@article {1662,
	title = {Systems and Methods for Forming Nitrogen-Based Compounds},
	year = {2020},
	author = {Nazemi, M. and El-Sayed, M.A.}
}
@article {1634,
	title = {Single-Crystal Electrospun Plasmonic Perovskite Nanofibers},
	journal = {The Journal of Physical Chemistry C},
	year = {2018},
	author = {A.M. Abdellah and A. Hafez and Panikkanvalappil, S. R. and El-Sayed, M. A. and Allam, N. K.}
}
@article {1610,
	title = {Shape tunable plasmonic nanoparticles},
	volume = {9,588,124},
	year = {2017},
	author = {El-Sayed, M. A. and El-Sayed, I H}
}
@article {1585,
	title = {The Sensitivity of the Distance Dependent Plasmonic Coupling between Two Nanocubes to their Orientation: Edge-to-Edge versus Face-to-Face},
	journal = {The Journal of Physical Chemistry C},
	volume = {120},
	year = {2016},
	pages = {4564{\textendash}4570},
	author = {Hooshmand, Nasrin and Bordley, Justin A and El-Sayed, Mostafa A.}
}
@article {1617,
	title = {Simultaneous time-dependent surface-enhanced raman spectroscopy, metabolomics, and proteomics reveal cancer cell death mechanisms associated with gold nanorod photothermal therapy},
	journal = {Journal of the American Chemical Society},
	year = {2016},
	author = {Ali, Moustafa RK and et al.}
}
@article {1576,
	title = {Silver nanocube aggregation gradient materials in search for total internal reflection with high phase sensitivity},
	journal = {Nanoscale},
	volume = {7},
	year = {2015},
	pages = {5230-5239},
	abstract = {We fabricated monolayer coatings of a silver nanocube aggregation to create a step-wise optical strip by applying different surface pressures during slow Langmuir-Blodgett deposition. The varying amount of randomly distributed nanocube aggregates with different surface coverages in gradient manner due to changes in surface pressure allows for continuous control of the polarization sensitive absorption of the incoming light over a broad optical spectrum. Optical characterization under total internal reflection conditions combined with electromagnetic simulations reveal that the broadband light absorption depends on the relative orientation of the nanoparticles to the polarization of the incoming light. By using computer simulations, we found that the electric field vector of the s-polarized light interacts with the different types of silver nanocube aggregations to excite different plasmonic resonances. The s-polarization shows dramatic changes of the plasmonic resonances at different angles of incidence (shift of 64 nm per 10[degree] angle of incidence). With a low surface nanocube coverage (from 5\% to 20\%), we observed a polarization-selective high absorption of 80\% (with an average 75\%) of the incoming light over a broad optical range in the visible region from 400 nm to 700 nm. This large-area gradient material with location-dependent optical properties can be of particular interest for broadband light absorption, phase-sensitive sensors, and imaging.},
	doi = {10.1039/C4NR06430E},
	url = {http://dx.doi.org/10.1039/C4NR06430E},
	author = {Konig, Tobias A. F. and Ledin, Petr A and Russell, Michael and Geldmeier, Jeffrey A and Mahmoud, Mahmoud. A. and El-Sayed, Mostafa A. and Tsukruk, Vladimir V.}
}
@article {1356,
	title = {Self-Assembled Nanostructured Photoanodes with Staggered Bandgap for Efficient Solar Energy Conversion},
	journal = {ACS nano},
	year = {2014},
	isbn = {1936-0851},
	author = {Nashed, Ramy and Szymanski, Paul and El-Sayed, Mostafa A. and Allam, Nageh K}
}
@article {1359,
	title = {Shape- and Symmetry-Dependent Mechanical Properties of Metallic Gold and Silver on the Nanoscale},
	journal = {Nano Letters},
	volume = {14},
	number = {2},
	year = {2014},
	note = {Mahmoud, Mahmoud A. O{\textquoteright}Neil, Daniel El-Sayed, Mostafa A.},
	month = {Feb},
	pages = {743-748},
	isbn = {1530-6984},
	doi = {10.1021/nl4040362},
	author = {Mahmoud, M A and O{\textquoteright}Neil, D. and El-Sayed, M. A.}
}
@article {1364,
	title = {Silver Nanocube Aggregates in Cylindrical Pores for Higher Refractive Index Plasmonic Sensing},
	journal = {Particle \& Particle Systems Characterization},
	volume = {31},
	number = {2},
	year = {2014},
	pages = {274-283},
	isbn = {1521-4117},
	author = {K{\"o}nig, Tobias and Kodiyath, Rajesh and Combs, Zachary A. and Mahmoud, Mahmoud and El-Sayed, Mostafa A and Tsukruk, Vladimir V.}
}
@article {1366,
	title = {The Spectroscopy of Homo and Heterodimers of Silver and Gold Nanocubes as a Function of Separation: a DDA Simulation},
	journal = {The Journal of Physical Chemistry A},
	year = {2014},
	isbn = {1089-5639},
	author = {Hooshmand, Nasrin and O{\textquoteright}Neil, Daniel and Asiri, Abdullah M and El-Sayed, Mostafa A.}
}
@article {1357,
	title = {Stacked Gold Nanorectangles with Higher Order Plasmonic Modes and Top-Down Plasmonic Coupling},
	journal = {The Journal of Physical Chemistry C},
	volume = {118},
	number = {10},
	year = {2014},
	pages = {5453-5462},
	isbn = {1932-7447},
	author = {Malak, Sidney T. and König, Tobias and Near, Rachel and Combs, Zachary A. and El-Sayed, Mostafa A. and Tsukruk, Vladimir V.}
}
@article {1390,
	title = {Substrate Effect on the Plasmonic Sensing Ability of Hollow Nanoparticles of Different Shapes},
	journal = {Journal of Physical Chemistry B},
	volume = {117},
	number = {16},
	year = {2013},
	note = {Mahmoud, Mahmoud A. El-Sayed, Mostafa A.Si},
	month = {Apr},
	pages = {4468-4477},
	isbn = {1520-6106},
	doi = {10.1021/jp3085793},
	author = {Mahmoud, M A and El-Sayed, M. A.}
}
@article {1348,
	title = {Surface Assembly and Plasmonic Properties in Strongly Coupled Segmented Gold Nanorods},
	journal = {Small},
	year = {2013},
	note = {MEDLINE AN 2013463112(Journal; Article; (JOURNAL ARTICLE))},
	month = {//},
	abstract = {An assembly strategy is reported such that segmented nanorods fabricated through template-assisted methods can be robustly transferred and tethered to a pre-functionalized substrate with excellent uniformity over large surface areas. After embedding the rods, sacrificial nickel segments were selectively etched leaving behind strongly coupled segmented gold nanorods with gaps between rods below 40 nm and as small as 2 nm. Hyper-spectral imaging is utilized to measure Rayleigh scattering spectra from individual and coupled nanorod elements in contrast to common bulk measurements. This approach discerns the effects of not only changing segment and gap size but also the presence of characteristic defects on the plasmonic coupling between closely spaced nanorods. Polarized hyper-spectral measurements are conducted to provide direct observation of the anisotropic plasmonic resonance modes in individual and coupled nanorods, which are close to those predicted by computer simulations for nanorods with ideal shapes. Some common deviations from ideal shape such as non-flat facets and asymmetric tails are demonstrated to result in the appearance of characteristic plasmon resonances, which have not been considered before. The large-scale assembly of coupled noble nanostructures with fine control over geometry and high uniformity provides means to strongly tune the scattering, absorption, and near-field plasmonic properties through the geometric arrangement of precisely controlled nanorod segments.[on SciFinder (R)]},
	isbn = {1613-6829},
	author = {Gupta, Maneesh K. and Konig, Tobias and Near, Rachel and Nepal, Dhriti and Drummy, Lawrence F. and Biswas, Sushmita and Naik, Swati and Vaia, Richard A. and El-Sayed, Mostafa A. and Tsukruk, Vladimir V.}
}
@article {1378,
	title = {Surface-Enhanced Raman Spectroscopy for Real-Time Monitoring of Reactive Oxygen Species-Induced DNA Damage and Its Prevention by Platinum Nanoparticles},
	journal = {Acs Nano},
	volume = {7},
	number = {9},
	year = {2013},
	note = {Panikkanvalappil, Sajanlal R. Mahmoud, Mahmoud A. Mackey, Megan A. El-Sayed, Mostafa A.},
	month = {Sep},
	pages = {7524-7533},
	isbn = {1936-0851},
	doi = {10.1021/nn403722x},
	author = {Panikkanvalappil, S. R. and Mahmoud, M A and Mackey, M. A. and El-Sayed, M. A.}
}
@article {1327,
	title = {Size matters: gold nanoparticles in targeted cancer drug delivery},
	journal = {Ther. Delivery},
	volume = {3},
	number = {4},
	year = {2012},
	note = {CAPLUS AN 2012:489934(Journal; General Review; Online Computer File)},
	month = {//},
	pages = {457-478},
	publisher = {Future Science Ltd.},
