
高影响因子
TALANTA
·
2019
·
IF 4.916
Ning Xu,Mingxing Piao,Kamile Arkin,Lina Ren,Jinyu Zhang,Jiawei Hao,Yuxin Zheng,Qingkun Shang
Two different colors of water-soluble core-shell quantum dots CdTe/CdS (green and orange red) have been synthesized and characterized in this paper. The formation of core-shell quantum dots not only improves the fluorescence quantum yield , but also reduces the biological toxicity of quantum dots, and improves the fluorescence lifetime . Two novel fluorescent bioprobes, CdTe/CdS (λ em = 545 nm)-5-Fu and Bio-CdTe/CdS (λ em = 600 nm)-TAM, have been synthesized via the interaction of these two core-shell quantum dots with anticancer drugs (5-Fu) and P-gp inhibitors (TAM), respectively. These two fluorescent probes have been simultaneously used in fluorescence imaging of human breast cancer cells MDA-MB-231/MDR. It can be observed that under the action of P-gp inhibitors distributed on the cell membrane, anticancer drugs can be retained in cancer cells. According to the color of quantum dots on the probe, the visualization results of the action of anticancer drugs and P-gp inhibitors can be obtained. This study shows that to prepare functional bioprobes using core-shell quantum dots CdTe/CdS has great potential in the field of biomedical research such as anticancer drugs.
研究领域:
生物医学
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纳米技术
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肿瘤学
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DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2017
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IF 9.446
Dongting Yue,Xufang Qian,Miao Kan,Meng Ren,Yao Zhu,Lele Jiang,Yixin Zhao
Binary transition metals layered double hydroxides (LDH) such as [NiFe] have been developed as the promising low cost and high performance electrocatalysts for hydrogen evolution. However their applications as co-catalysts in photocatalysis like CdTe/CdS quantum dots (QDs) for hydrogen evolution are limited by their ineffective contact with QDs nanoparticles. We report on the synthesis of the sulfurated [NiFe]-LDH (FeNiS) nanoparticles via the sulfurizing treatment of [NiFe]-based LDH. The sulfurizing treatment can successfully break the 2D [NiFe]-LDH into FeNiS nanoparticles by replacing the OH group via the S group. FeNiS nanoparticles provide more bonding sites for CdTe/CdS QDs due to the sulfur species formed on the FeNiS nanoparticles. The junction between sulfur species and Cd 2+ of CdTe/CdS QDs could facilitate electrons transfer between CdTe/CdS QDs and FeNiS nanoparticles and then significantly enhance their photocatalytic hydrogen production. The photocatalytic activity of FeNiS-CdTe/CdS is much better than [NiFe]-CdTe/CdS QDs and Pt-CdTe/CdS QDs. In all, this novel FeNiS nanoparticles would be a promising low cost co-catalyst for energy and environmental photocatalysis.
研究领域:
材料科学
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能源化学
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环境科学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2014
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IF 3.84
Wanjun Liang,Zhengqing Liu,Shaopu Liu,Jidong Yang,Youqiu He
A kind of novel Glyp-functionalized-CdTe/CdS Quantum dots (QDs) was successfully synthesized by coating Glyp on the surface of the CdTe/CdS QDs. The fluorescence emission of the modified QDs was enhanced greatly but with a low resonance Rayleigh scattering (RRS). When it interacted with calf thymus DNA (ct-DNA), the fluorescence intensity of the system was obviously quenched and the RRS was enhanced, both in good linear relations. Based on the above, a novel fluorescence biosensor for simple, sensitive and selective detection of ct-DNA was developed. Under the optimized conditions, the linear ranges of the functionalized QDs fluorescence intensity and RRS intensity versus the concentration of ct-DNA were 0.109–70 μg mL −1 and 0.482–90 μg mL −1 , respectively. The corresponding detection limits by fluorescence quenching and by RRS enhancing methods were 0.0327 μg mL −1 and 0.146 μg mL −1 , respectively. The proposed method was applied to detect ct-DNA in synthetic sample with satisfactory results.
研究领域:
生物传感器
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分子生物学
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分析化学
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DOI
高影响因子
Analytical Methods
·
2013
·Vol. 5
·期 19
·5309-5316
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IF 1.855
Yizhong Shen,Shaopu Liu,Jian Wang,Dan Li,Xiaodan Wang,Youqiu He
A sensitive and simple method for the determination of chelerythrine (CHE) was developed based on the fluorescence quenching effect of CHE for glutathione (GSH)-capped CdTe/CdS quantum dots (QDs). Under optimum conditions, a good linear relationship was obtained from 0.073 to 24.0 μg mL−1 with a correlation coefficient of 0.9988, and the detection limit (3σ/κ) was 21.9 ng mL−1. The fluorescence quenching mechanism that has been proposed is based on electron transfer supported by ultraviolet-visible (UV-vis) absorption, fluorescence (FL) spectroscopy and electrochemical techniques. The method has been applied to the determination of CHE in synthetic samples and fresh serum samples from healthy humans with satisfactory results. The proposed method manifested several advantages such as high sensitivity, short analysis time, low cost and ease of operation.
