查看完整版本: A. P. Alivisatos教授S&N文章汇编

钴纳米粒子形貌控制性合成的重大突破!!

[size=5]Colloidal Nanocrystal Shape and Size Control: The Case of Cobalt[/size]

Victor F. Puntes,1* Kannan M. Krishnan,2 A. Paul Alivisatos1*

Weshow that a relatively simple approach for controlling the colloidal synthesis of anisotropic cadmium selenide semiconductor nanorods can be extended to the size-controlled preparation of magnetic cobalt nanorods as well as spherically shaped nanocrystals. This approach helps deÞne a minimum feature set needed to separately control the sizes and shapes of nanocrystals. The resulting cobalt nanocrystals produce interesting two- and three-dimensional superstructures, including ribbons of nanorods.


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下面要介绍的一篇文章是半导体荧光纳米粒子在生物学中应用的开山之作.我不做详细说明,相信大家已经能够耳熟能详,所附图片已经成为这一领域的经典.
值得提出的在同期Science本文之后文章即为著名华人科学家Shuming Nie的大作.据Shu本人介绍,之所以他的文章在后面,是因为相对于Alivisetos的文章投稿时间相差一周,结果在后来的文章引用方面有近100次的差距(据本人最近查阅Alivisetos' paper: 1526; Nie's paper: 1439),看来在科学研究方面时间是多么宝贵.


[size=5]Semiconductor Nanocrystals as Fluorescent Biological Labels[/size]

Marcel Bruchez Jr., Mario Moronne, Peter Gin, Shimon Weiss,* A. Paul Alivisatos*

Semiconductor nanocrystals were prepared for use as ßuorescent probes in biological staining and diagnostics. Compared with conventional ßuorophores, the nanocrystals have a narrow, tunable, symmetric emission spectrum and are photochemically stable. The advantages of the broad, continuous excitation spectrum were demonstrated in a dual-emission, single-excitation labeling experiment on mouse Þbroblasts. These nanocrystal probes are thus complementary and in some cases may be superior to existing ßuorophores.

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支持搂住的工作
:lol

谢谢分享！！！！！

传呢！
我等着看呢

好东东，仔细瞧瞧:victory:

:lol ，谢谢分享，:victory:

谢谢分享，楼主加油:victory: :victory: :victory:

:victory: :victory:

回复 #1 rabbithong 的帖子

与大家一起共建纳米科技世界论坛，分享纳米科技的新资料，资源。帮助你解决与纳米科技学习和科研有关的实际问题。如你有问题，困难和想分享什么，请加入我们，共建这个社区。团结就是力量！

回复 #1 rabbithong 的帖子

与大家一起共建纳米科技世界论坛，分享纳米科技的新资料，资源。帮助你解决与纳米科技学习和科研有关的实际问题。如你有问题，困难和想分享什么，请加入我们，共建这个社区。团结就是力量！

[size=5]A single-electron transistor made from a cadmium selenide nanocrystal[/size]

David L. Klein1,2, Richard Roth2,3, Andrew K. L. Lim2,3, A. Paul Alivisatos2,3 and Paul L. McEuen1,3

Department of Physics, University of California, Berkeley, California 94720, USA
Department of Chemistry, University of California, Berkeley, California 94720, USA
Molecular Design Institute, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
Correspondence to: Paul L. McEuen1,3 Correspondence and requests for materials should be addressed to P.L.M. (e-mail: Email: [email]mceuen@physics.berkekely.edu[/email]).


Top of pageAbstractThe techniques of colloidal chemistry permit the routine creation of semiconductor nanocrystals whose dimensions are much smaller than those that can be realized using lithographic techniques. The sizes of such nanocrystals can be varied systematically to study quantum size effects or to make novel electronic or optical materials with tailored properties. Preliminary studies of both the electrical and optical properties of individual nanocrystals have been performed recently. These studies show clearly that a single excess charge on a nanocrystal can markedly influence its properties. Here we present measurements of electrical transport in a single-electron transistor made from a colloidal nanocrystal of cadmium selenide. This device structure enables the number of charge carriers on the nanocrystal to be tuned directly, and so permits the measurement of the energy required for adding successive charge carriers. Such measurements are invaluable in understanding the energy-level spectra of small electronic systems, as has been shown by similar studies of lithographically patterned quantum dots and small metallic grains.

