共查询到20条相似文献,搜索用时 15 毫秒
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用于生物标记的半导体量子点研究 总被引:1,自引:0,他引:1
半导体量子点的独特光学性质使之成为理想的荧光探针材料,在生物医学领域具有广阔的应用前景.本文评述了目前量子点合成、表面修饰、结合生物分子的方法,以及半导体量子点在生物标记应用中相对于传统有机染料的优点. 相似文献
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Raquel Ibá?ez-Peral Peter L. Bergquist Malcolm R. Walter Moreland Gibbs Ewa M. Goldys Belinda Ferrari 《International journal of molecular sciences》2008,9(12):2622-2638
QDs may offer significant advantages in environmental and bead-based applications where the target cells need to be discriminated above background fluorescence. We have examined the possible applications of QDs for flow cytometric measurements (FCM) by studying their excitation - emission spectra and their binding to paramagnetic beads. We labelled beads with either QDs or a commonly-used fluorochrome (FITC) and studied their fluorescence intensity by FCM. Flow cytometric comparisons indicated that the minimum fluorophore concentration required for detection of QDs above autofluorescent background was 100-fold less than for FITC. 相似文献
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Huaipeng Su Hengyi Xu Shuai Gao John David Dixon Zoraida P. Aguilar Andrew Y. Wang Jian Xu Jingkang Wang 《Nanoscale research letters》2010,5(3):625-630
We report in this article the microwave synthesis of relatively monodisperse, highly crystalline CdSe quantum dots (QDs) overcoated
with Cd0.5Zn0.5S/ZnS multishells. The as-prepared QDs exhibited narrow photoluminescence bandwidth as the consequence of homogeneous size
distribution and uniform crystallinity, which was confirmed by transmission electron microscopy. A high photoluminescence
quantum yield up to 80% was measured for the core/multishell nanocrystals. Finally, the resulting CdSe/Cd0.5Zn0.5S/ZnS core/multishell QDs have been successfully applied to the labeling and imaging of breast cancer cells (SK-BR3). 相似文献
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用巯基丙酸作为稳定剂,在水相中合成了CdS量子点。基于Cu^2+对CdS量子点有显著的荧光猝灭作用,建立了检测水相中微量Cu^2+的新方法。研究结果表明,在弱碱性的水溶液中,当Cu^2+的浓度在1×10^-5-3×10^-4 mol·L^-1之间时,量子点的荧光猝灭强度△F/F与Cu^2+的浓度之间很好地符合Stern-Volmer线性方程,线性相关系数为0.9952。方法的检出限为5.85×10^-6 mol·L^-1,相对标准偏差为3.75%,加标回收率为95.5%-118.5%。讨论了量子点的荧光猝灭机理。在研究金属离子和一些化合物的干扰作用时,发现有的物质使量子点的荧光猝灭,有的物质却使量子点的荧光强度增强,发光强度对不同的物质就具有选择性。选择合适的掩蔽剂可以消除较强的离子干扰。 相似文献
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石墨烯量子点具有许多吸引人的优点,如低细胞毒性、溶解能力强、稳定的光致发光、良好的生物相容性、高比表面积、电子高迁移率和可调节带隙等,因此,适用于构建传感系统和生物成像。根据近几年来,基于石墨烯量子点性质构建的光学生物传感器和电化学生物传感器以及石墨烯量子点在生物成像技术中的应用进行了综述。 相似文献
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介绍了基于量子点(QDs)的FRET原理,综述了基于QDs的FRET在生物传感器、蛋白质相互作用、生物分子构像变化和癌症治疗的光敏剂研究中的应用. 相似文献
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Mariya Borovaya Inna Horiunova Svitlana Plokhovska Nadia Pushkarova Yaroslav Blume Alla Yemets 《International journal of molecular sciences》2021,22(22)
Ag-based quantum dots (QDs) are semiconductor nanomaterials with exclusive electrooptical properties ideally adaptable for various biotechnological, chemical, and medical applications. Silver-based semiconductor nanocrystals have developed rapidly over the past decades. They have become a promising luminescent functional material for in vivo and in vitro fluorescent studies due to their ability to emit at the near-infrared (NIR) wavelength. In this review, we discuss the basic features of Ag-based QDs, the current status of classic (chemical) and novel methods (“green” synthesis) used to produce these QDs. Additionally, the advantages of using such organisms as bacteria, actinomycetes, fungi, algae, and plants for silver-based QDs biosynthesis have been discussed. The application of silver-based QDs as fluorophores for bioimaging application due to their fluorescence intensity, high quantum yield, fluorescent stability, and resistance to photobleaching has also been reviewed. 相似文献
