Tova A. Samuels

Doctoral Dissertation Announcement

---

Candidate: Tova A. Samuels

Degree of: Doctor of Philosophy

Department: Chemistry

Title: Strategies for the Detection and Deactivation of Chemical and Biological Environmental Pollutants

Committee:
Dr. Sherine Obare, Chair
Dr. Carla Koretsky
Dr. Yirong Mo
Dr. Ekkehard Sinn

Date: Thursday, May 17, 2012 9:30 a.m. to 11:30 a.m.
2902 Wood Hall

Abstract:
Advances in the chemical, medical and agricultural fields have provided valuable products and resources for a global community. However, some of these advances have had a negative impact on the environment. Chemical and biological pollutants affect our food and water systems and consequently, our quality of life. Furthermore, pandemic diseases brought about by pathogenic bacteria are of growing concern as we now live in a global community and unexpected exposure is an inevitable possibility. The threat of pandemic diseases is compounded by factors such as the increase in intercontinental travel and commerce, and the expansion of antibiotic resistant among Gram-positive and Gram-negative microorganisms. Thus, new and effective methods to control microbial pathogens are critically needed. The rational design of materials that detect and/or remediate pollutants continue to be in high demand. This dissertation focuses on two classes of pollutants: (1) organophosphorus pesticides and (2) Gram-positive and Gram-negative bacteria. We have developed well-defined metallic and bimetallic nanoparticles based on silver (Ag), and gold (Au) metallic nanoparticles, and Ag/Au bimetallic nanoparticles. The interactions of the unfunctionalized metallic and bimetallic nanoparticles with organophosphorus pesticides were studied in an effort to develop a colorimetric detection system. Furthermore, by functionalizing the surface of metallic nanoparticles with an antibiotic, we have developed an effective method to overcome the antibiotic resistance of microbial pathogens. We show a comparative study for the antimicrobial effects of ampicillin functionalized Ag NPs and Au NPs, on clinical isolates of food and water borne pathogens. The design, synthesis, characterization and applications of the materials will be presented.