研究领域:
分析化学
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生物医学
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DOI
高影响因子
NANOTECHNOLOGY
·
2013
·Vol. 24
·期 20
·205601
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IF 3.842
Bin Xu,Bing Cai,Ming Liu,Hongsong Fan
This study explored a simple and fast method utilizing ultraviolet (UV) irradiation to synthesize CdTe/CdS/ZnS QDs in aqueous solution. Based on the reaction of photolysis and chemical deposition, the CdS and ZnS shell can be successively deposited around the thiol-capped CdTe cores through the interaction of Cd2+/Zn2+ and S2− produced by UV irradiation. The effect of the UV irradiation time, the ratios of thioglycolic acid (TGA)/Cd and TGA/Zn on the shell formation, shell stability, and the photoluminescence (PL) intensity of the QDs, was systematically investigated. Keeping the ratio of TGA/Cd, increasing UV irradiation time from 30 to 120 s, the blue-shift of the fluorescence emission peak position of CdTe/CdS QDs was observed. As the irradiation time increased continuously from 120 to 300 s, the red-shift of the emission peak position was observed. In the total irradiation time, the PL intensity of all the samples was enhanced. By applying 300 s irradiation on the samples, the emission peak was blue-shifted at a fixed TGA/Cd ratio of 1:1 and red-shifted at the ratios of 2:1, 4:1, 8:1, and 13:1. The PL intensity reached its highest value at the ratio of 2:1. The effect of TGA/Zn ratio on ZnS shell formation showed a similar progress. Under an optimum synthesized reaction condition, the particle sizes of CdTe core, CdTe/CdS core–shell and CdTe/CdS/ZnS core–shell–shell QDs were 2.6 nm, 3.4 nm, and 4.6 nm respectively. This study confirmed that with the core–shell–shell structure, CdTe/CdS/ZnS QDs had high anti-oxidability, photostability, and low toxicity. Therefore they can be further used in cell imaging efficiently.
研究领域:
材料科学
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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
ANALYTICA CHIMICA ACTA
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2018
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IF 5.123
Guobin Mao,Qin Zhang,Yeling Yang,Xinghu Ji,Zhike He
Alkaline phosphatase (ALP) is a universal and important hydrolase that has been proved to be associated with several diseases. Herein, a simple and effective method was proposed for ALP detection based on the inner filter effect of p-nitrophenol (pNP) on the fluorescence of CdTe/CdS quantum dots (QDs). For the preparation of CdTe/CdS QDs, Na 2 TeO 3 was used as the Te source, and dithiol as the S source and surface ligand. The as-prepared CdTe/CdS QDs show good fluorescence properties, such as high quantum yield (∼80%), and good chemical/photo-stability. pNP is a hydrolysate of p-nitrophenol phosphate disodium salt under the catalysis of ALP, which could effectively quench the fluorescence of QDs due to the absorption spectra of pNP overlaps well with the excitation spectra of the CdTe/CdS QDs. Therefore, the prepared CdTe/CdS QDs could be applied for ALP detection. A good linear relationship ranging from 2.2 to 220 U/L was obtained with the limit of detection as low as 0.34 U/L. In addition, this method was successfully applied for the assay of ALP in human serum with the satisfactory results.
研究领域:
生物化学
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医学检测
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纳米材料
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
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IF 14.224
Dongyun Liao,Guifang Liang,Yuyao Liu,Wenjun Yan,Yujing Guo,Wenting Liang,Chuan Dong,Lifang Fan
In this work, an efficient and novel photoelectrochemical (PEC) aptasensor for 2,3′,5,5′-tetrachlorobiphenyl (PCB72) was constructed based on [email protected] [email protected] quantum dots ( [email protected] QDs)-decorated TiO 2 nanotubes (TiO 2 NTs). [email protected] QDs were prepared by the combination of CdTe and CdS with a proper lattice mismatch. Due to their large band offsets, [email protected] QDs can reduce undesirable carrier recombination, significantly improving their charge separation efficiency. Then the synthesized [email protected] QDs were modified on TiO 2 NTs ( [email protected] QDs/TiO 2 NTs) through electrostatic adsorption method. The as-prepared composites exhibit a wide visible light absorption range, good PEC activity and high photoelectric conversion efficiency. Also, the PEC aptasensor prepared via the immobilization of anti-PCB72 aptamer on the composites exhibits outstanding analytical performance with high sensitivity and specificity for PCB72 under visible-light irradiation, achieving a detection limit as low as 0.03 ng/L. It was also applied to detect PCB72 in four different real environmental samples with satisfactory results.
