Developing a Nanoparticle Based Antimicrobial

Research abstract

Antibody coated magnetic iron oxide nanoparticles (NanoProbes) will be targeted to specific bacterial strains in vitro and tested as a potential therapeutic. An oscillating magnetic field will be applied to cultures mixed with NanoProbes, generating local thermal energy at the surface of the bacterial cells. The disruption of cell membranes due to the thermal and mechanical energy produced will be quantitatively determined using fluorescent assays. Survival of the bacterial population will be tested by serially diluting, spot plating and counting for CFU (colony forming units). The Nanoprobes will also be tested for their ability to potentiate the activity of various antibiotics. This strategy has exciting implications since bacterial infections are known to be notoriously recalcitrant. Biofilm infections in particular are difficult to sterilize due to a small subpopulation of persister cells, which are tolerant to antibiotics. These cells are phenotypic variants in a state of dormancy, which affords them tolerance to high doses as well as combinations of antibiotics. Thermal disruption by NanoProbes is particularly exciting because the strategy aims to disrupt bacterial cells regardless of their metabolic state. The technique has the potential of sterilizing infections by killing not only the bulk of the population but the tolerant persister fraction.

Research activities/experience

Research activities involved will include developing and testing protocols to conjugate bacteria specific antibodies to magnetic iron oxide nanoparticles. In vitro testing of nanoparticle coated bacterial cell survival to an oscillating magnetic field will also be carried out. Other possible experiments may include the production of iron oxide nanoparticles, TEM (Transmission Electron Microscopy) analysis, and zeta potential analysis of nanoparticles.

Expectations

RET participants will be expected to learn standard sterile microbiological techniques and spend time researching literature related to their project. Participants will be taught all necessary skills but the ability to work independently will be expected. Research will focus more on microbiological experiments than nanoparticle technology. Applicants should have an interest in microbiology but a significant background will not be expected.


Suggested literature to be reviewed by RET/YSP prior to beginning this research assignment

Brock Biology of Microorganisms. Madigan, Martinko, Parker. Tenth Edition. Prentice Hall, 2003.
Chapter 2: An Overview of Microbial Life
Chapter 4: Cell Structure/Function
Chapter 6: Microbial Growth
Chapter 20: Microbial Growth Control

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