ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2019
·
IF 4.527
Kun Yan,Yanhua Liu,Qiulian Yang,Weixia Liu,Ruixin Guo,Jinhong Sui,Zhengyu Yan,Jianqiu Chen
Quantum dots (QDs), as a kind of novel nanomaterial , have the extensive applications in various fields, inevitably leading to increasing risks for the ecological environment. The mobilization of cadmium including metal smelting and subsequent machining for multifarious applications has caused the release of cadmium element into the environment. In this study, we evaluated the potential toxicity of a novel nanoparticle material CdSe QDs, using two green algae Chlorella pyrenoidosa and Scenedesmus obliquus . The impact of CdSe QDs and cadmium ions on algae and the sensitivity of the two algae on target compounds were also considered and compared. Our results showed the algal growth rates and chlorophyll content decreased with increasing exposure concentrations and durations. Moreover, the glutathione levels were decreased while the activities of superoxide dismutase increased, exhibiting their pivotal functions in defeating toxic stress. The increment of malondialdehyde levels revealed that the stresses of CdSe QDs and cadmium ions were contributed to the occurrence of oxidative damage. Our study also indicated that the impact of CdSe QDs was stronger than that of cadmium nitrate and the algal response was also species-specific. In addition, the TEM photographs of the algal ultrastructure showed the presence of surface attachment and uptake of QDs.
研究领域:
环境科学
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毒理学
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水生生物学
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Nano Research
·
2020
·
IF 1.238
Zhong Yi Hu,Dong Ni Han,Qiao Wang,Ze Yuan,Guo Rong Sun,Yao Wang,Jian Guo Tang
Improving the charge transfer of quantum dots and the electron transport layer can greatly improve the efficiency of quantum dot sensitized solar cells (QDSSC). In this work, we used the ligand exchange method to improve the electron transfer efficiency between CdSe QDs and electron transport layer. The short chain-ligand containing disulfide bond and benzene ring conjugated structure was selected as the surface ligand of CdSe QDs. Because of its unique disulfide bond and conjugated structure, the stability and electron transfer efficiency of QDs in TiO2 layer can be effectively improved. The surface ligand has good stability and the ability to promote charge transfer, which can effectively improve the efficiency of QDSSC. By characterizing of fluorescence performance and the analysis of fluorescence lifetime, the surface of this ligand behaves fluorescence quenching phenomenon and life decay phenomenon after modification. Furthermore, photovoltaic devices constructed by the as-prepared dithiocarbamate functionalization of CdSe@TiO2 have also been assembled with the highest PCE of 5.22%.
研究领域:
材料科学
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纳米技术
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太阳能
·
光化学
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2025
·Vol. 15
·期 15
·1189
·
IF 4.3
Yuan-Yuan Liu,Yong-Yue Sun,Yuan Guo,Lu-Lu Chen,Jun-Hao Guo,Haifang Wang
The biological effects of nanoparticles are closely related to their intracellular content and location, both of which are influenced by various factors. This study investigates the effects of surface charge on the uptake, intracellular distribution, and exocytosis of CdSe/ZnS quantum dots (QDs) in Raw264.7 macrophages. Negatively charged 3-mercaptopropanoic acid functionalized QDs (QDs-MPA) show higher cellular uptake than positively charged 2-mercaptoethylamine functionalized QDs (QDs-MEA), and serum enhances the uptake of both types of QDs via protein corona-mediated receptor endocytosis. QDs-MEA primarily enter the cells through clathrin/caveolae-mediated pathways and predominantly accumulate in lysosomes, while QDs-MPA are mainly internalized through clathrin-mediated endocytosis and localize to both lysosomes and mitochondria. Exocytosis of QDs-MPA is faster and more efficient than that of QDs-MEA, though both exhibit limited excretion. In addition to endocytosis and exocytosis, cell division influences intracellular QD content over time. These results reveal the charge-dependent interactions between QDs and macrophages, providing a basis for designing biocompatible nanomaterials.
