AULA 7: PONTOS QUANTICOS(Quantum Dots): SINTESE E APLICAÇÃO Prof. Dr. Nelson Durán IQ-UNICAMP...

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AULA 7: PONTOS QUANTICOS(Quantum Dots):SINTESE E APLICAÇÃO

Prof. Dr. Nelson DuránIQ-UNICAMPCURSO QF-435-SEGUNDO SEMENTRE 2008NANOMATERIAIS

UM EXEMPLO DA DEPENDENCIA DO TAMANHO

NANOPARTICULAS METALICAS--------------------------------------------------------------------------------------------------

Chiral highly luminescent CdS quantum dots. M.P. Moloney, Y.K. Gunko and John M. Kell. Chem. Commun., 2007, 3900–3902

CD monitoring: (A) L-Penicillamine pH 11; (B) after additionCd salt; (C) Afrer thioacetamide and (D) after microwavetreatment

In conclusion, it was prepared strongly emitting chiral D-Pen and L-Pen capped CdS QDs. Using CD spectroscopy and have shown that they are optically active and possess almost identical mirror images of one another in the range of 200–390 nm. Its believe that these QDs could find important applications, includingtheir use as fluorescent chemical and biochemical chirality sensorsand molecular recognition nanodevices. In addition they might have potential for some biomedical uses. For example, it is known that certain proteins and drugs only show activity to one enantiomer,(e.g. the transactivator protein of type-1 human immunodeficiency virus shows a preference for D- over L-penicillamine).

a,b, Quantum dots having different molecules for target-specific interaction, and, attached to the surface, paramagnetic lipids; the molecules are shown attached to part of the dot for clarity, but extend over the whole surface) and chelators for nuclear-spin labelling. c, Based on the description the silica sphere has QDs and paramagnetic nanoparticles inside and target-specific groups attached to the outside. d, The structure of a multimodal QD probe, based on silica-shelled single-QD micelles.

Rumiana Bakalova, Zhivko Zhelev, Ichio Aoki & Iwao

KannoNature Photonics 1, 487 - 489

(2007)

In Vivo Imaging of Quantum Dots Encapsulated in Phospholipid MicellesB. Dubertret, P. Skourides, D.J. Norris, V. Noireaux, A.H. Brivanlou, A. Libchaber. SCIENCE 298, 1759 (2002)

These results indicate that micelle-encapsulated QDs fulfill the promise of fluorescent semiconductor nanocrystals for both in vitro and in vivo studies. Compared to other systems,they simultaneously provide efficient fluorescence, a great reduction in photobleaching, colloidal stability in a variety of bioenvironments, and low nonspecific adsorption.

Nanoscale Biosensors Based on Luminescent Quantum Dots.H. Mattoussi and E.R. Goldmanhttp://www.nrl.navy.mil/nanoscience/files/nanooptics_poster2.pdf

FLUORESCENCERESONANCE ENERGY TRANSFER (FRET)

(recompensa)

DESIGN OF QD NANOSCALE TNT SENSOR BASED ON FLUORESCENCERESONANCE ENERGY TRANSFER (FRET)

http://e-fisica.fc.up.pt/2006/Actividades/Palestras/nanomateriais.pdf

Porto , FCUP-INESC- 2006-Portugal