研究领域:
环境科学
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分析化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
LUMINESCENCE
·
2014
·Vol. 30
·期 1
·60-66
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IF 1.675
Dan Li,Shaopu Liu,Yizhong Shen,Jidong Yang,Youqiu He
Water-soluble thioglycolic acid (TGA)-capped core/shell CdTe/CdS quantum dots (QDs) were synthesized. The interactions of rhein and emodin with TGA-CdTe/CdS QDs were evaluated by fluorescence and ultraviolet-visible absorption spectroscopy. Experimental results showed that the high fluorescence intensity of TGA-CdTe/CdS QDs could be effectively quenched in the presence of rhein (or emodin) at 570 nm, which may have resulted from an electron transfer process from excited TGA-CdTe/CdS QDs to rhein (or emodin). The quenching intensity was in proportion to the concentration of both rhein and emodin in a certain range. Under optimized conditions, the linear ranges of TGA-CdTe/CdS QDs fluorescence intensity versus the concentration of rhein and emodin were 0.09650–60 µg/mL and 0.1175–70 µg/mL with a correlation coefficient of 0.9984 and 0.9965, respectively. The corresponding detection limits (3σ/S) of rhein and emodin were 28.9 and 35.2 ng/mL, respectively. This proposed method was applied to determine rhein and emodin in human urine samples successfully with remarkable advantages such as high sensitivity, short analysis time, low cost and easy operation. Based on this, a simple, rapid and highly sensitive method to determine rhein (or emodin) was proposed. Copyright © 2014 John Wiley & Sons, Ltd.
研究领域:
分析化学
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材料科学
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药理学
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2014
·
IF 3.84
Jing Wang,Na Li,Feng Shao,Heyou Han
Highly luminescent, good stable and low toxic N-acetyl- l -cysteine (NAC) capped CdTe/CdS@ZnS–SiO 2 near-infrared (NIR)-emitting quantum dots (QDs) were successfully fabricated in aqueous solution via a microwave irradiation reduction route, in which thiol-capped CdTe/CdS QDs were employed as core templates and ZnCl 2 , NAC and tetraethyl orthosilicate as shell precursors. This presented ZnS-like clusters filled hybrid SiO 2 model not only greatly improved the brightness and stability of original CdTe/CdS QDs, but also tremendously decreased the cytotoxicity towards HeLa cells. Furthermore, it was found that Hg 2+ could effectively selective quench the QD NIR emission based on electron transfer process. On the basis of this fact, a simple, rapid and specific method for trace Hg 2+ determination was proposed. Under optimal conditions, the fluorescence intensity decreased linearly with the concentration of Hg 2+ ranging from 5.0 × 10 −9 to 1.0 × 10 −6 M and the limit of detection for Hg 2+ was 1.0 × 10 −9 M ( S / N = 3). As practical applications, the novel NIR sensor has been demonstrated to monitor and image Hg 2+ level in milk power and HeLa cells respectively with satisfactory results obtained.
研究领域:
材料科学
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生物医学
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分析化学
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产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2025
·
IF 7.7
Yanqing Ran,Rui Dai,Xiaoshuo Zhang,Faqiong Zhao,Baizhao Zeng
Epithelial cell adhesion molecule (EpCAM) is a transmembrane glycoprotein and its detection is important for diagnosis and therapeutic prognostic assessment of many cancers. Herein, a highly sensitive electrochemiluminescence (ECL) sensor was developed for its detection. In the ECL sensor, dimercaptosuccinic acid-capped core/shell structured CdTe/CdS quantum dot (QD) was loaded on metal-organic framework material UiO-66(Ce) as electrochemical luminophore; Ti 3 C 2 /Ag composite was introduced for immobilizing EpCAM aptamer. Due to the well immobilization of QD and catalysis of UiO-66(Ce), the obtained luminophore CdTe/CdS QDs@UiO-66(Ce) displayed a strong and stable ECL signal. Furthermore, the Ti 3 C 2 /Ag could act as a co-reactant accelerator to boost the ECL signal. Thus, the resulted sensor had quite strong initial ECL signal for signal-off detection. Further experiment showed that it exhibited good linear response to EpCAM over the concentration range of 1 pg mL −1 − 10 ng mL −1 in pH 7.4 Tris buffer, with a detection limit low to 0.66 pg mL −1 . Additionally, the ECL sensor also presented high selectivity and satisfying reproducibility; its practicability was demonstrated by the successful determination of EpCAM in serum samples.
研究领域:
分析化学
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生物化学
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癌症研究
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纳米技术
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产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2016
·Vol. 4
·期 41
·9856-9863
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IF 5.066
Jun Yao,Xin Gou
In this paper, we report a green, ultrafast and facile aqueous preparation of highly luminescent core–shell CdTe/CdS with significant stability under atmospheric pressure. The surface topography, size, physical shape as well as crystalline structures were studied fully and in depth by adopting a variety of analytical methods such as transmission electron microscopy (TEM) and X-ray diffraction (XRD). The possible mechanism involved in the core growth was proposed and the relevant processes were conjectured too. In this study, we presented a convenient label-free fluorescence nanosensor for the rapid determination of trace mercury, which exhibited many advantages, such as a high sensitivity, excellent selectivity, a rapid response time, a wide linear range and a low limit of detection (LOD). The LOD is down to 1.7 × 10−9 mol L−1, which is lower than that of most other detection methods for mercury.
研究领域:
材料科学
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环境科学
·
分析化学
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产品关联
DOI
高影响因子