研究领域:
纳米技术
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细胞生物学
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材料科学
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生物医学工程
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毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Nanomedicine
·
2021
·
IF 6.4
Wanzhen Li,Ping Song,Ying Xin,Zhao Kuang,Qin Liu,Fei Ge,Longbao Zhu,Xuguang Zhang,Yugui Tao,weiwei zhang
Background With the development of bacterial resistance, the range of effective antibiotics is increasingly becoming more limited. The effective use of nanoscale antimicrobial peptides (AP) in therapeutic and diagnostic methods is a strategy for new antibiotics.Methods Combining both AP and cadmium selenide (CdSe) into a composite material may result in a reagent with novel properties, such as enhanced antibacterial activity, fluorescence and favorable stability in aqueous solution.Results AP-loaded CdSe NPs (AP-CdSe NPs) showed strong antibacterial activity against multidrug-resistant (MDR) Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) in vitro and in vivo. Colony-forming unit (CFU) and minimum inhibitory concentration (MIC) assays showed that AP-CdSe NPs have highly effective antibacterial activity. The quantitative analysis of apoptosis by flow cytometry analysis further confirmed that MDR E. coli and S. aureus treated with AP-CdSe NPs had death rates of 98.76% and 99.13%, respectively. Also, AP-CdSe NPs was found to inhibit bacterial activity in an in vivo bacteremia model in mice infected with S. aureus. In addition, the antibacterial mechanism of AP-CdSe NPs was determined by RNA sequencing analysis. Gene ontology (GO) analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis revealed the molecular mechanism of the antibacterial effect of AP-CdSe NPs. Importantly, histopathology analysis, and hematological toxicity analysis indicated that AP-CdSe NPs had few side effects.Conclusion These results demonstrate that AP loaded on CdSe NPs had a higher water solubility, bioavailability and antibacterial effect compared with raw AP. This study reports findings that are helpful for the design and development of antibacterial treatment strategies based on AP.
研究领域:
纳米技术
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微生物学
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药学
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分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2015
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IF 12.881
Shuang Jiao,Qing Shen,Iván Mora-Seró,Jin Wang,Zhenxiao Pan,Ke Zhao,Yuki Kuga,Xinhua Zhong,Juan Bisquert
Even though previously reported CdTe/CdSe type-II core/shell QD sensitizers possess intrinsic superior optoelectronic properties (such as wide absorption range, fast charge separation, and slow charge recombination) in serving as light absorbers, the efficiency of the resultant solar cell is still limited by the relatively low photovoltage. To further enhance photovoltage and cell efficiency accordingly, ZnTe/CdSe type-II core/shell QDs with much larger conduction band (CB) offset in comparison with that of CdTe/CdSe (1.22 eV vs 0.27 eV) are adopted as sensitizers in the construction of quantum dot sensitized solar cells (QDSCs). The augment of band offset produces an increase of the charge accumulation across the QD/TiO2 interface under illumination and induces stronger dipole effects, therefore bringing forward an upward shift of the TiO2 CB edge after sensitization and resulting in enhancement of the photovoltage of the resultant cell devices. The variation of relative chemical capacitance, Cμ, between ZnTe/CdSe and reference CdTe/CdSe cells extracted from impedance spectroscopy (IS) characterization under dark and illumination conditions clearly demonstrates that, under light irradiation conditions, the sensitization of ZnTe/CdSe QDs upshifts the CB edge of TiO2 by the level of ∼50 mV related to that in the reference cell and results in the enhancement of Voc of the corresponding cell devices. In addition, charge extraction measurements have also confirmed the photovoltage enhancement in the ZnTe/CdSe cell related to reference CdTe/CdSe cell. Furthermore, transient grating (TG) measurements have revealed a faster electron injection rate for the ZnTe/CdSe-based QDSCs in comparison with the CdSe cells. The resultant ZnTe/CdSe QD-based QDSCs exhibit a champion power conversion efficiency of 7.17% and a certified efficiency of 6.82% under AM 1.5G full one sun illumination, which is, as far as we know, one of the highest efficiencies for liquid-junction QDSCs.
研究领域:
材料科学
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纳米技术
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太阳能
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光伏
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Nanomedicine
·
2018
·
IF 4.37
Fei Yu,Ya-min Xiong,Song-cheng Yu,Lei-liang He,Shan-shan Niu,Yu-ming Wu,Jie Liu,Ling-bo Qu,Li-e Liu,Yong-jun Wu
Background DNA methyltransferase 1 (DNMT1), a dominant enzyme responsible for the transfer of a methyl group from the universal methyl donor to the 5-position of cytosine residues in DNA, is essential for mammalian development and closely related to cancer and a variety of age-related chronic diseases. DNMT1 has become a useful biomarker in early disease diagnosis and a potential therapeutic target in cancer therapy and drug development. However, till now, most of the studies on DNA methyltransferase (MTase) detection have focused on the prokaryote MTase and its activity. Methods A magnetic fluorescence-linked immunosorbent assay (FLISA) using CdSe/ZnS quantum dots as fluorescent probes was proposed for the rapid and sensitive detection of the DNMT1 level in this study. Key factors that affect the precision and accuracy of the determination of DNMT1 were optimized. Results Under the optimal conditions, the limit of detection was 0.1 ng/mL, the linear range was 0.1–1,500 ng/mL, the recovery was 91.67%–106.50%, and the relative standard deviations of intra- and inter-assays were respectively 5.45%–11.29% and 7.03%–11.25%. The cross-reactivity rates with DNA methyltransferases 3a and 3b were only 4.0% and 9.4%, respectively. Furthermore, FLISA was successfully used to detect the levels of DNMT1 in human serum samples, and compared with commercial enzyme-linked immunosorbent assay (ELISA) kits. The results revealed that there was a good correlation between FLISA and commercial ELISA kits (correlation coefficient r =0.866, p =0.001). The linear scope of FLISA was broader than ELISA, and the measurement time was much shorter than ELISA kits. Conclusion These indicated that the proposed FLISA method was sensitive and high throughput and can quickly screen the level of DNMT1 in serum samples.
