Ivan H. El-Sayed

Learn More
Due to strong electric fields at the surface, the absorption and scattering of electromagnetic radiation by noble metal nanoparticles are strongly enhanced. These unique properties provide the potential of designing novel optically active reagents for simultaneous molecular imaging and photothermal cancer therapy. It is desirable to use agents that are(More)
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(More)
The use of lasers, over the past few decades, has emerged to be highly promising for cancer therapy modalities, most commonly the photothermal therapy method, which employs light absorbing dyes for achieving the photothermal damage of tumors, and the photodynamic therapy, which employs chemical photosensitizers that generate singlet oxygen that is capable(More)
The selection of nanoparticles for achieving efficient contrast for biological and cell imaging applications, as well as for photothermal therapeutic applications, is based on the optical properties of the nanoparticles. We use Mie theory and discrete dipole approximation method to calculate absorption and scattering efficiencies and optical resonance(More)
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(More)
PURPOSE To report the clinical outcome of patients treated with intensity-modulated radiation therapy (IMRT) for malignancies of the nasal cavity and paranasal sinuses. METHODS AND MATERIALS Between 1998 and 2004, 36 patients with malignancies of the sinonasal region were treated with IMRT. Thirty-two patients (89%) were treated in the postoperative(More)
Noble metal nanostructures attract much interest because of their unique properties, including large optical field enhancements resulting in the strong scattering and absorption of light. The enhancement in the optical and photothermal properties of noble metal nanoparticles arises from resonant oscillation of their free electrons in the presence of light,(More)
Plasmonic photothermal therapy (PPTT) is a minimally-invasive oncological treatment strategy in which photon energy is selectively administered and converted into heat sufficient to induce cellular hyperthermia. The present work demonstrates the feasibility of in vivo PPTT treatment of deep-tissue malignancies using easily-prepared plasmonic gold nanorods(More)
Recent years have seen tremendous progress in the design and study of nanomaterials geared towards biological and biomedical applications, most notable among these being the noble metal nanoparticles. In this review, we outline the surface-plasmon resonance-enhanced optical properties of colloidal gold nanoparticles directed towards recent biomedical(More)
Resonant electron oscillations on the surface of noble metal nanoparticles (Au, Ag, Cu) create the surface plasmon resonance (SPR) that greatly enhances the absorption and Rayleigh (Mie) scattering of light by these particles. By adjusting the size and shape of the particles from spheres to rods, the SPR absorption and scattering can be tuned from the(More)