	type = {10.4155/tde.12.21},
	abstract = {A review. Cancer is the current leading cause of death worldwide, responsible for approx. one quarter of all deaths in the USA and UK. Nanotechnologies provide tremendous opportunities for multimodal, site-specific drug delivery to these disease sites and Au nanoparticles further offer a particularly unique set of phys., chem. and photonic properties with which to do so. This review will highlight some recent advances, by our lab. and others, in the use of Au nanoparticles for systemic drug delivery to these malignancies and will also provide insights into their rational design, synthesis, physiol. properties and clin./preclin. applications, as well as strategies and challenges toward the clin. implementation of these constructs moving forward. [on SciFinder(R)]},
	keywords = {review gold nanoparticle targeted cancer drug delivery},
	isbn = {2041-5990},
	doi = {10.4155/tde.12.21},
	author = {Dreaden, Erik C. and Austin, Lauren and Mackey, Megan A. and El-Sayed, Mostafa A.}
}
@article {1330,
	title = {Small Molecule-Gold Nanorod Conjugates Selectively Target and Induce Macrophage Cytotoxicity towards Breast Cancer Cells},
	journal = {Small},
	volume = {8},
	number = {18},
	year = {2012},
	note = {Times Cited: 0Dreaden, Erik C. Mwakwari, Sandra C. Austin, Lauren A. Kieffer, Matthew J. Oyelere, Adegboyega K. El-Sayed, Mostafa A.},
	month = {Sep},
	pages = {2819-2822},
	isbn = {1613-6810},
	doi = {10.1002/smll.201200333},
	author = {Dreaden, E. C. and Mwakwari, S. C. and Austin, Lauren and Kieffer, M. J. and Oyelere, A. K. and El-Sayed, M. A.}
}
@article {1344,
	title = {Some recent developments in photoelectrochemical water splitting using nanostructured TiO2: a short review},
	journal = {Theoretical Chemistry Accounts},
	volume = {131},
	number = {6},
	year = {2012},
	note = {Times Cited: 0Szymanski, Paul El-Sayed, Mostafa A.},
	month = {Jun},
	abstract = {Photoelectrochemical cells with TiO2 electrodes to convert sunlight and water into gaseous hydrogen and oxygen are a source of clean and renewable fuel. Despite their great potential, far-from-ideal performance and poor utilization of the solar spectrum have prevented them from becoming a widespread and practical technology. We review recent experimental work that uses dynamics measurements to study limitations of photoelectrochemical cells from a fundamental level and the use of TiO2 nanotube arrays as a superior alternative to TiO2 nanoparticles. Through a combination of nanoscale size control, doping, composite materials, and the incorporation of noble-metal nanoparticles, improved performance and light harvesting are demonstrated.},
	isbn = {1432-881X},
	doi = {10.1007/s00214-012-1202-2},
	author = {Szymanski, P. and El-Sayed, M. A.}
}
@article {1324,
	title = {Synthesis and Optical Properties of Small Au Nanorods Using a Seedless Growth Technique},
	journal = {Langmuir},
	volume = {28},
	number = {25},
	year = {2012},
	note = {Times Cited: 2Ali, Moustafa R. K. Snyder, Brian El-Sayed, Mostafa A.},
	month = {Jun},
	pages = {9807-9815},
	abstract = {Gold nanoparticles have shown potential in photothermal cancer therapy and optoelectronic technology. In both applications, a call for small size nanorods is warranted. In the present work, a one-pot seedless synthetic technique has been developed to prepare relatively small monodisperse gold nanorods with average dimensions (length x width) of 18 x 4.5 nm, 25 x 5 nm, 15 x 4.5 nm, and 10 x 2.5 nm. In this method, the pH was found to play a crucial role in the monodispersity of the nanorods when the NaBH4 concentration of the growth solution was adjusted to control the reduction rate of the gold ions. At the optimized pH and NaBH4 concentrations, smaller gold nanorods were produced by adjusting the CTAB concentration in the growth solution. In addition, the concentration of silver ions in the growth solution was found to be pivotal in controlling the aspect ratio of the nanorods. The extinction coefficient values for the small gold nanorods synthesized with three different aspect ratios were estimated using the absorption spectra, size distributions, and the atomic spectroscopic analysis data. The previously accepted relationships between the extinction coefficient or the longitudinal band wavelength values and the nanorods{\textquoteright} aspect ratios found for the large nanorods do not extend to the small size domain reported in the present work. The failure of extending these relationships over larger sizes is a result of the interaction of light with the large rods giving an extinction band which results mostly from scattering processes while the extinction of the small nanorods results from absorption processes.},
	isbn = {0743-7463},
	doi = {10.1021/la301387p},
	author = {Ali, M. R. K. and Snyder, B. and El-Sayed, M. A.}
}
@article {1423,
	title = {Synthesis and Optical Properties of Small Au Nanorods Using a Seedless Growth Technique},
	journal = {Langmuir},
	volume = {28},
	year = {2012},
	month = {Jun},
	pages = {9807-9815},
	abstract = {Gold nanoparticles have shown potential in photothermal cancer therapy and optoelectronic technology. In both applications, a call for small size nanorods is warranted. In the present work, a one-pot seedless synthetic technique has been developed to prepare relatively small monodisperse gold nanorods with average dimensions (length x width) of 18 x 4.5 nm, 25 x 5 nm, 15 x 4.5 nm, and 10 x 2.5 nm. In this method, the pH was found to play a crucial role in the monodispersity of the nanorods when the NaBH4 concentration of the growth solution was adjusted to control the reduction rate of the gold ions. At the optimized pH and NaBH4 concentrations, smaller gold nanorods were produced by adjusting the CTAB concentration in the growth solution. In addition, the concentration of silver ions in the growth solution was found to be pivotal in controlling the aspect ratio of the nanorods. The extinction coefficient values for the small gold nanorods synthesized with three different aspect ratios were estimated using the absorption spectra, size distributions, and the atomic spectroscopic analysis data. The previously accepted relationships between the extinction coefficient or the longitudinal band wavelength values and the nanorods{\textquoteright} aspect ratios found for the large nanorods do not extend to the small size domain reported in the present work. The failure of extending these relationships over larger sizes is a result of the interaction of light with the large rods giving an extinction band which results mostly from scattering processes while the extinction of the small nanorods results from absorption processes.},
	isbn = {0743-7463},
	doi = {10.1021/la301387p},
	author = {Ali, M. R. K. and Snyder, B. and El-Sayed, M. A.}
}
@article {1080,
	title = {Self-Standing Crystalline TiO(2) Nanotubes/CNTs Heterojunction Membrane: Synthesis and Characterization},
	journal = {Acs Applied Materials \& Interfaces},
	volume = {3},
	number = {4},
	year = {2011},
	note = {Hesabi, Zohreh R. Allam, Nageh K. Dahmen, Klaus Garmestani, Hamid El-Sayed, Mostafa A.},
	month = {Apr},
	pages = {952-955},
	abstract = {In the present study, we report for the first time synthesis of TiO(2) nanotubes/CNTs heterojunction membrane. Chemical vapor deposition (CVD) of CNTs at 650 degrees C in a mixture of H(2)/He atmosphere led to in situ detachment of the anodically fabricated TiO(2) nanotube layers from the Ti substrate underneath. Morphological and structural evolution of TiO(2) nanotubes after CNTs deposition were investigated by field- emission scanning electron microscopy (FESEM), glancing angle X-ray diffraction (GAXRD), and X-ray photoelectron spectroscopy (XPS) analyses.},
	isbn = {1944-8244},
	doi = {10.1021/am200124p},
	author = {Hesabi, Z. R. and Allam, N. K. and Dahmen, K. and Garmestani, H. and El-Sayed, Mostafa A}
}
@article {1090,
	title = {Surface Plasmon Fields and Coupling in the Hollow Gold Nanoparticles and Surface-Enhanced Raman Spectroscopy. Theory and Experiment},
	journal = {Journal of Physical Chemistry C},
	volume = {114},
	number = {16},
	year = {2010},
	note = {Mahmoud, M. A. Snyder, B. El-Sayed, M. A.},
	month = {Apr},
	pages = {7436-7443},
