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The first objective is to provide an understanding of fundamental nanoscale phenomena and processes. <P>The second objective is to develop and characterize nanomaterials. <P>The third objective is To develop nanoscale devices and systems. <P>The fourth objective is to provide an understanding of economic, environmental, safety and health impacts of nanotechnology in agricultural, food and biological systems. <P>The last objective is to develop educational and outreach programs on the use and impacts of nanotechnology in food, agricultural and biological systems.
Non-Technical Summary: Food toxins, pathogens, and other contaminants should be detected easily by persons with little or no training. We will develop a sensor which will change its color in the presence of a food contaminant. <P> Approach: We will use the chromogenic effect of gold nanoparticles and latex microsphere conjugation. The gold nanoparticles are pinkish red; the latex microspheres are white. When gold nanoparticles are attached to the latex microspheres, the latex acquires the color of the gold nanoparticles. If the gold particles are displaced by an analyte molecule of interest (e.g., food toxin), the latex particles reacquire white color. This visible color change will form the basis for our nanobiosensor. We will also investigate the interference effect of large molecules blocking the light reaching the latex particles and hence rendering them white.