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[[i] 本帖最后由 rabbithong 于 2007-08-21 17:49 编辑 [/i]]

[size=5]A molecular ruler based on plasmon coupling of single gold and silver nanoparticles[/size]

Carsten Sönnichsen1, 3, Björn M Reinhard2, 3, Jan Liphardt2 & A Paul Alivisatos1
1  Department of Chemistry, University of California, Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
2  Department of Physics, University of California, Berkeley and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
3  These authors contributed equally to this work.
Correspondence should be addressed to Jan Liphardt [email]Liphardt@physics.berkeley.edu[/email] or A Paul Alivisatos [email]alivis@berkeley.edu[/email]


Förster Resonance Energy Transfer has served as a molecular ruler that reports conformational changes and intramolecular distances of single biomolecules. However, such rulers suffer from low and fluctuating signal intensities, limited observation time due to photobleaching, and an upper distance limit of 10 nm. Noble metal nanoparticles have plasmon resonances in the visible range and do not blink or bleach. They have been employed as alternative probes to overcome the limitations of organic fluorophores, and the coupling of plasmons in nearby particles has been exploited to detect particle aggregation by a distinct color change in bulk experiments. Here we demonstrate that plasmon coupling can be used to monitor distances between single pairs of gold and silver nanoparticles. We followed the directed assembly of gold and silver nanoparticle dimers in real time and studied the kinetics of single DNA hybridization events. These 'plasmon rulers' allowed us to continuously monitor separations of up to 70 nm for >3,000 s.

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[[i] 本帖最后由 rabbithong 于 2007-08-21 17:59 编辑 [/i]]

[size=5]The use of nanocrystals in biological detection[/size]

Paul Alivisatos
University of California-Berkeley, Department of Chemistry, B60 Hildebrand Hall, Berkeley, California 94720-1460, USA. [email]alivis@uclink4.berkeley.edu[/email]

In the coming decade, the ability to sense and detect the state of biological systems and living organisms optically, electrically and magnetically will be radically transformed by developments in materials physics and chemistry. The emerging ability to control the patterns of matter on the nanometer length scale can be expected to lead to entirely new types of biological sensors. These new systems will be capable of sensing at the single-molecule level in living cells, and capable of parallel integration for detection of multiple signals, enabling a diversity of simultaneous experiments, as well as better crosschecks and controls.


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[size=5]Collective behaviour in two-dimensional cobalt nanoparticle assemblies observed by magnetic force microscopy[/size]

Victor F. Puntes1, Pau Gorostiza2, Deborah M. Aruguete3, Neus G. Bastus1 and A. Paul Alivisatos3


AbstractThe use of magnetic nanoparticles in the development of ultra-high-density recording media is the subject of intense research. Much of the attention of this research is devoted to the stability of magnetic moments, often neglecting the influence of dipolar interactions. Here, we explore the magnetic microstructure of different assemblies of monodisperse cobalt single-domain nanoparticles by magnetic force microscopy and magnetometric measurements. We observe that when the density of particles per unit area is higher than a determined threshold, the two-dimensional self-assemblies behave as a continuous ferromagnetic thin film. Correlated areas (similar to domains) of parallel magnetization roughly ten particles in diameter appear. As this magnetic percolation is mediated by dipolar interactions, the magnetic microstructure, its distribution and stability, is strongly dependent on the topological distribution of the dipoles. Thus, the magnetic structures of three-dimensional assemblies are magnetically soft, and an evolution of the magnetic microstructure is observed with consecutive scans of the microscope tip.


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thanks for sharing

经典 这个论坛真好啊。。。

好专题，多多学习！

支持楼主:lol

多谢分享:victory: :victory: