CRYSTENGCOMM
·
2013
·Vol. 16
·期 8
·1547-1552
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IF 3.879
Yang Huang,Zanyong Zhuang,Xiaogang Xue,Jinsheng Zheng,Zhang Lin
So far, the photoluminescence (PL) properties optimization of mercaptopropionic acid (MPA) capped CdTe has yet to be understood from a perspective of growth kinetics. In this work, the growth kinetics, size distribution and PL properties of CdTe quantum dots (QDs) grown in MPA aqueous solutions of two extreme concentrations, i.e. 0 mM and 50 mM, were systematically investigated. The studies revealed that CdTe QDs coarsen in low and high concentrations of MPA followed different growth kinetics, i.e. a mixed OA (Oriented Attachment)–OR (Ostwald Ripening) growth and an OA dominated growth, respectively. Moreover, the OR growth in a low MPA concentration solution was found to be disadvantageous for narrowing the size distribution but favourable for enhancing fluorescence, while the OA growth in a high MPA concentration solution is beneficial for focusing and controlling the particle size. Further activation energy calculations indicate that the extra MPA that forbids the OR growth and retards the OA growth is favourable for slowing the particle growth, thus achieving CdTe QDs with a controlled size and narrow distribution. Furthermore, the kinetics study reveals how the introduction of concentrated surface ligands affects the PL properties (FWHM and intensity) of the material.
研究领域:
材料科学
·
化学
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2019
·Vol. 30
·期 24
·21177-21184
·
IF 2.195
Zheng Jiahong,Cheng Kangkang,Yu Pengfei
A simple fluorescence sensor for the detection of sulfadimidine (SM 2 ) was fabricated by molecular imprinting technology. Cadmium telluride quantum dots (CdTe QDs) as the fluorescent material, 3-aminopropyltriethoxysilane (APTES) as functional monomer, sulfadimidine as template molecule and tetraethoxysilane (TEOS) as cross-linker, the CdTe QDs were embedded in silica nano-particles by reverse microemulsion method. Under optimal detection condition, response is linear in the 2–30 μmol L −1 SM 2 concentration condition with the detection limit was 0.4 μmol L −1 . In addition, the correlation coefficient was 0.9857 and the imprinting factor was 4.82. The fluorescent probe was successfully applied to the determination of SM 2 in tap water and milk sample with the spiked recoveries ranging from 99.8 to 103.2%. It gets a good specific recognition ability and potential practical application value.
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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DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2021
·
IF 4.821
Yeqing Xu,Ting Huang,Bo Hu,Minjia Meng,Yongsheng Yan
Molecular imprinted ratiometric fluorescent analysis method has been a popular method for the quantitative and qualitative tests of target analysis yet encounters low detection efficiency caused by the deep embedment and uneven distribution of fluorescent monomers, even the embedding rate of fluorescent monomer directly affects the visual detection effect. Herein, the ratiometric fluorescent molecularly imprinted polymers (F-PDA/CdTe QDs@SiO 2 @MIPs) based fluorescent polydopamine (F-PDA) and CdTe quantum dots (CdTe QDs) was successfully synthesized to detect p -nitrophenol ( p -NP) selectively and visually. F-PDA was firstly used in the synthesis of ratiometric fluorescent molecularly imprinted polymers to serve as both fluorescent monomer and functional monomer, which greatly shorten the detection time while reducing the fluorescence loss caused by polymer coating. The test results showed that the p -NP quenched the fluorescent of F-PDA via electron transfer. Meanwhile, F-PDA/CdTe QDs@SiO 2 @MIPs enabled to visually detect a low detection limit of p -NP (56.68 nM) within 2.0 min by naked eyes. The detection time was as fast as quantum dots detect targets directly and the detection limit was well below the standard concentration of p -NP in drinking water. Finally, the F-PDA/CdTe QDs@SiO 2 @MIPs realize the detection of p -NP in the drinking and wastewater respectively.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