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Pavlina Sobrova Marketa Ryvolova Jaromir Hubalek Vojtech Adam Rene Kizek 《International journal of molecular sciences》2013,14(7):13497-13510
Electrochemical detection of quantum dots (QDs) has already been used in numerous applications. However, QDs have not been well characterized using voltammetry, with respect to their characterization and quantification. Therefore, the main aim was to characterize CdTe QDs using cyclic and differential pulse voltammetry. The obtained peaks were identified and the detection limit (3 S/N) was estimated down to 100 fg/mL. Based on the convincing results, a new method for how to study stability and quantify the dots was suggested. Thus, the approach was further utilized for the testing of QDs stability. 相似文献
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Dr. Yun Deng Aifei Xu Dr. Yanhua Yu Cheng Fu Prof. Gaolin Liang 《Chembiochem : a European journal of chemical biology》2019,20(4):499-510
Molecular imaging plays a critical role in biomedical research. The combination of different modalities can generate complementary information and provide synergistic advantages over single modality alone. Noninvasive and nonradioactive fluorescent imaging (FI)/magnetic resonance imaging (MRI) dualmodality probes fuse the high sensitivity of FI and the high temporal and spatial resolution and deep-tissue penetration of MRI, and their increasing applications have been reported in biomedical research and clinical practices, including cell labeling, enzyme activity measurement, tumor diagnosis and therapy, and anatomical localization and real-time assessment during surgery. 相似文献
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以水热法在水相中直接合成了巯基乙酸修饰的CdSe量子点,并将合成的CdSe量子点进行表征、纯化。在波长365nm紫外光的激发下,CdSe量子点发射出明亮的黄绿色荧光,荧光发射峰约位于528nm,将得到的CdSe量子点纳米发光材料应用于非渗透性客体上潜指纹的荧光标记成像研究,发现CdSe量子点溶液显现的手印纹线流畅,显现细节特征明显,呈现明亮的黄绿色荧光指纹,具有很高的实用价值和鉴定价值。 相似文献
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Xiaogang Chen Liang Li Yongxian Lai Jianna Yan Yichen Tang Xiuli Wang 《International journal of molecular sciences》2015,16(5):11500-11508
These glutathione (GSH)-conjugated CdTe/CdSe core/shell quantum dot (QD) nanoparticles in aqueous solution were synthesized using a microwave-assisted approach. The prepared type II core/shell QD nanoparticles were characterized by UV–Vis absorption, photoluminescence (PL) spectroscopy, X-ray powder diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM). Results revealed that the QD nanoparticles exhibited good dispersity, a uniform size distribution and tunable fluorescence emission in the near-infrared (NIR) region. In addition, these nanoparticles exhibited good biocompatibility and photoluminescence in cell imaging. In particular, this type of core/shell NIR QDs may have potential applications in molecular imaging. 相似文献
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Small-molecule fluorescent probes for hypochlorous acid (HOCl), one of the poorly understood reactive oxygen species (ROS), help to unveil HOCl functions in health and disease. Numerous small-molecule HOCl fluorescent probes have been developed in the past decade. Nevertheless, only a portion of them demonstrated their practical applications in biomedical research because of common problems in selectivity, sensitivity, chemostability, and photostability, etc. The problems could be addressed by a combination of rational probe design and careful selection of fluorophore templates. In this review, we describe several classes of representative HOCl fluorescent probes based on their fluorophore templates, and we discuss their design strategies, photophysical properties, and biological applications. A comprehension of their strengths, weaknesses, and common uses will facilitate the development of ideal HOCl assays and the discovery of novel biological processes. 相似文献
