共查询到20条相似文献,搜索用时 15 毫秒
1.
量子点由于其量子效应而具有既不同于体相材料又有别于一般分子的优异光学性能,因此在生物医学领域,特别是在生物标记中具有良好的应用前景。II–VI族量子点由于其荧光发射波长几乎覆盖了整个可见光区而引起人们的关注,其中在有机体系中合成油溶性II–VI族量子点具有反应产物稳定,量子产率高,并且可以制备性能更加优异的核–壳结构的量子点(CdSe/ZnS, CdSe/CdS等)等优点,因此在过去的十几年中被广泛而深入地研究。本文重点综述了在有机体系中,单分散、高荧光性能II–VI族量子点的制备方法——高温热解法及其合成机理的研究进展,并对今后的研究方向作了展望。 相似文献
2.
CdSe量子点对雄性泥鳅的毒性效应研究 总被引:1,自引:0,他引:1
量子点(Quantum Dots,QDs),也称纳米微晶体,由于其独特的荧光特性越来越受到研究者的关注.近年来,量子点的生物学毒性效应及其环境影响成为新的研究热点.本文通过活体实验,以雄性泥鳅为模型动物,以腹腔注射为染毒方式,研究了量子点的雌激素干扰效应、毒物动力学行为以及靶器官的氧化应激指标.结果显示,QDs能够显著抑制E2诱导产生的卵黄蛋白原(Vtg)含量,性腺切片的观察结果与其一致.通过游离Cd^2+和其他几种纳米材料的对比实验,认为量子点对Vtg的抑制表达是游离Cd^2+和QDs颗粒对E2的非特异性吸附的共同作用结果.毒物动力学结果表明,腹腔注射1h后,肌肉、骨头、肠、血液和性腺中QDs含量达到最大浓度(Cmax),随后呈降低趋势 而在肝脏和肾脏中,QDs含量呈增加趋势,说明QDs在动物体内的半衰期较长,在体内能够持续存留.通过对靶器官肝脏相关抗氧化酶活性的测定结果发现,量子点由于壳层对Cd^2+的保护,对抗氧化体系影响较小.本实验对量子点毒性的综合评价为其在活体生物学的应用提供了一定的参考. 相似文献
3.
Dr. Jiuxiao Sun B. S. Shengping Zhang Dr. Muneerah Alomar Dr. Areej S. Alqarni M. S. Najla Alotaibi M. S. Badriah Alshahrani Dr. Abeer A. Alghamdi Prof. Zongkui Kou Prof. Wangqiang Shen Prof. Yingquan Chen Prof. Jian Zhang 《Chemical record (New York, N.Y.)》2023,23(6):e202200268
Quantum dots (QDs) with ultrahigh surface-to-volume ratio, abundant edge active sites, forceful quantum confinement and other remarkable physio-chemical properties, have garnered considerable research interest. MXene QDs, as an emerging member of them, have also attracted wide attention in the last six years, and shown great achievements in many fields. This critical review systematically summarizes the various methods for synthesizing MXene QDs. The characteristics and corresponding applications of various MXene QDs are also presented. The advantages and disadvantages of various synthetic methods, and the limitations of corresponding MXene QDs are compared and highlighted. Finally, the challenges and perspectives of synthesizing MXene QDs are proposed. We hope this review will enlighten researchers to the fabrication of more advancing and promising MXene-based QDs with proprietary properties in diverse applications. 相似文献
4.
Xuanyu Li Menglei Zha Yaxi Li Dr. Jen-Shyang Ni Tianliang Min Dr. Tianyi Kang Dr. Guang Yang Dr. Hao Tang Prof. Kai Li Prof. Xingyu Jiang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22083-22087
A robust platform is developed to assemble sub-10 nm organic aggregation-induced emission (AIE) particles using four different AIE luminogens (AIEgens) with emissions from green to the second near-infrared window (NIR-II). They are called AIE quantum dots (QDs) to distinguish from typical AIE dots which are larger than 25 nm. Compared with AIE dots that are larger than 25 nm, AIE QDs allow more efficient cellular uptake and imaging without surface modification of any membrane-penetrating peptides or other targeting molecules. NIR-II AIEgens, which have nearly no background fluorescence from organisms, are used to demonstrate that AIE QDs can achieve high contrast at the tumor as small as 80 mm3 and evade the liver more efficiently than AIE dots. AIE QDs hold a good promise for sensitive and precise diagnosis of the latent solid tumor in clinical medicine with much lower off-targeting to the liver than AIE dots. 相似文献
5.
HongCheng Li WenRu Luo Yong Tao Yuan Wu XueFei Lv QunFang Zhou GuiBin Jiang 《中国科学B辑(英文版)》2009,52(10):1683-1690
Quantum dots (QDs) have more and more attention as a novel example of nanocrystals due to their unique fluorescent characteristics.