Journal of Biophotonics
·
2016
·Vol. 10
·期 5
·657-663
·
IF 3.818
Jingjing Yao,Guangxu Xing,Junling Han,Yaning Sun,Fangyu Wang,Ruiguang Deng,Xiaofei Hu,Gaiping Zhang
Novel direct and indirect competitive fluorescence-linked immunosorbent assays ( c FLISA and ic FLISA) for detection of ochratoxin A (OTA) were described using CdTe quantum dots (QDs) as fluorescent label. CdTe QDs were successfully synthesized, which had an emission wavelength of 615 nm. The high purity monoclonal antibody against OTA was prepared through cell thawing and the octylic acid-ammonium sulfate method. The OTA MAbs were successfully coupled with CdTe QDs, and which also retained the original biological activity. The 50% inhibition values (IC 50 ) of the c FLISA and ic FLISA were 0.630 ng/mL, 0.234 ng/mL, the limits of detection (LOD) were 7.06 × 10 –3 and 4.15 × 10 –3 ng/mL, and detection ranges were 7.06 × 10 –3 − 18.34 ng/mL and 4.15 × 10 –3 − 4.88 ng/mL, in-order. The recoveries were 96.0–104.7% along with coefficients of variation (CVs) below 10%. The FLISA provided novel method for determination of OTA and the potential of MAb–CdTe QDs for the establishment of fluorescent immunochromatographic test strip.
研究领域:
分析化学
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食品安全
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毒理学
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免疫学
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产品关联
DOI
PubMed
高影响因子
MARINE POLLUTION BULLETIN
·
2019
·
IF 3.782
Tian Shi,Liju Tan,Hailu Fu,Jiangtao Wang
A molecularly imprinted polymer (MIP) anchored on the surface of CdTe quantum dots (QDs) was fabricated and used as a fluorescent probe for sulfadiazine (SDZ) detection in seawater. CdTe QDs was used as photoluminescent material, SDZ as the template, 3-aminopropyltriethoxysilane (APTES) as the functional monomer and tetraethyl orthosilicate (TEOS) as the cross-linking agent. Characterizations of MIP-QDs were analyzed by Fourier transform infrared (FT-IR), Transmission electron microscopy (TEM) and Scanning electron microscope (SEM). The conditions were optimized for the detection of MIP-QDs to SDZ. The mechanism of fluorescence quenching was studied by UV–Vis absorption spectroscopy and fluorescence spectroscopy. Under optimal conditions, the fluorescence intensity of MIP-QDs decreased linearly between 4‐ and 20 μM SDZ with a good correlation coefficient of 0.995. The limit of detection is 0.67 μM and the recovery is between 91.8 and 109.4% with RSD lower than 3.9%. These results indicated that MIP-QDs for SDZ detection in seawater was developed successfully.
研究领域:
分析化学
·
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
·
2015
·
IF 2.711
Chunxiao Qiu,Youhong Xing,Wenming Yang,Zhiping Zhou,Yingchun Wang,Hong Liu,Wanzhen Xu
Twenty molecular dynamics (MD) simulations of molecular imprinting prepolymerization systems had been performed to optimize the imprinting shell of the fluorescent sensor. The results revealed that the system with a Bisphenol A (BPA): 3-aminopropyltriethoxysilane (APTES): tetraethylorthosilicate (TEOS) mole ratio of 10:15:60 had the most stable template (T)-functional monomer (FM) cluster. Correspondingly, five kinds of imprinted and non-imprinted polymers were synthesized to assess the reliability and validity of the simulation results. Hybrid SiO 2 -coated CdTe NCs (HS-QD) were synthesized by a simple reflux procedure including a sol-gel reaction that resulted in the formation of a hybrid SiO 2 layer with CdS-like clusters on a CdTe core. Based on the optimal component ratio of the prepolymerization system, MIP shells were anchored on the surface of HS-QD to build a fluorescent MIP sensor. A linear relationship between relative fluorescence intensity and the concentration of BPA had been obtained covering the concentration range of 0.05–10 μmol L −1 with a limit of detection of 6 nmol L −1 . The feasibility of the fluorescent sensor was successfully evaluated through the analysis of BPA in river water and milk. The recoveries are above 96.31%, and the relative standard deviation (RSD) ranged from 1.55% to 2.78%.