	abstract = {Most gold nanoparticles have surface plasmon fields only surrounding their surfaces. Recently, hollow nanoparticles have been studied, such as gold nanocages (AuNC) and gold nanoframes (ALINE). Those particles have two types of surfaces, one facing the outside and the other within the cavity. Their coupling provides a surface field inside the hollow particle and on the outside surface. Using DDA computational method, we have shown that the coupling between these fields gives field intensities and distribution inside and outside the nanoparticles that are sensitive to the thickness (the distance between the two surfaces) as well as the nanoparticle size. For small sizes, the coupling between the fields on the opposite sides of the cage is detected. These effects are detected by following the changes in the experimentally observed surface plasmon resonance spectra of these nanoparticles and the surface-enhanced Raman spectra of adsorbed molecules. The effect of the interaction between the external and internal field as well as the available surface area inside and outside the nanoparticle effects on the Raman-enhancement is detected by comparing the Raman intensities dependence on the interparticle distance with those observed on solid nanocubes surfaces.},
	isbn = {1932-7447},
	doi = {10.1021/jp9109018},
	author = {Mahmoud, M A and Snyder, B. and El-Sayed, Mostafa A}
}
@article {1110,
	title = {The sensitivity of the energy band gap to changes in the dimensions of the CdSe quantum rods at room temperature: STM and theoretical studies},
	journal = {Chemical Physics Letters},
	volume = {473},
	number = {4-6},
	year = {2009},
	note = {Talaat, H. Abdallah, T. Mohamed, M. B. Negm, S. El-Sayed, Mostafa A.},
	month = {May},
	pages = {288-292},
	abstract = {The energy band gap of a series of different sizes of CdSe quantum rods have been determined by STM technique at room temperature. The results confirm that the band gap of CdSe quantum rods (QRs) depends mainly on the width (the dimension of the electron confinement) and only slightly on the length as shown previously in the literatures. The experimental data is compared to that calculated using two theoretical models, the effective mass approximation (EMA) and the semi-empirical pseudopotential method (SEPM). The theoretical values for the energy band gap at varying radius are in agreement with the experimental results within 0.08 eV. (c) 2008 Published by Elsevier B.V.},
	isbn = {0009-2614},
	doi = {10.1016/j.cplett.2008.11.025},
	author = {Talaat, M. H. and Abdallah, T. and Mohamed, MB and Negm, S. and El-Sayed, Mostafa A}
}
@article {1115,
	title = {Surface-Enhanced Raman Scattering Enhancement by Aggregated Silver Nanocube Monolayers Assembled by the Langmuir-Blodgett Technique at Different Surface Pressures},
	journal = {Journal of Physical Chemistry C},
	volume = {113},
	number = {14},
	year = {2009},
	note = {Mahmoud, M. A. Tabor, C. E. El-Sayed, M. A.},
	month = {Apr},
	pages = {5493-5501},
	abstract = {The surface-enhanced Raman scattering spectrum of poly(vinyl) pyrrolidone (PVP) molecules capping 50 nm silver nanocubes assembled in a monolayer via the Langmuir-Blodgett (LB) technique is studied at different surface pressures (at different nanoparticle densities). The observed correlation between the intensity of different SERS bands of the PVP with the nanoparticle density and those of the extinction intensity of the localized surface plasmon resonance bands (as a measure of the surface plasmon field) suggests the following: (1) the observed SERS enhancement results mostly from surface fields of the aggregated nanoparticles; and (2) the relative intensities of the different Raman bands are in reasonable agreement with those expected from the electromagnetic mechanism of enhancement. Besides the large surface plasmon field used in the Raman scattering enhancement, the broad SPR band of the aggregated nanocubes provides an additional advantage in the analytical applications of Raman spectroscopy.},
	isbn = {1932-7447},
	doi = {10.1021/jp900648r},
	author = {Mahmoud, M A and Tabor, C. E. and El-Sayed, Mostafa A}
}
@article {1121,
	title = {Some aspects of colloidal nanoparticle stability, catalytic activity, and recycling potential},
	journal = {Topics in Catalysis},
	volume = {47},
	number = {1-2},
	year = {2008},
	note = {Narayanan, Radha El-Sayed, Mostafa A.},
	month = {Mar},
	pages = {15-21},
	abstract = {In this review article, we examine many important aspects of the nanocatalysis field such as size and shape dependent nanocatalysis, the stability of nanoparticles during its catalytic function, and their recycling potential. We provide an overview of some of the work in the literature pertinent to these topics and also discuss some of our own work in these important areas. Some examples of how the catalytic activity is affected by the size of the nanoparticles are discussed as well as how the catalytic process affects the nanoparticle size after its catalytic function. The synthesis of platinum nanoparticles of different shapes is surveyed and the dependence of nanoparticle shape on the catalytic activity is discussed. In addition, changes in the nanoparticle shape and resulting changes in the catalytic activity are also discussed. The recycling potential of the metal nanocatalysts is also highlighted. In addition, a simple examination of the mechanism of nanocatalysis is discussed.},
	isbn = {1022-5528},
	doi = {10.1007/s11244-007-9029-0},
	author = {Narayanan, Radha and El-Sayed, Mostafa A}
}
@article {1126,
	title = {Surface plasmon coupling and its universal size scaling in metal nanostructures of complex geometry: Elongated particle pairs and nanosphere trimers},
	journal = {Journal of Physical Chemistry C},
	volume = {112},
	number = {13},
	year = {2008},
	note = {Jain, Prashant K. El-Sayed, Mostafa A.},
	month = {Apr},
	pages = {4954-4960},
	abstract = {Recently, we showed that the plasmon resonance coupling between two interacting metal nanoparticles decays with the interparticle separation (in units of particle size) with the same universal trend independent of particle size or shape, metal type, or medium. This universal scaling behavior has been shown to apply to lithographically fabricated nanoparticle pairs, the metal nanoshell, plasmonic dielectric sensors, and the plasmon ruler useful in determining intersite distances in biological systems. In this article, we use electrodynamic simulations to examine the general applicability of this universal scaling behavior to more complex nanostructure geometries, for example, head-to-tail dimers of elongated particles of different aspect ratios and curvatures and a trimer of nanospheres. We find that the plasmon coupling between two elongated nanoparticles interacting head-to-tail decays according to the same universal law if the interparticle separation is scaled by the particle long-axis dimension. The absolute plasmon coupling strength, however, depends on the particle shape (i.e., aspect ratio and curvature), without affecting the universal scaling behavior. We also show that universal scaling is valid in a system of three interacting nanospheres, a first step toward extending this model to chains/arrays/assemblies of metal nanoparticles.},
	isbn = {1932-7447},
	doi = {10.1021/jp7120356},
	author = {Jain, Prashant K and El-Sayed, Mostafa A}
}
@article {813,
	title = {Surface Plasmon Resonance Sensitivity of Metal Nanostructures:  Physical Basis and Universal Scaling in Metal Nanoshells},
	journal = {The Journal of Physical Chemistry C},
	volume = {111},
	year = {2007},
	note = {doi: 10.1021/jp0773177},
	month = {2007},
	pages = {17451 - 17454},
	publisher = {American Chemical Society},