Recently, the toxicity and the potential environmental effects of QDs have become a research hotspot. In this work, in vivo endocrine disrupting effect, toxicokinetics and oxidative stress of QDs were characterized following the intraperitoneal
dosing in Chinese loaches. Vitellogenin (Vtg) levels induced by E2 decreased significantly when administrated with the mixture
of QDs and E2, which was consistent with the observations of histopathology in testes. The release of free Cd2+ from QDs and the non-specific adsorption of E2 by QDs might be the joint factors contributing to the inhibition of Vtg expression
induced by E2 in the male Chinese loaches. In the muscle, bone, intestines, blood and testis, CdSe QDs reached the maximal
concentration (C
max) in approximately 1-h postinjection and subsequently presented downtrend with the prolonged time. Whereas, there were even
increasing tendencies of CdSe QDs’ concentrations in the liver and kidney. It is educible that CdSe QDs can be persistent
at least for 7 days, indicating the overall half-life of CdSe QDs in the fish body is very long. The measurement of hepatic
superoxide dismutase (SOD) activity and reduced glutathione (GSH) content indicate that QDs have smaller effects on the antioxidative
system of the organisms compared with free Cd2+ due to the effective prevention of the release of Cd by PEG coating of QDs. The comprehensive evaluation of QDs’ toxicity
in the present study provides an essential and general framework towards more focused research on the elucidation of the biological
effects of QDs in vivo. 相似文献
6.
Quantum dots (QDs) have shown great potential to provide spatial, temporal, and structural information for biological systems. However, blinking, photobleaching, and spectral blueshift are adverse effects on their practical applications in biomedical research. An investigation of the effects of six reducing agents including cysteine (Cys), 1,4‐dithiothreitol (DTT), ethyl gallate (EG), L ‐glutathione (GSH), mercaptoacetic acid (MAA), and thiourea (TU) on the photostability of single QDs was studied. Our experiments demonstrate that both DTT and EG effectively inhibit blinking, photobleaching, and spectral blueshift. GSH molecules block blinking and photobleaching of QDs. The other reagents, Cys, MAA, and TU, only have the ability to counteract blinking. Possible explanations are given on the basis of research evidence. The results suggest possibilities for significant improvements in QDs for biological applications by adjusting the environmental conditions. 相似文献
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水溶性量子点的制备及应用 总被引:14,自引:0,他引:14
高量子产率的水溶性量子点在众多领域如发光晶体、薄膜光激发器件,尤其是生物荧光标记中展现出巨大的潜在应用价值.量子点荧光明亮、稳定,激发光谱宽,发射光谱窄,且发射波长可通过改变材料的粒径大小和组成来调控,因而在生物样本尤其是活组织的多色成像中极为有用,能有效避免因样本自身发光和光散射导致的信号干扰.量子点的研究已成为一门新兴的交叉科学,是目前最有吸引力的研究领域之一.近年来,水溶性量子点作生物荧光标记物的研究取得了长足的进展.本文简述了量子点的结构特征及光学特性,重点综述了水溶性量子点的制备方法及应用研究进展,特别是它在生物、医学中作荧光探针的最新研究. 相似文献
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Electronic structure plays an important role in determining the physiochemical properties of semiconductor quantum dots (QDs). Fabrication of high-performance QD devices relies on the reliable determination of electronic structure of QDs. Voltammetry enables the easily accessible detection on the energy levels of QDs. Herein, the fundamentals of voltammetric detection are first reviewed and discussed. Since the common ways used for tailoring electronic structure of QDs include tuning size, surface engineering, and varying composition, we next summarize the recent research on using voltammetry for probing the energy levels when studying these three effects. 相似文献
11.
Anthony J. Tavares Lori Chong Eleonora Petryayeva W. Russ Algar Ulrich J. Krull 《Analytical and bioanalytical chemistry》2011,399(7):2331-2342
Quantum dots (QDs) have shown promise as imaging agents in cancer, heart disease, and gene therapy research. This review focuses
on the design of QDs, and modification using peptides and proteins for mediated targeting of tissues for fluorescence imaging
of tumors in vivo. Recent examples from the literature are used to illustrate the potential of QDs as effective imaging agents.
The distribution and ultimate fate of QDs in vivo is considered, and considerations of designs that minimize potential toxicity
are presented. 相似文献
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13.
QDs (Semiconductor QDs, CDs, SiQDs, and Pdots) are used in imaging microorganisms including viruses, bacteria, and fungi. 相似文献
14.
《Analytical letters》2012,45(8):1497-1520
Abstract The optical properties of quantum dots (QDs) have made them attractive materials in diverse fields of application. Since water‐soluble derivatives were obtained, quantum dots have attracted intensive research interest in sensing, diagnosis, imaging, and optical tracking. The analytes that have been targeted span ions, small chemical molecules, proteins, nucleic acids, and cells. The fluorescence of functionalized QDs can be quenched, enhanced, or even ‘switch’ on and off in different cases. However, the mechanisms behind these various responses are not yet all fully understood. This review gives an overview of the emerging use of QDs in analysis. Typical examples, in particular in relation to the discussion on mechanisms are highlighted. 相似文献
15.
