Publication Date

2017

Document Type

Dissertation

Committee Members

Norma Adragna (Committee Member), David Dolson (Committee Member), Steven Higgins (Committee Member), Mill Miller (Committee Member), Ioana Sizemore (Committee Chair)

Degree Name

Doctor of Philosophy (PhD)

Abstract

Advancements in the nanotechnology have taken a huge leap in 21st century resulting in 1814 consumer products containing nanomaterials. About 47% of these products belong to the health and fitness sector and ~24% utilize silver nanoparticles (AgNPs). Despite the promising biomedical applications of AgNPs (e.g. bone cements, contrasting agents, and drug-carriers), lack of standardized methods for examining their nanokinetics (i.e., Absorption, Distribution, Metabolism, and Elimination (ADMEs)) limit their clinical implementation. The current work addresses this knowledge gap by developing analytical-based approaches for studying in vitro ADMEs of AgNPs. To demonstrate the versatility of these methodologies, two in vitro kidney study models (Vero 76 and HEK 293 cells) were tested under pre-determined exposure concentrations (3-300 µg mL-1) and times (4-48 hr). The ADMEs of both AgNPs+ and AgNPs- in Vero 76 cells were summarized here for illustrative purposes: [A]: Inductively coupled plasma optical emission spectroscopy (ICP-OES) facilitated the evaluation of critical kinetic parameters including order of reaction, rate constant and bioavailability (first-order, kabs= 0.05 hr-1, Cmaximum < 20.7±4% and Tmaximum > 48 hr), [D] CytoViva and Raman imaging outlined the uptake and cellular localization patterns (e.g., Raman results of mapped cells exposed to AgNPs+ and AgNPs- were dominated by the signals corresponding to the plasma membrane and cytoplasm, respectively), [M] Cloud point extraction (CPE) followed by tangential flow filtration enhanced the separation of two Ag species from the cellular matrix (= 11±4% of the AgNPs were converted to Ag+), and [E] ICP-OES also facilitated the construction of clearance-time curves to evaluate the elimination kinetics of sub-lethal AgNPs (first-order, keli=0.039 hr-1). Furthermore, a new laboratory module was developed according to the five essential features laid by the National Research Council for inquiry-based teaching and learning in order to introduce undergraduate and graduate students to the fabrication and characterization of green and non-green silver and gold nanoparticles. As demonstrated by the results of the formative assessments, this hands-on laboratory was not only well-received by students from diverse backgrounds, but also stimulated their critical thinking and helped them acquire new laboratory skills.

Page Count

146

Department or Program

Biomedical Sciences

Year Degree Awarded

2017

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