研究领域:
生物技术
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医学诊断
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分子生物学
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癌症研究
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Changlin Li,Shangrong Chen,Xiangxiang Gao,Wei Zhang,Yanfang Wang
The photoelectrochemical (PEC) performance of ZnO is restricted by its low light absorption ability and high recombination rate of photogenerated carriers. In order to overcome these drawbacks, ZnO/CdS/CdSe heterostructures are prepared on Zn foil substrate using facile three-step methods containing hydrothermal growth, successive ionic layer adsorption reaction (SILAR) and modified chemical bath deposition (CBD). The effects of process parameters containing the number of SILAR cycles of CdS, sensitization sequence of CdS and CdSe, and precursors of CdSe on PEC performance of ZnO/CdS/CdSe heterostructures, and ZnO NRAs on PEC performance of CdS/CdSe co-sensitizer have been scrutinized. Through CdS and CdSe co-sensitization, a layer of CdS/CdSe nanofilm is conformally deposited on ZnO nanorod arrays (NRAs) observed by transmission electron microscopy (TEM). Both the visible-light absorption ability and separation efficiency of photogenerated carriers of ZnO NRAs are significantly enhanced evidenced by UV–vis diffuse reflectance absorption spectra , photoluminescence (PL) spectra and electrochemical impedance spectra. Due to the synergistic effect of ZnO NRAs and CdS/CdSe co-sensitizer, the ZnO/CdS/CdSe heterostructures with five SILAR cycles and one modified CBD cycle (ZnO-CdS5-CdSe) show efficient PEC properties with photocurrent density of 6.244 mA/cm 2 at −0.2 V vs Ag/AgCl under light illumination of 100 mW/cm 2 , which are 57.28 and 4.73 times higher than those of pristine ZnO NRAs and CdS/CdSe clusters, respectively. Moreover, the photoconversion efficiency and incident photon to current conversion efficiency (IPCE) of the ZnO-CdS5-CdSe photoanode reach 4.381% and 80.92%, respectively. The heterostructures based on Zn foil substrate in this study can be a promising candidate for practical PEC application and other applications such as photocatalytic degradation and solar cell due to its low manufacturing cost, large-scale production and efficient PEC ability.
研究领域:
材料科学
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光电化学
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纳米技术
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太阳能转换
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2017
·Vol. 10
·期 1
·51-58
·
IF 1.9
Xiao-Li Du,Tian-Fang Kang,Li-Ping Lu,Shui-Yuan Cheng
A novel electrochemiluminescence (ECL) biosensor based on CdSe@CdS quantum dots (QDs) functionalized MoS2 modified electrode was developed for sensitive detection of Pb(II) using HRP-mimicking DNAzyme biocatalytic precipitation (BCP) for ECL signal quenching. Polycationic poly(diallyldimethylammonium chloride) (PDDA) and negatively charged QDs were adsorbed on the surface of MoS2, in sequence, to form the MoS2–QDs composites, which were employed as a matrix for the immobilization of the G-rich DNA strand, i.e., T30695. The MoS2–QDs were characterized by UV-vis absorption spectroscopy, fluorescence spectroscopy, energy dispersive spectrometry, transmission electron microscopy, and field emission scanning electron microscopy. CdSe@CdS QDs can produce an ECL signal using 0.1 M K2S2O8 as a co-reactant. T30695 can combine with Pb(II) ions to form a stable parallel G-quadruplex. The G-quadruplex can further combine with hemin to form DNAzyme, which can catalyze H2O2 and oxidize 4-chloro-1-naphthol (4-CN) to produce an insoluble precipitation of benzo-4-chlorohexadienone on the surface of the sensor. When the concentration of Pb(II) in the solution was increased, more of DNAzyme was generated and subsequently more 4-CN molecules were oxidized catalytically, leading to a decrease of the ECL signal. Using this quenching strategy, the ECL signal of the biosensor was linearly dependent on the logarithm of the Pb(II) concentration ranging from 1.0 × 10−15 to 1.0 × 10−11 M with a detection limit of 0.98 f M. The stability and selectivity of the sensor were also investigated. The sensor was applied in the determination of Pb(II) in the real water samples and satisfactory results were obtained.