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Chuanxin Zhai Hui Zhang Ning Du Bingdi Chen Hai Huang Yulian Wu Deren Yang 《Nanoscale research letters》2011,6(1):31
We developed a novel one-pot polyol approach for the synthesis of biocompatible CdSe quantum dots (QDs) using poly(acrylic
acid) (PAA) as a capping ligand at 240°C. The morphological and structural characterization confirmed the formation of biocompatible
and monodisperse CdSe QDs with several nanometers in size. The encapsulation of CdS thin layers on the surface of CdSe QDs
(CdSe/CdS core–shell QDs) was used for passivating the defect emission (650 nm) and enhancing the fluorescent quantum yields
up to 30% of band-to-band emission (530–600 nm). Moreover, the PL emission peak of CdSe/CdS core–shell QDs could be tuned
from 530 to 600 nm by the size of CdSe core. The as-prepared CdSe/CdS core–shell QDs with small size, well water solubility,
good monodispersity, and bright PL emission showed high performance as fluorescent cell labels in vitro. The viability of
QDs-labeled 293T cells was evaluated using a 3-(4,5-dimethylthiazol)-2-diphenyltertrazolium bromide (MTT) assay. The results
showed the satisfactory (>80%) biocompatibility of as-synthesized PAA-capped QDs at the Cd concentration of 15 μg/ml. 相似文献
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Dr. Cindy Y. Jao Dr. Daniel Nedelcu Dr. Lyle V. Lopez Dr. Thilani N. Samarakoon Prof. Dr. Ruth Welti Prof. Dr. Adrian Salic 《Chembiochem : a European journal of chemical biology》2015,16(4):611-617
Cholesterol is a fundamental lipid component of eukaryotic membranes and a precursor of potent signaling molecules, such as oxysterols and steroid hormones. Cholesterol and oxysterols are also essential for Hedgehog signaling, a pathway critical in embryogenesis and cancer. Despite their importance, the use of imaging sterols in cells is currently very limited. We introduce a robust and versatile method for sterol microscopy based on C19 alkyne cholesterol and oxysterol analogues. These sterol analogues are fully functional; they rescue growth of cholesterol auxotrophic cells and faithfully recapitulate the multiple roles that sterols play in Hedgehog signal transduction. Alkyne sterol analogues incorporate efficiently into cellular membranes and can be imaged with high resolution after copper(I)‐catalyzed azide–alkyne cycloaddition reaction with fluorescent azides. We demonstrate the use of alkyne sterol probes for visualizing the subcellular distribution of cholesterol and for two‐color imaging of sterols and choline phospholipids. Our imaging strategy should be broadly applicable to studying the role of sterols in normal physiology and disease. 相似文献
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We theoretically propose a double quantum dots (QDs) ring to filter the electron spin that works due to the Rashba spin–orbit
interaction (RSOI) existing inside the QDs, the spin-dependent inter-dot tunneling coupling and the magnetic flux penetrating
through the ring. By varying the RSOI-induced phase factor, the magnetic flux and the strength of the spin-dependent inter-dot
tunneling coupling, which arises from a constant magnetic field applied on the tunneling junction between the QDs, a 100%
spin-polarized conductance can be obtained. We show that both the spin orientations and the magnitude of it can be controlled
by adjusting the above-mentioned parameters. The spin filtering effect is robust even in the presence of strong intra-dot
Coulomb interactions and arbitrary dot-lead coupling configurations. 相似文献