U.S.-Egypt Cooperative Research: Chemical Synthesis of Magnetic Oxide Nanoparticles and Films, and Their evaluation for Sensing Applications.

University Of Maryland, College Park, College Park MD

Investigators

Abstract

0612150 Venkatesan Description: This award is to support a cooperative research by Dr. T. Venkatasen, Department of Physics, University of Maryland, College Park,Maryland and Dr. Wegdan Ramadan Osman, Alexandria University, Alexandria, Egypt. They plan to conduct research on the chemical synthesis of magnetic oxide nanoparticles both in the powder form and in the form of supported nanoparticle films. Intellectual Merit: There has been a surge of activity, over the past few years, in the field of new functional magnetic oxides such as colossal magnetoresistance manganites, multiferroics and diluted magnetic semiconductors due to their projected potential for a number of novel applications. The key issues are the interplay of geometric and physical length scales via the influence of finite system size and small number statistics on the structural and electronic property relaxations. It has been widely demonstrated that reduction in the system size below a certain system-dependent limit introduces changes in its physical properties and endows it with an entirely new property-space. This calls for examination of the application potential of the nanoscale materials. Magnetic nanomaterials are characterized by new and partially unexpected magnetic properties, such as, for example, enhanced remanence or a giant coercive field. Furthermore, the magnetization curve, which is a picture of the extrinsic behavior of a magnetic material, may depend on the system size. Nanoscience is an intriguing admixture of the science of the constituent and the system. This research aims at elucidating these phenomena and developing means to control them in the interest of applications. The PIs will explore sensing applications which could be of broader use in fields such as geology, environment, and agriculture. Broader Impact: Magnetic nanoparticles offer several interesting possibilities in the field of biomedicine and the related science. The broad and controllable range of their size from 1-100 nanometers allows their tagging to biological objects such as cells, viruses, proteins or genes. Moreover, they can be manipulated by an external magnetic field gradient. Given the intrinsic penetrability of magnetic fields into human tissue, thus enabling the transport, immobilization and control of the magnetic nanoparticles or the corresponding tagged biological entities. Also, the resonant response of magnetic nanoparticles to time-varying magnetic field causes significant transfer of energy from the exciting field to the nanoparticle, resulting in their heating and making possible their use as hyperthermia agents. Thus these particles can be made to deliver localized thermal energy to targeted bodies such as tumors; or as chemotherapy and radiotherapy enhancement agents. Magnetic nanoparticles and related fluid systems are being actively investigated in the context of four specific applications: magnetic separation, drug delivery, hyperthermia treatments and magnetic resonance imaging (MRI) contrast enhancement. Many other applications of magnetic nanoparticles have been envisaged in diverse fields such as agriculture, oil explorations. This project is being supported under the US-Egypt Joint Fund Program, which provides grants to scientists and engineers in both countries to carry out these cooperative activities.