	abstract = {In this letter, we show using extended Mie theory simulations that the sensitivity of the surface plasmon resonance (SPR) of a dielectric core-metal nanoshell increases near-exponentially as the ratio of the shell thickness-to-core radius is decreased. The plasmon sensitivity thus shows the same universal scaling behavior established recently for plasmon coupling in metal nanoshells and that in metal nanoparticle pairs. From these observations, we propose that the sensitivity is determined by the ease of surface polarization of the electrons in the nanostructure by the light. This can be used as a generalized physical principle for designing plasmonic nanostructures for effective SPR chemical and biological sensing.In this letter, we show using extended Mie theory simulations that the sensitivity of the surface plasmon resonance (SPR) of a dielectric core-metal nanoshell increases near-exponentially as the ratio of the shell thickness-to-core radius is decreased. The plasmon sensitivity thus shows the same universal scaling behavior established recently for plasmon coupling in metal nanoshells and that in metal nanoparticle pairs. From these observations, we propose that the sensitivity is determined by the ease of surface polarization of the electrons in the nanostructure by the light. This can be used as a generalized physical principle for designing plasmonic nanostructures for effective SPR chemical and biological sensing.},
	isbn = {1932-7447},
	doi = {10.1021/jp0773177},
	url = {http://dx.doi.org/10.1021/jp0773177},
	author = {Jain, Prashant K and El-Sayed, Mostafa A}
}
@article {1158,
	title = {Selective laser photo-thermal therapy of epithelial carcinoma using anti-EGFR antibody conjugated gold nanoparticles},
	journal = {Cancer Letters},
	volume = {239},
	number = {1},
	year = {2006},
	note = {El-Sayed, Ivan H. Huang, Xiaohua El-Sayed, Mostafa A.},
	month = {Jul},
	pages = {129-135},
	abstract = {Efficient conversion of strongly absorbed light by plasmonic gold nanoparticles to heat energy and their easy bioconjugation suggest their use as selective photothermal agents in molecular cancer cell targeting. Two oral squamous carcinoma cell lines (HSC 313 and HOC 3 Clone 8) and one benign epithelial cell line (HaCaT) were incubated with anti-epithelial growth factor receptor (EGFR) antibody conjugated gold nanoparticles and then exposed to continuous visible argon ion laser at 514 nm. It is found that the malignant cells require less than half the laser energy to be killed than the benign cells after incubation with anti-EGFR antibody conjugated Au nanoparticles. No photothermal destruction is observed for all types of cells in the absence of nanoparticles at four times energy required to kill the malignant cells with anti-EGFR/Au conjugates bonded. An nanoparticles thus offer a novel class of selective photothermal agents using a CW laser at low powers. The potential of using this selective technique in molecularly targeted photothermal therapy in vivo is discussed (c) 2005 Elsevier Ireland Ltd. All rights reserved.},
	isbn = {0304-3835},
	doi = {10.1016/j.canlet.2005.07.035},
	author = {El Sayed, I.H. and Huang, Xiaohua and El-Sayed, Mostafa A}
}
@article {1159,
	title = {Size-dependent ultrafast electronic energy relaxation and enhanced fluorescence of copper nanoparticles},
	journal = {Journal of Physical Chemistry B},
	volume = {110},
	number = {1},
	year = {2006},
	note = {Darugar, Q Qian, W El-Sayed, MA Pileni, MP},
	month = {Jan},
	pages = {143-149},
	abstract = {The energy relaxation of the electrons in the conduction band of 12 and 30 nm diameter copper nanoparticles in colloidal solution was investigated using femtosecond time-resolved transient spectroscopy. Experimental results show that the hot electron energy relaxation is faster in 12 nm copper nanoparticles (0.37 ps) than that in 30 nm copper nanoparticles (0.51 ps), which is explained by the size-dependent electron-surface phonon coupling. Additional mechanisms involving trapping or energy transfer processes to the denser surface states (imperfection) in the smaller nanoparticles are needed to explain the relaxation rate in the 12 nm nanoparticles. The observed fluorescence quantum yield from these nanoparticles is found to be enhanced by roughly 5 orders of magnitude for the 30 nm nanoparticles and 4 orders of magnitude for the 12 nm nanoparticles (relative to bulk copper metal). The increase in the fluorescence quantum yield is attributed to the electromagnetic enhancement of the radiative recombination of the electrons in the s-p conduction band below the Fermi level with the holes in the d bands due to the strong surface plasmon oscillation in these nanoparticles.},
	isbn = {1520-6106},
	doi = {10.1021/jp0545445},
	author = {Darugar, Q. and Qian, Wei and El-Sayed, Mostafa A and Pileni, Marie-Paule}
}
@article {823,
	title = {Simulation of the Optical Absorption Spectra of Gold Nanorods as a Function of Their Aspect Ratio and the Effect of the Medium Dielectric Constant},
	journal = {The Journal of Physical Chemistry B},
	volume = {109},
	year = {2005},
	note = {doi: 10.1021/jp058091f},
	month = {2005},
	pages = {10531 - 10532},
	publisher = {American Chemical Society},
	isbn = {1520-6106},
	doi = {10.1021/jp058091f},
	url = {http://dx.doi.org/10.1021/jp058091f},
	author = {Link, Stephan and El-Sayed, Mostafa A}
}
@article {1173,
	title = {Surface plasmon resonance scattering and absorption of anti-EGFR antibody conjugated gold nanoparticles in cancer diagnostics: Applications in oral cancer},
	journal = {Nano Letters},
	volume = {5},
	number = {5},
	year = {2005},
	note = {El-Sayed, IH Huang, XH El-Sayed, MA},
	month = {May},
	pages = {829-834},
	abstract = {Gold nanoparticles with unique optical properties may be useful as biosensors in living whole cells. Using a simple and inexpensive technique, we recorded surface plasmon resonance (SPR) scattering images and SPR absorption spectra from both colloidal gold nanoparticles and from gold nanoparticles conjugated to monoclonal anti-epidermal growth factor receptor (anti-EGFR) antibodies after incubation in cell cultures with a nonmalignant epithelial cell line (HaCaT) and two malignant oral epithelial cell lines (HOC 313 clone 8 and HSC 3). Colloidal gold nanoparticles are found in dispersed and aggregated forms within the cell cytoplasm and provide anatomic labeling information, but their uptake is nonspecific for malignant cells. The anti-EGFR antibody conjugated nanoparticles specifically and homogeneously bind to the surface of the cancer type cells with 600\% greater affinity than to the noncancerous cells. This specific and homogeneous binding is found to give a relatively sharper SPR absorption band with a red shifted maximum compared to that observed when added to the noncancerous cells. These results suggest that SPR scattering imaging or SPR absorption spectroscopy generated from antibody conjugated gold nanoparticles can be useful in molecular biosensor techniques for the diagnosis and investigation of oral epithelial living cancer cells in vivo and in vitro.},
	keywords = {display},
	isbn = {1530-6984},
	doi = {10.1021/nl050074e},
	author = {El Sayed, I.H. and Huang, Xiaohua and El-Sayed, Mostafa A.}
}
@article {839,
	title = {Shape control of platinum nanoparticles by using different capping organic materials},
	journal = {BULLETIN-KOREAN CHEMICAL SOCIETY},
	volume = {25},
	year = {2004},
	pages = {395},
	abstract = {No Abstract},
	keywords = {Cube, Nanoparticle, Platinum, Transmission electron microscopy, Truncated octahedra},
	url = {http://newjournal.kcsnet.or.kr/main/j_search/j_abstract_view.htm?code=B040315\&qpage=j_search\&spage=b_bkcs\&dpage=ar},
	author = {Yoo, J. W. and Lee, S.M. and Kim, H.T. and El-Sayed, Mostafa A}
}
@article {1175,
	title = {Shape-dependent catalytic activity of platinum nanoparticles in colloidal solution},
	journal = {Nano Letters},
	volume = {4},
	number = {7},
	year = {2004},
	note = {Narayanan, R El-Sayed, MA},
	month = {Jul},
	pages = {1343-1348},
	abstract = {The activation energies and the average rate constants are determined in the 298 K-318 K temperature range for the early stages of the nanocatalytic reaction between hexacyanoferrate (111) and thiosulfate ions using 4.8 +/- 0.1 nm tetrahedral, 7.1 +/- 0.2 nm cubic, and 4.9 +/- 0.1 nm "near spherical" nanocrystals. These kinetic parameters are found to correlate with the calculated fraction of surface atoms located on the corners and edges in each size and shape.},
	isbn = {1530-6984},
	doi = {10.1021/nl0495256},
	author = {Narayanan, Radha and El-Sayed, Mostafa A}
}
@article {1182,
	title = {Small is different: Shape-, size-, and composition-dependent properties of some colloidal semiconductor nanocrystals},
	journal = {Accounts of Chemical Research},
	volume = {37},
	number = {5},
	year = {2004},
	note = {El-Sayed, MA},
	month = {May},
	pages = {326-333},