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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DOI
高影响因子
RSC Advances
·
2015
·Vol. 6
·期 1
·481-488
·
IF 3.84
Jinna Wang,Guanhong Xu,Fangdi Wei,Jing Yang,Ping Zhou,Qin Hu
A novel fluorescence method was established for detecting sialic acid (SA) by using phenylboronic acid (PBA)-functionalized Fe3O4/CdTe magnetic nanoparticles as fluorescence probe. Initially, Fe3O4 nanoparticles were modified with amino groups, and then 3-mercapto propionic acid-stabilized CdTe quantum dots (QDs) were covalently linked to the amino-modified Fe3O4 nanoparticles to form Fe3O4/CdTe magnetic fluorescence nanoparticles. Finally, PBA was introduced on the surface of Fe3O4/CdTe to form PBA-functionalized Fe3O4/CdTe magnetic fluorescence nanoparticles. This kind of nanoparticle can specifically recognize SA and its fluorescence intensity is quenched by SA. In addition, the conjugate of the nanoparticles and SA is easy to separate from the sample matrix due to its magnetic properties. Therefore, this nanoparticle can be used as a fluorescence probe to detect SA. Under optimal conditions, the fluorescence intensity of the nano probe was found to be inversely linear with the concentration of SA in a wide range of 50 μg ml−1–1.50 mg ml−1, and the limit of detection was 16 μg ml−1. The PBA-functionalized Fe3O4/CdTe nano probe was applied to the determination of SA in infant formula, and the result showed high accuracy and precision. The PBA-functionalized Fe3O4/CdTe nano probe has the potential to be used to monitor SA in food.
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
APPLIED CLAY SCIENCE
·
2022
·
IF 5.907
Houmei You,Kewei Zhang,Xiangkun Zhang,Huiping Ding,Yiwen Shen,Yongjun Feng,Jinpeng Hou,WeiliangTian
Quantum dots luminescent films have great potential for application in lasers, optoelectronics , solid-state light-emitting diodes, and optical devices. This work describes multilayer ordered vermiculite-based luminescent thin films (VLFs) with 2D architecture via layer-by-layer assembly of PDDA-modified CdTe QDs on exfoliated vermiculite (VMT). The assembly of negative CdTe QDs and negative VMT was achieved, overcoming the nonluminance of solid CdTe QDs. The ordered VLFs possess periodic layered structures involving heterogeneous superlattices associated with individual VMT layers. The rational combination of luminescent components affords precise control of the emission wavelength and intensity, resulting in a gradual change in luminescence intensity in the selected light-emitting spectral region upon increasing the number of deposition cycles. Compared to the CdTe QDs, the fluorescence lifetime of VLFs is improved owing to the ordered structure. This work provides a facile approach to fabricate heterogeneous VLFs with high luminous properties and optical stability, which is expected to prevent easy aggregation of luminescent materials and can be potentially applied in light displays and multicolor optical and optoelectronic devices .
研究领域:
材料科学
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光电子学
·
纳米技术
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产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2014
·
IF 3.84
Yizhong Shen,Shaopu Liu,Jidong Yang,Linlin Wang,Xuanping Tan,Youqiu He
A novel and sensitive turn-on fluorescent biosensor for herring sperm DNA (hsDNA) detecting was designed based on hsDNA-induced fluorescence enhancement of Sm 3+ -modulated glutathione (GSH)-capped CdTe quantum dots (QDs). The fluorescent biosensor was based on the following two properties. First, the high fluorescence of GSH-capped CdTe QDs could be effectively quenched by Sm 3+ due to the binding of Sm 3+ to the GSH on the surface of the QDs and the electron transfer from the photoexcited GSH-capped CdTe QDs to Sm 3+ . Second, the high affinity of hsDNA to Sm 3+ enabled Sm 3+ to be dissociated from the surface of GSH-capped CdTe QDs to form more stable complex with hsDNA in aqueous solution, thereby enhancing the fluorescence of Sm 3+ -modulated GSH-capped CdTe QDs. Experimental results showed that the enhanced fluorescence intensity of Sm 3+ -modulated GSH-capped CdTe QDs was directly proportional to the concentration of hsDNA in the range from 0.012 to 14.0 μg mL −1 with a good correlation coefficient of 0.9977, and the detection limit (3 σ / S ) was 3.61 ng mL −1 . To further investigate perfect analysis performance, the developed biosensor was applied to the determination of hsDNA in synthetic samples and human fresh serum samples with satisfactory results.