Lu Wang Xiaoming Li Yuping Han Ting Wang Yun Zhao Aldalbahi Ali Nahed Nasser El-Sayed Jiye Shi Wenfeng Wang Chunhai Fan Nan Chen 《中国科学:化学(英文版)》2016,59(11):1486-1491
Autophagy is a basic cellular process that decomposes damaged organelles and aberrant proteins. Dysregulation of autophagy is implicated in pathogenesis of neurodegenerative disorders, including Parkinson's disease(PD). Pharmacological compounds that stimulate autophagy can provide neuroprotection in models of PD. Nanoparticles have emerged as regulators of autophagy and have been tested in adjuvant therapy for diseases. In this present study, we explore the effects of quantum dots(QDs) that can induce autophagy in a cellular model of Parkinson's disease. Cd Te/Cd S/Zn S QDs protect differentiated rat pheochromocytoma PC12 cells from MPP+-induced cell damage, including reduced viability, apoptosis and accumulation of α-Synuclein, a characteristic protein of PD. The protective function of QDs is autophagy-dependent. In addition, we investigate the interaction between quantum dots and autophagic pathways and identify beclin1 as an essential factor for QDs-induced autophagy. Our results reveal new promise of QDs in the theranostic of neurodegenerative diseases. 相似文献
16.
量子点在生物化学分析中的应用 总被引:1,自引:0,他引:1
量子点(quantumdots,QDs)由于其优异的光学和电学特性,作为新型的荧光试剂探针对生物大分子进行标记,成为近年来迅速发展的纳米材料在生化分析领域的重要应用之一。文章简述了量子点的基本特性,对制备和修饰量子点的各种方法进行比较总结,重点阐述量子点在生物化学分析中的新进展,尤其是对生物大分子的识别和标记作了详细的总结,并提出研究中存在的一些待解决的问题以及今后量子点的研究方向。 相似文献
17.
本文在水热法合成水溶性CdTe及核壳结构CdTe/CdS量子点的基础上,分别研究了细胞色素c对CdTe量子点及CdTe/CdS核壳量子点荧光的猝灭效应和CdTe量子点对牛血清白蛋白荧光的猝灭效应,并阐述了猝灭机理。结果显示,细胞色素c对CdTe量子点的荧光猝灭效应具有一定的粒径依赖性,粒径越小,猝灭效应越强;细胞色素c对CdTe/CdS核壳量子点的猝灭效应比对CdTe量子点的更强,揭示了受激电子的表面传递机理。CdTe量子点通过松散牛血清白蛋白的螺旋结构而猝灭其荧光。 相似文献
18.
Guodong Sui Jhony Orbulescu Xiaojun Ji Kerim M. Gattás-Asfura Roger M. Leblanc Miodrag Micic 《Journal of Cluster Science》2003,14(2):123-133
Since luminescent CdSe quantum dots (QDs) have shown great potential in biological labeling, the surface chemistry behavior of QDs at interfaces is of great research interest. In the present study, CdSe QDs with green luminescence were modified with hydrophobic chains of varying lengths [from C6 to C18]. These modified QDs can be utilized to form stable monolayers at the air/water interface. Surface pressure-area isotherms of modified QDs have been measured and limiting molecular areas have also been extrapolated in order to analyze the size of the QDs. UV absorption spectra of modified QDs at various surface pressures were also determined. Surface chemistry, as well as the topographic properties, of modified QDs in Langmuir and L-B films was discussed. 相似文献
19.
Quantum dots (QDs) are inorganic semiconductor nanocrystals that have unique optoelectronic properties responsible for bringing
together multidisciplinary research to impel their potential bioanalytical applications. In recent years, the many remarkable
optical properties of QDs have been combined with the ability to make them increasingly biocompatible and specific to the
target. With this great development, QDs hold particular promise as the next generation of fluorescent probes. This review
describes the developments in functionalizing QDs making use of different bioconjugation and capping approaches. The progress
offered by QDs is evidenced by examples on QD-based biosensing, biolabeling, and delivery of therapeutic agents. In the near
future, QD technology still faces some challenges towards the envisioned broad bioanalytical purposes.
相似文献
20.
Tuning Optical Properties and Photocatalytic Activities of Carbon‐based “Quantum Dots” Through their Surface Groups 下载免费PDF全文
Shengliang Hu 《Chemical record (New York, N.Y.)》2016,16(1):219-230
We report recent progress in tuning optical properties and photocatalytic activities of carbon‐based quantum dots (carbon‐based QDs) through their surface groups. It is increasingly clear that the properties of carbon‐based QDs are more dependent on their surface groups than on their size. The present challenge remains as to how to control the type, number, and conformation of the heterogeneous groups on the surface of carbon‐based QDs when considering their target applications. By reviewing the related achievements, this personal account aims to help us understand the roles different surface groups play in tuning the properties of carbon‐based QDs. A number of significant accomplishments have demonstrated that surface groups possess strong power in engineering electronic structure and controlling photogenerated charge behaviors of carbon‐based QDs. However, effective strategies for modifying carbon‐based QDs with diverse heterogeneous groups are still needed. 相似文献