	abstract = {As the size of material becomes equal to or falls below the nanometer length scale that characterizes the motion of its electrons and thus its properties, the latter become sensitive not only to the size but also to the shape and composition of the particles. In this Account, we describe the changes of some interesting properties in different colloidal semiconductor nanoparticles, such as the electronic relaxation rates as spherical nanoparticles change to nanorods, and the changes in the structure or size of very small nanoparticles upon adsorbing strongly bound molecules. We have also determined and explained the difference in the interfacial crossing rates of electrons and holes in a composite nanostructure.},
	isbn = {0001-4842},
	doi = {10.1021/ar020204f},
	author = {El-Sayed, Mostafa A}
}
@article {844,
	title = {Surface-Enhanced Raman Scattering Studies on Aggregated Gold Nanorods},
	journal = {The Journal of Physical Chemistry AThe Journal of Physical Chemistry A},
	volume = {107},
	year = {2003},
	note = {doi: 10.1021/jp026770+},
	month = {2003},
	pages = {3372 - 3378},
	publisher = {American Chemical Society},
	abstract = {Surface-enhanced Raman scattering (SERS) of adsorbed molecules on gold nanorods (NRs) with dimensions of 10 nm ? 27 nm was studied on silica surface with low to high surface coverage of NRs. The study was carried out to investigate both the dependence of the SERS intensity on the number of NRs and the NRs spacing on the silica surface. SERS of adsorbed molecules such as 2-aminothiophenol (2-ATP) and the capping molecules (hexadecyltrimethylammonium bromide) was studied on these surfaces using a near-IR laser excitation source (1064 nm). To produce silica surfaces covered with NRs, two approaches were used. In the first approach, monodispersed NRs gradually deposited from solution to silica surface and their number was increased by increasing the deposition time. In the second one, the NRs were first aggregated in solution and then deposited on the surface. Although using the first approach it was possible to prepare surfaces with high NR surface coverage, SERS intensity was found to be stronger for adsorbed molecules on surfaces covered with aggregated NRs. The observed increase in the SERS intensity in the case of aggregation was attributed to the enhancement of the electric field between the particles in the aggregates. It is shown that aggregated NRs in comparison with aggregated nanospheres (NSs) have stronger SERS enhancement under similar experimental conditions. In this comparison, some of the enhanced vibrational bands of 2-ATP on aggregated NRs are weakly enhanced or absent on aggregated NSs. Monitoring the SERS intensity of adsorbed 2-ATP versus its exposure time to the aggregated NRs shows that the SERS intensity of the adsorbed molecules reaches saturation, whereas the peak intensities of the capping molecules remain unchanged. The intensity saturation was discussed in terms of factors such as the saturation of the SERS active sites for 2-ATP on the gold surface and the partial damping of the plasmon band due to the stronger interaction of the adsorbate molecules with the metal surface.Surface-enhanced Raman scattering (SERS) of adsorbed molecules on gold nanorods (NRs) with dimensions of 10 nm ? 27 nm was studied on silica surface with low to high surface coverage of NRs. The study was carried out to investigate both the dependence of the SERS intensity on the number of NRs and the NRs spacing on the silica surface. SERS of adsorbed molecules such as 2-aminothiophenol (2-ATP) and the capping molecules (hexadecyltrimethylammonium bromide) was studied on these surfaces using a near-IR laser excitation source (1064 nm). To produce silica surfaces covered with NRs, two approaches were used. In the first approach, monodispersed NRs gradually deposited from solution to silica surface and their number was increased by increasing the deposition time. In the second one, the NRs were first aggregated in solution and then deposited on the surface. Although using the first approach it was possible to prepare surfaces with high NR surface coverage, SERS intensity was found to be stronger for adsorbed molecules on surfaces covered with aggregated NRs. The observed increase in the SERS intensity in the case of aggregation was attributed to the enhancement of the electric field between the particles in the aggregates. It is shown that aggregated NRs in comparison with aggregated nanospheres (NSs) have stronger SERS enhancement under similar experimental conditions. In this comparison, some of the enhanced vibrational bands of 2-ATP on aggregated NRs are weakly enhanced or absent on aggregated NSs. Monitoring the SERS intensity of adsorbed 2-ATP versus its exposure time to the aggregated NRs shows that the SERS intensity of the adsorbed molecules reaches saturation, whereas the peak intensities of the capping molecules remain unchanged. The intensity saturation was discussed in terms of factors such as the saturation of the SERS active sites for 2-ATP on the gold surface and the partial damping of the plasmon band due to the stronger interaction of the adsorbate molecules with the metal surface.},
	isbn = {1089-5639},
	doi = {10.1021/jp026770+},
	url = {http://dx.doi.org/10.1021/jp026770+},
	author = {Nikoobakht, Babak and El-Sayed, Mostafa A}
}
@article {1200,
	title = {Size effects of PVP-Pd nanoparticles on the catalytic Suzuki reactions in aqueous solution},
	journal = {Langmuir},
	volume = {18},
	number = {12},
	year = {2002},
	note = {Li, Y Boone, E El-Sayed, MA},
	month = {Jun},
	pages = {4921-4925},
	abstract = {A series of poly(N-vinyl-2-pyrrolidone) (PVP)-stabilized Pd nanoparticles with varying particle size are prepared by using the stepwise growth reaction. The effect of Pd particle size on the Suzuki reaction between phenylboronic acid and iodobenzene is investigated by the use of four Pd catalysts with mean particle sizes of 3.0, 3.9, 5.2, and 6.6 nm, respectively. The catalytic activity of the Pd nanoparticles expressed in terms of the initial turnover frequency (moles of the biphenyl product per mole of total surface Pd atoms per min) is found to be in the order of Pd (3.9 nm) > Pd (3.0 nm) approximate to Pd (5.2 nm) > Pd (6.6 nm), indicating that surface Pd atoms do not all have the same reactivity in this reaction. The general trend of increased catalytic activity with the decrease in the particle size suggests that the low-coordination number vertex and edge atoms on the particle surface are active sites for the Suzuki reaction. The lower catalytic activity for the smallest Pd nanoparticles might be due to stronger adsorption of the reaction intermediates on the particle surface, in which the strongly adsorbed species act as a poison to the reaction thereby decreasing the rate of the reaction.},
	isbn = {0743-7463},
	doi = {10.1021/la011469q},
	author = {Li, Y. and Boone, E. and El-Sayed, Mostafa A}
}
@article {1194,
	title = {Surface-enhanced Raman scattering of molecules adsorbed on gold nanorods: off-surface plasmon resonance condition},
	journal = {Chemical Physics Letters},
	volume = {366},
	number = {1-2},
	year = {2002},
	note = {Nikoobakht, B Wang, JP El-Sayed, MA},
	month = {Nov},
	pages = {17-23},
	abstract = {The Raman spectra of several molecules adsorbed on gold nanospheres (NSs) (12 nm in diameter) and nanorods (NRs) (25 nm x 10 nm) are studied using an off-plasmon resonance excitation condition. The studies are carried out in colloidal solution and on solid substrates. Enhancement factors on the order of 10(4)-10(5) are observed for the adsorbed molecules on the NRs, however, no such enhancement was observed on NSs under similar condition. These factors are two orders of magnitude larger than the calculated value using the Wang and Kerker electromagnetic model. This suggests a contribution from the chemical mechanism in the observed enhancement. (C) 2002 Published by Elsevier Science B.V.},
	isbn = {0009-2614},
	doi = {10.1016/s0009-2614(02)01492-6},
	author = {Nikoobakht, Babak and Wang, Jianping and El-Sayed, Mostafa A}
}
@article {1208,
	title = {Self-assembly of platinum nanoparticles of various size and shape},
	journal = {Journal of Physical Chemistry A},
	volume = {105},
	number = {23},
	year = {2001},
	note = {Petroski, JM Green, TC El-Sayed, MA},
	month = {Jun},