研究领域:
生物化学
·
分析化学
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DOI
高影响因子
FOOD CHEMISTRY
·
2020
·
IF 6.306
Hengye Chen,Ou Hu,Yao Fan,Lu Xu,Lei Zhang,Wei Lan,Ying Hu,Xingrui Xie,Lixia Ma,Yuanbin She,Haiyan Fu
The needing of rapid and sensitive detection method for pesticides is increasing, to facilitate its detection without complicated instruments. Herein, a novel paper-based senor was developed for the visual detection of three carbamate pesticides (metolcarb, carbofuran, and carbaryl) based on CdTe quantum dots (QDs) and nano zinc 5, 10, 15, 20-tetra(4-pyridyl)-21 H -23 H -porphine (nano ZnTPyP) with a “turn-off-on” mode. This fluorescence sensing model could be applied in the highly selective and sensitive detection of carbamate pesticides both by fluorescence spectrometry or paper-based sensors. Based on the extracted RGB color values of paper, the partial least squares regression (PLSR) was used to accurately quantify the concentrations of carbamate pesticides in different food matrices (apple, cabbage and tea water). This method featured in high speed, low price and high accuracy, and provided a new strategy for the detection of food safety.
研究领域:
食品安全检测
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分析化学
·
环境科学
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产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2016
·Vol. 5
·期 4
·826-833
·
IF 4.872
Zhenzhen Lin,Shuzhen Lv,Kangyao Zhang,Dianping Tang
This work designs a simple low-cost visual fluorescence immunoassay for disease-related biomarkers (carcinoembryonic antigen, CEA, used as a model protein) in biological fluids, based on the structural and optical transformation of CdTe quantum dots (QDs) immobilized on paper induced by dissolved silver ions (Ag+) from silver nanoparticles (AgNPs) via a cation-exchange reaction. A sandwich-type immunoreaction was initially carried out in a removable polystyrene high-binding microplate coated with monoclonal anti-CEA capture antibody by using AgNP-labeled polyclonal anti-CEA antibody as the detection antibody. Thereafter, the carried AgNPs accompanying the sandwiched immunocomplexes were dissolved by acid to release numerous silver ions, which induced the ion-exchange reaction with the immobilized CdTe QDs on the paper (attached onto the microplate lid) for the Cd-to-Ag transformation, thus resulting in the quenching of the visual fluorescence from the CdTe QDs owing to Ag2Te formation. Under optimal conditions, the fluorescence intensity decreased with the increasing CEA concentration from 0.02 to 50 ng mL−1 with a detection limit of 5.6 pg mL−1. Further, a visual assay based on a CdTe QD-based paper sensor was developed for CEA detection, and 5.0 pg mL−1 CEA could be discriminated with the naked eye. In addition, our strategy displayed high specificity, good reproducibility and acceptable accuracy for analyzing human serum specimens with consistent results obtained using the commercialized enzyme-linked immunosorbent assay (ELISA) method.
研究领域:
分析化学
·
生物传感器
·
生物医学工程
·
分子诊断
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产品关联
DOI
PubMed
高影响因子
NANOTECHNOLOGY
·
2013
·Vol. 24
·期 20
·205601
·
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
·
生物医学工程
·
纳米技术
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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）