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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生物传感器
✓ 已验证
产品关联
DOI
高影响因子
Science China-Materials
·
2024
·Vol. 67
·期 7
·2302-2310
·
IF 6.8
Ruan Qiaohui,Cui Yanyu,Lin Zhuohan,Zhang Xue,Zhang Xin,Li Yan,Ma Xiang
Chiral colloidal semiconductor magic-sized clusters (MSCs) with dimensions less than 2 nm provide abundant surface binding sites for chiral ligands and thus have great potential for chiral semiconductor nanomaterial applications. However, the preparation and optical characterization of chiral MSCs are rarely reported in the past. In this study, chiral MSCs in a single-ensemble form, containing CdS MSCs with a unique sharp absorption peak at 366 nm and CdSe MSCs at 420 nm, were synthesized for the first time in aqueous solution at room temperature using chiral cysteine as ligands. The optical activity of the prepared chiral MSCs can be easily adjusted by varying the amount of chiral ligands added. The maximum absorption asymmetry factors of the prepared chiral CdS MSCs and CdSe MSCs reach 3.6 × 10 −4 and 5.6 × 10 −4 , respectively. The experiment results indicate that the chiral optical properties of the prepared MSCs may originate from the ligand-induced atomic rearrangement on the surface of MSCs. This study not only provides a general method for obtaining chiral MSCs, but also opens the way for research and applications of chiral MSCs.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2014
·Vol. 16
·期 2
·1-11
·
IF 2.278
Zhang Qiang,Yang Ping,Chen Hsueh Shin,Huang Baibiao,Shen Jianxing
Phosphonic and carboxylic acids were used as capping agents to fabricate CdSe nanocrystals (NCs) through organic synthesis, leading to a controlled growth of the NCs with adjustable morphologies from dots to rods. The binding energies and steric hindrance of ligands dramatically affected the growth kinetics of CdSe NCs, and therefore the resulting geometry of NCs. The detailed investigations of ligand effect on the growth of NCs and an efficient control over the NCs morphology were presented. CdSe nanorods (NRs) with various aspect ratios were created for studying relation between the diameter of NRs and photoluminescence (PL). Consequently, a synergic use of PL spectra and transmission electron microscopy images allowed us to systematically investigate the relationship between morphology and PL properties of as-prepared CdSe rods. The PL properties of CdSe NRs were finally found to be strongly diameter dependent and weakly related to their lengths.
研究领域:
纳米材料
·
半导体纳米晶体
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光电子学
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胶体化学
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光物理
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2022
·
IF 6.14
Guo Li,Changxue Dong,Genshuai Sun,Mingzhe Li,Xin Cao,Li Zhou,Tao Chen,Fan Yang
Doping is a simple method to modulate the electronic configuration of semiconductor photocatalysts. This study regulated the energy band structure of CdSe nanosheets by Ag doping, which reduced the energy bandwidth of CdSe nanosheets by increasing the carrier density, thereby improving the efficiency of the photocatalytic reduction of uranium by CdSe nanosheets. A 96% removal of U(VI) was achieved by 3% Ag-CdSe nanosheets, which was 1.9 and 1.2 times higher than that of pristine CdSe nanosheets (50%), and 1% Ag-CdSe nanosheets (81%), respectively. Additionally, at pH = 4.0 and a solid–liquid ratio of 0.25, the reduction of uranium by 3% Ag-CdSe nanosheets (765 mg/g) was 2.2 times higher than that of pristine CdSe nanosheets (345.6 mg/g). This study provides a new idea for other efficient photocatalysts designed for uranium reduction.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2012
·Vol. 19
·期 5
·1732-1739
·
IF 5.925
Zhipeng Huang,Lei Pan,Peng Zhong,Maoying Li,Feng Tian,Chi Zhang
Graphical Bird on a quantum wire : Monodisperse Ag 2 S (or Ag 2 Se) ZnSe quantum wires can be synthesized at 120 °C with the assistance of Ag 2 S. These quantum wires are uniform in structure and morphology and have an aspect ratio of larger than 100. This method can be also used to fabricate CdSe quantum rods. A facile method for the low-cost and large-scale production of ultralong Ag 2 S (or Ag 2 Se) ZnSe quantum wires has been developed. ZnSe quantum wires (diameter≈4 nm) with high uniformity in their crystal structure and diameter can be synthesized by using a catalyst-assisted growth approach with Ag 2 S nanoparticles as a catalyst. The influence of the growth temperature, time, and type of catalytic particle on the morphology of the ZnSe quantum wires was systematically explored. Besides Ag 2 S, Ag 2 Se nanoparticles can also be adopted as the catalyst for the growth of ZnSe wires. This method can also be applied to the fabrication of uniform CdSe nanorods. This method is convenient for the controllable fabrication of metal selenides and is of importance for exploring fundamental nanoscale semiconductor physics, as well as for affording technological devices with optimized characteristics.
研究领域:
材料科学
·
纳米技术
·
半导体物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）