	pages = {5542-5547},
	abstract = {The addition of dodecanethiol to a polydisperse platinum colloidal aqueous solution capped with acrylic acid leads to self-assembled monolayers which not only contain various sizes, but also various shapes of nanoparticles. Assembled monolayers arranged in hcp arrays are achieved for mixed shape-samples. In;the case of the assembly of cubic nanoparticles, cubic closest packing is achieved when the size difference between the nanoparticles is less than 25\% (or between 6 and 8 nm). The ccp array is disrupted when the size difference is between 25 and 60\% or there is a mixture of shapes. Finally, size segregation is seen in regions where the size difference is more than 60\% with the resultant assembly being hcp no matter what the shape.},
	isbn = {1089-5639},
	doi = {10.1021/jp0019207},
	author = {Petroski, J. M. and Green, T.C. and El-Sayed, Mostafa A}
}
@article {1218,
	title = {Some interesting properties of metals confined in time and nanometer space of different shapes},
	journal = {Accounts of Chemical Research},
	volume = {34},
	number = {4},
	year = {2001},
	note = {El-Sayed, MA},
	month = {Apr},
	pages = {257-264},
	abstract = {The properties of a material depend on the type of motion its electrons can execute, which depends on the space available for them (i.e., on the degree of their spatial confinement). Thus, the properties of each material are characterized by a specific length scale, usually on the nanometer dimension. If the physical size of the material is reduced below this length scale, its properties change and become sensitive to its size and shape. In this Account we describe some of the observed new chemical, optical, and thermal properties of metallic nanocrystals when their size is confined to the nanometer length scale and their dynamical processes are observed on the femto- to picosecond time scale.},
	isbn = {0001-4842},
	doi = {10.1021/ar960016n},
	author = {El-Sayed, Mostafa A}
}
@article {1213,
	title = {Spectroscopic determination of the melting energy of a gold nanorod},
	journal = {Journal of Chemical Physics},
	volume = {114},
	number = {5},
	year = {2001},
	note = {Link, S El-Sayed, MA},
	month = {Feb},
	pages = {2362-2368},
	abstract = {Gold nanorods in colloidal solution can be melted into spherical nanoparticles by excitation with intense femtosecond laser pulses of the proper energy. The threshold of the laser pulse energy for the complete melting of the nanorods with a mean aspect ratio of 4.1 in solution is determined by observing the change in the absorption intensity of the longitudinal absorption band (measure of the rod concentration) at 800 nm with increasing number of laser pulses of known energy. The number of laser pulses needed to reduce the band intensity (rod concentration) by 1/e of its initial value is determined as the laser energy per pulse increases. For pulses of lower energy than threshold, it is found that the number of pulses required to melt the gold nanorods present in solution increases significantly with decreasing laser pulse energy. Above threshold, this number is constant since the additional absorbed laser energy will only further heat the particles to temperatures above their melting point. The gold concentration in the colloidal solution is measured using inductively coupled plasma atomic emission spectroscopy (ICP-AES), from which the gold nanorod concentration is determined from the known shape and size distribution obtained from transmission electron microscopy (TEM) results. A simple analysis using the determined threshold energy and the nanorod concentration showed that it takes an average of similar to 60 femtojoule (fJ) to melt a single gold nanorod. Experiments using 820 nm as well as 410 nm femtosecond laser pulses yield similar values, indicating that the laser induced shape transformation of the nanorods is independent of the irradiation wavelength and that this process is therefore photothermal in origin. (C) 2001 American Institute of Physics.},
	isbn = {0021-9606},
	doi = {10.1063/1.1336140},
	author = {Link, Stephan and El-Sayed, Mostafa A}
}
@article {1223,
	title = {Self-assembly of gold nanorods},
	journal = {Journal of Physical Chemistry B},
	volume = {104},
	number = {36},
	year = {2000},
	note = {Nikoobakht, B Wang, ZL El-Sayed, MA},
	month = {Sep},
	pages = {8635-8640},
	abstract = {Self-assembly of gold nanorods (NRs) with aspect ratio of similar to 4.6 (12 nm in diameter and 50-60 nm in length) has been studied using transmission electron microscopy (TEM). Under appropriate conditions such as nanoparticle concentration, solvent evaporation, narrow size distribution, ionic strength, and surfactant concentration of the parent solution, gold nanorods assemble into one-, two-, and three-dimensional structures. Some of the three-dimensional assemblies extend to superlattices of NRs. The translation and orientation symmetries of the self-assembled structures are determined. The factors affecting the formation of the ordered self-assembly are discussed.},
	isbn = {1089-5647},
	doi = {10.1021/jp001287p},
	author = {Nikoobakht, Babak and Wang, Z.L. and El-Sayed, Mostafa A}
}
@article {1227,
	title = {Shape and size dependence of radiative, non-radiative and photothermal properties of gold nanocrystals},
	journal = {International Reviews in Physical Chemistry},
	volume = {19},
	number = {3},
	year = {2000},
	note = {Link, S El-Sayed, MA},
	month = {Jul-Sep},
	pages = {409-453},
	abstract = {Driven by the search for new materials with interesting and unique properties and also by the fundamental question of how atomic and molecular physical behaviour develops with increasing size, the field of nanoparticle research has grown immensely in the last two decades. Partially for these reasons, colloidal solutions of metallic (especially silver and gold) nanoparticles have long fascinated scientists because of their very intense colours. The intense red colour of colloidal gold nanoparticles is due to their surface plasmon absorption. This article describes the physical origin of the surface plasmon absorption in gold nanoparticles with emphasis on the Mie and also the MaxweIl-Garnett theory and reviews the effects of particle size and shape on the resonance condition. A better understanding of the relationship between the optical absorption spectrum (in particular, the plasmon resonance) and such particle properties as its dimensions or surrounding environment can prove fruitful for the use of the plasmon absorption as an analytical tool. The plasmon resonance has also had a great impact on the Raman spectrum of surface-adsorbed molecules and a large enhancement of the fluorescence quantum yield of gold nanorods is observed. Furthermore, following the changes in the plasmon absorption induced by excitation (heating) with ultrashort laser pulses allows one to monitor the electron dynamics (electron-electron and electron-phonon interactions) in real time, which is important in understanding such fundamental questions regarding the thermal and electrical conductivity of these nanoparticles. Very intense heating with laser pulses leads to structural changes of the nanoparticles (nuclear rearrangements in the form of melting and fragmentation).},
	isbn = {0144-235X},
	doi = {10.1080/01442350050034180},
	author = {Link, Stephan and El-Sayed, Mostafa A}
}
@article {1220,
	title = {Surface reconstruction of the unstable {110} surface in gold nanorods},
	journal = {Journal of Physical Chemistry B},
	volume = {104},
	number = {23},
	year = {2000},
	note = {Wang, ZL Gao, RP Nikoobakht, B El-Sayed, MA},
	month = {Jun},
	pages = {5417-5420},
	abstract = {Gold nanorods prepared electrochemically and capped in micelles are examined using high-resolution transmission electron microscopy (TEM), It is found that they have an axial growth direction of [001] and have surfaces made of {100} and the unstable {110} facets. A detailed examination of the defect sites of both of these facets shows that while the defective regions of the stable {100} facets show atom-height steps with no reconstruction, the less stable higher energy {110} surfaces show missing-row reconstruction. The role of micelles in stabilizing the {110} facet in the gold nanorod is briefly discussed.},
	isbn = {1089-5647},
	doi = {10.1021/jp000800w},
