Elucidating the Impact of Engineered Nanoparticles on Microbial Organisms in the Environment

Date of Award


Degree Name

Doctor of Philosophy



First Advisor

Dr. Sherine O. Obare

Second Advisor

Dr. Ekkehard Sinn

Third Advisor

Dr. Donald Schreiber

Fourth Advisor

Dr. Charles Ide


Engineered nanoparticles, iron oxide nanoparticles, humic acid, DNA damage, bacteria, plasmonic nanoparticles


Due to the increased manufacturing of engineered nanoparticles (ENPs) and their inclusion in consumer products, their presence in the environment is a growing concern. This dissertation focuses on two classes of nanoparticles: plasmonic nanoparticles consisting of monometallic silver (Ag), monometallic gold (Au) and bimetallic silver-gold (Ag-Au) engineered nanoparticles, and iron oxide nanoparticles (IONPs). The goal of the work in this dissertation is to understand the impact of ENPs on chemical and biological contaminants. The first half of the dissertation focuses on the use of plasmonic nanoparticles toward the detection of toxic organophosphorus pollutants, accompanied by understanding the stability of ENPs in environments with excess pesticide residues. The second half of the dissertation focuses on IONPs, which are produced due to their favorable magnetic, catalytic, biomedical, and electronic properties. The increase in manufacturing and use of IONPs has led to their unintentional release into the environment. It is important to take proactive measures to understand the impact of IONPs and other nanoparticles on the environment and on biological species particularly because of the increased chemical reactivity of nanoparticles relative to their bulk counterparts. The work in this dissertation aims to understand the influence of IONPs on microorganisms, with an emphasis on those required for bioremediation. The IONPshave been found to exert severe genotoxicity by entering the cell and interacting with the nucleus, consequently leading to DNA abnormalities and aberrations. The results shed light on the transformations that IONPs undergo in the environment, the genotoxic effect on biological cells, and the impact on the ecosystem.

Access Setting

Dissertation-Abstract Only

Restricted to Campus until


This document is currently not available here.