	author = {Wang, Z.L. and Gao, R. P. and Nikoobakht, Babak and El-Sayed, Mostafa A}
}
@article {1231,
	title = {Suzuki cross-coupling reactions catalyzed by palladium nanoparticles in aqueous solution},
	journal = {Organic Letters},
	volume = {2},
	number = {15},
	year = {2000},
	note = {Li, Y Hong, XM Collard, DM El-Sayed, MA},
	month = {Jul},
	pages = {2385-2388},
	abstract = {[GRAPHICS] Palladium nanoparticles stabilized by poly(N-vinyl-2-pyrrolidone) (PVP) are efficient catalysts for the Suzuki reactions in aqueous medium. The time dependence of the fluorescence intensity of the biphenyl product in the reaction between iodobenzene and phenylboronic acid is used to determine the initial rate of the catalytic reaction. The initial rate depends linearly on the concentration of Pd catalyst, suggesting that the catalytic reaction occurs on the surface of the Pd nanoparticles.},
	isbn = {1523-7060},
	doi = {10.1021/ol0061687},
	author = {Li, Y. and Hong, X. M. and Collard, D. M. and El-Sayed, Mostafa A}
}
@article {1241,
	title = {Simulation of the optical absorption spectra of gold nanorods as a function of their aspect ratio and the effect of the medium dielectric constant},
	journal = {Journal of Physical Chemistry B},
	volume = {103},
	number = {16},
	year = {1999},
	note = {Link, S Mohamed, MB El-Sayed, MA},
	month = {Apr},
	pages = {3073-3077},
	abstract = {Gold nanorods with different aspect ratios are prepared in micelles by the electrochemical method and their absorption spectra are modeled by theory. Experimentally, a linear relationship is found between the absorption maximum of the longitudinal plasmon resonance and the mean aspect ratio as determined from TEM. It is shown here that such a linear dependence is also predicted theoretically. However, calculations also show that the absorption maximum of the longitudinal plasmon resonance depends on the medium dielectric constant in a linear fashion for a fixed aspect ratio. Attempts to fit the calculations to the experimental values indicate that the medium dielectric constant has to vary with the aspect ratio in a nonlinear way. Chemically, this suggests that the structure of the micelle capping the gold nanorods is size dependent. Furthermore, comparison with the results obtained for rods of different aspect ratios made by systematic thermal decomposition of the long rods further suggests that the medium dielectric constant is also temperature dependent. This is attributed to thermal annealing of the structure of the micelles around the nanorods.},
	isbn = {1089-5647},
	doi = {10.1021/jp990183f},
	author = {Link, Stephan and Mohamed, MB and El-Sayed, Mostafa A}
}
@article {834,
	title = {Simulation of the Optical Absorption Spectra of Gold Nanorods as a Function of Their Aspect Ratio and the Effect of the Medium Dielectric Constant},
	journal = {The Journal of Physical Chemistry B },
	volume = {103},
	year = {1999},
	note = {doi: 10.1021/jp990183f},
	month = {1999},
	pages = {3073 - 3077},
	publisher = {American Chemical Society},
	abstract = {Gold nanorods with different aspect ratios are prepared in micelles by the electrochemical method and their absorption spectra are modeled by theory. Experimentally, a linear relationship is found between the absorption maximum of the longitudinal plasmon resonance and the mean aspect ratio as determined from TEM. It is shown here that such a linear dependence is also predicted theoretically. However, calculations also show that the absorption maximum of the longitudinal plasmon resonance depends on the medium dielectric constant in a linear fashion for a fixed aspect ratio. Attempts to fit the calculations to the experimental values indicate that the medium dielectric constant has to vary with the aspect ratio in a nonlinear way. Chemically, this suggests that the structure of the micelle capping the gold nanorods is size dependent. Furthermore, comparison with the results obtained for rods of different aspect ratios made by systematic thermal decomposition of the long rods further suggests that the medium dielectric constant is also temperature dependent. This is attributed to thermal annealing of the structure of the micelles around the nanorods.Gold nanorods with different aspect ratios are prepared in micelles by the electrochemical method and their absorption spectra are modeled by theory. Experimentally, a linear relationship is found between the absorption maximum of the longitudinal plasmon resonance and the mean aspect ratio as determined from TEM. It is shown here that such a linear dependence is also predicted theoretically. However, calculations also show that the absorption maximum of the longitudinal plasmon resonance depends on the medium dielectric constant in a linear fashion for a fixed aspect ratio. Attempts to fit the calculations to the experimental values indicate that the medium dielectric constant has to vary with the aspect ratio in a nonlinear way. Chemically, this suggests that the structure of the micelle capping the gold nanorods is size dependent. Furthermore, comparison with the results obtained for rods of different aspect ratios made by systematic thermal decomposition of the long rods further suggests that the medium dielectric constant is also temperature dependent. This is attributed to thermal annealing of the structure of the micelles around the nanorods.},
	isbn = {1520-6106},
	url = {http://dx.doi.org/10.1021/jp990183f},
	author = {Link, Stephan and Mohamed, MB and El-Sayed, Mostafa A}
}
@article {1243,
	title = {Size and temperature dependence of the plasmon absorption of colloidal gold nanoparticles},
	journal = {Journal of Physical Chemistry B},
	volume = {103},
	number = {21},
	year = {1999},
	note = {Link, S El-Sayed, MA},
	month = {May},
	pages = {4212-4217},
	abstract = {The size and temperature dependence of the plasmon absorption is studied for 9, 15, 22, 48, and 99 nm gold nanoparticles in aqueous solution. The plasmon bandwidth is found to follow the predicted behavior as it increases with decreasing size in the intrinsic size region (mean diameter smaller than 25 nm), and also increases with increasing size in the extrinsic size region (mean diameter larger than 25 nm). Because of this pronounced size effect a homogeneous size distribution and therefore a homogeneous broadening of the plasmon band is concluded for all the prepared gold nanoparticle samples. By applying a simple two-level model the dephasing time of the coherent plasmon oscillation is calculated and found to be less than 5 fs. Furthermore, the temperature dependence of the plasmon absorption is examined. A small temperature effect is observed. This is consistent with the fact that the dominant electronic dephasing mechanism involves electron-electron interactions rather than electron-phonon coupling.},
	isbn = {1089-5647},
	doi = {10.1021/jp984796o},
	author = {Link, Stephan and El-Sayed, Mostafa A}
}
@article {1242,
	title = {Spectral properties and relaxation dynamics of surface plasmon electronic oscillations in gold and silver nanodots and nanorods},
	journal = {Journal of Physical Chemistry B},
	volume = {103},
	number = {40},
	year = {1999},
	note = {Link, S El-Sayed, MA},
	month = {Oct},
	pages = {8410-8426},
	abstract = {The field of nanoparticle research has drawn much attention in the past decade as a result of the search for new materials. Size confinement results in new electronic and optical properties, possibly suitable for many electronic and optoelectronic applications. A characteristic feature of noble metal nanoparticles is the strong color of their colloidal solutions, which is caused by the surface plasmon absorption. This article describes our studies of the properties of the surface plasmon absorption in metal nanoparticles that range in size between 10 and 100 nm. The effects of size, shape, and composition on the plasmon absorption maximum and its bandwidth are discussed. Furthermore, the optical response of the surface plasmon absorption due to excitation with femtosecond laser pulses allowed us to follow the electron dynamics (electron-electron and electron-phonon scattering) in these metal nanoparticles. It: is found that the electron-phonon relaxation processes in nanoparticles, which are smaller than the electron mean free path, are independent of their size or shape. Intense laser heating of the electrons in these particles is also found to cause a shape transformation (photoisomerization of the rods into spheres or fragmentation), which depends on the laser pulse energy and pulse width.},
	isbn = {1089-5647},
	doi = {10.1021/jp9917648},
	author = {Link, Stephan and El-Sayed, Mostafa A}
}
@article {1249,
	title = {Shape transformation and surface melting of cubic and tetrahedral platinum nanocrystals},
	journal = {Journal of Physical Chemistry B},
	volume = {102},
	number = {32},
	year = {1998},
	note = {Wang, ZL Petroski, JM Green, TC El-Sayed, MA},
	month = {Aug},
	pages = {6145-6151},
	abstract = {We report transmission electron microscopic studies of in-situ temperature-induced shape transformation and melting behavior of polymer-capped cubic and tetrahedral nanocrystals. Our results indicate that the surface-capping polymer is removed by annealing the specimen at temperatures between 180 and 250 degrees C. The particle shapes show no change up to similar to 350 degrees C. In the temperature range between 350 and 450 degrees C, a small truncation occurs in the particle shapes but no major shape transformation is observed. The particle shapes experience a dramatic transformation into spherical-like shapes when the temperature is raised above similar to 500 degrees C, where surface diffusion or surface premelting (softening) takes place. Above 600 degrees C, surface melting becomes obvious leading to coalescence of the surfaces of neighboring nanocrystals and a decrease in the volume occupied by the assembled nanocrystals. The surface melting forms a liquid layer a few atomic layers deep around the still solid core of the nanocrystal. This temperature is much lower than the melting point of bulk metallic platinum (1769 degrees C). The reduction in the melting temperature is discussed in terms of the surface tension of the solid-liquid interface (gamma(SL)). For an 8 nm diameter Pt nanocrystal, gamma(SL) is calculated to be 2.0 N m(-1) at 650 degrees C, which is smaller than that of the bulk solid-vapor metal surface tension (gamma(sv)). This reduction is proposed to be due to the compensation of the increase in gamma(sv) of the nanocrystal by the wetting effect at the solid-liquid interface.},
	isbn = {1089-5647},
	doi = {10.1021/jp981594j},
	author = {Wang, Z.L. and Petroski, J. M. and Green, T.C. and El-Sayed, Mostafa A}
}
@article {1261,
	title = {Spectral diffusion within the porous silicon emission wavelength range on the nanosecond to millisecond time scale},
	journal = {J. Appl. Phys.Journal of Applied Physics},
	volume = {82},
	year = {1997},
	month = {1997},
	pages = {836},
	publisher = {AIP},
	abstract = {The emission spectrum from porous silicon (PS) at room temperature was recorded after different delay times ranging from 30 ns to 2.0 ms after pulsed laser excitation by using a gated charge-coupled device camera. In agreement with previous studies, the photoluminescence of porous silicon was found to redshift with delay time in the ns to 100 μs time scale. However, a study of the normalized band shape of the redshifted emission reveals that the emission spectrum retains its band shape rather than giving a distorted band shape that increases in intensity on the longer wavelength side. This behavior suggests that the redshift in the emission spectrum of porous silicon is a result of spectral diffusion resulting from energy transfer among emitters within the inhomogeneously broadened absorption spectrum. Furthermore, on the longer time scale (0.8{\textendash}2 ms), the much weaker, long wavelength emission spectrum is found to blueshift as the delay time is increased. Two peaks were resolved in the photoluminescence spectrum. One is centered around 650 nm and the other is centered around 750 nm. The photoluminescence at 600 and 800 nm have lifetimes of 0.35 and 0.19 ms, respectively. This observation suggests the existence of two distinct molecular species responsible for the observed photoluminescence in PS.},
	keywords = {elemental semiconductors, photoluminescence, porous materials, radiative lifetimes, red shift, silicon, spectral line breadth, spectral line shift, time resolved spectra},
	url = {http://dx.doi.org/10.1063/1.365781},
	author = {Song, Li},
	editor = {El-Sayed, Mostafa A and Chen, P.}
}
@article {871,
	title = {Steps, ledges and kinks on the surfaces of platinum nanoparticles of different shapes},
	journal = {Surface science},
	volume = {380},
	year = {1997},
	pages = {302-310},
	publisher = {Elsevier},
	abstract = {Platinum nanoparticles with a high percentage of cubic-, tetrahedral- and octahedral-like shapes, respectively, have been synthesized by a shape-controlling technique that we developed recently [Ahmadi et al., Science 272 (June 1996) 1924]. High resolution transmission electron microscopy (HRTEM) is used here to directly image the atomic scale structures of the surfaces of these particles with different shapes. The truncated shapes of these particles are mainly defined by the {100}, {111}, and {110} facets, on which numerous atom-high surface steps, ledges and kinds have been observed. This atomic-scale fine structure of the surfaces of these particles is expected to play a critical role in their catalytic activity and selectivity.},
	isbn = {0039-6028},
	doi = {10.1016/S0039-6028(97)05180-7 },
	author = {Wang, Z.L. and Ahmad, TS and El-Sayed, Mostafa A}
}
@article {865,
	title = {Studies of cation binding in ZnCl2-regenerated bacteriorhodopsin by x-ray absorption fine structures: effects of removing water molecules and adding Cl- ions.},
	journal = {Biophysical journal},
	volume = {73},
	year = {1997},
	month = {1997 Oct},
	pages = {2097-105},
	abstract = {The binding of Zn2+ in Zn2+-regenerated bacteriorhodopsin (bR) was studied under various conditions by x-ray absorption fine structures (XAFS). The 0.9:1 and 2:1 Zn2+:bR samples gave similar XAFS spectra, suggesting that Zn2+ might have only one strong binding site in bR. It was found that in aqueous bR solution, Zn2+ has an average of six oxygen or nitrogen ligands. Upon drying, two ligands are lost, suggesting the existence of two weakly bound water ligands near the cation-binding site in bacteriorhodopsin. When excess Cl- ions were present before drying in the Zn2+-regenerated bR samples, it was found that two of the ligands were replaced by Cl- ions in the dried film, whereas two remain unchanged. The above observations suggest that Zn2+ has three types of ligands in regenerated bR (referred to as types I, II, and III). Type I ligands are strongly bound. These ligands cannot be removed by drying or by exchanging with Cl- ions. Type II ligands cannot be removed by drying, but can be replaced by Cl- ligands. Type III ligands are weakly bound to the metal cation and are most likely water molecules that can be removed by evaporation under vacuum or by drying with anhydrous CaSO4. The results are discussed in terms of the possible structure of the strongly binding site of Zn2+ in bR.},
	keywords = {Bacteriorhodopsins, Binding Sites, Biophysical Phenomena, Biophysics, Cations, Chlorides, Kinetics, Ligands, Spectrum Analysis, Water, X-Rays, Zinc, Zinc Compounds},
	issn = {0006-3495},
	doi = {10.1016/S0006-3495(97)78240-7},
	author = {Zhang, K and Song, Li and Dong, J and El-Sayed, Mostafa A}
}
@article {862,
	title = {Shape-Controlled Synthesis of Colloidal Platinum Nanoparticles},
	journal = {Science (New York, N.Y.)},
	volume = {272},
	year = {1996},
	month = {1996 Jun 28},
	pages = {1924-6},
	abstract = {The shapes and sizes of platinum nanoparticles were controlled by changes in the ratio of the concentration of the capping polymer material to the concentration of the platinum cations used in the reductive synthesis of colloidal particles in solution at room temperature. Tetrahedral, cubic, irregular-prismatic, icosahedral, and cubo-octahedral particle shapes were observed, whose distribution was dependent on the concentration ratio of the capping polymer material to the platinum cation. Controlling the shape of platinum nanoparticles is potentially important in the field of catalysis.},
	issn = {1095-9203},
	doi = {10.1126/science.272.5270.1924},
	author = {Ahmadi, Temer S. and Wang, Z.L. and Green, T.C. and Henglein, A. and El-Sayed, Mostafa A}
}
