Working For A Purpose: Antibacterial nanosilver particles causing water pollution?
Christina Arnaout is a second year graduate student at Duke University. Working in Hudson Hall means that she’s doing something with Civil and Environmental Engineering, which is absolutely right! Under Dr. Claudia Gunsch, Christina is working on her dissertation, which is currently titled as: “Growth Inhibition of Diverse Wastewater Microbial Communities and the presence of Silver Resistance Genes.” Her main objective is to study if silver nanoparticles have any negative effects on wastewater treatment systems by altering the growth of vital microbial communities that cleanse the water. She hypothesizes that due to the presence of nanosilver particles in our waste water, which are there due to nanosilver products, the silver kills all the bacteria, including the ‘beneficial’ microorganisms that are used to clean the waste water. This in result creates water pollution!
A wastewater treatment plant. Christina's research will help prevent water pollution due to nanosilver particles.
My project is a tiny segment of Christina’s GIGANTIC research. It will be conducted at a much smaller scale (Petri dish….). The objective of my study is to characterize if nanosilver consumer products are truly antimicrobial. To do this, I am to characterize the antibacterial properties of nanosilver consumer products. This will be done by completing a zone of growth inhibition test on pure culture LB and R2A agar plates which has been streaked with E.coli. Characterizing the effects of nanosilver on microbial communities will clarify the need for additional treatment of wastewater pollute with nanosilver. If you were wondernig, the nanosilver is extracted by leaching the particles out. For example, I had to collect a small sample of nanosilver teddy bear and put it into a bottle of nanopure water. By placing this bottle onto a shaker table for 24 hours, I expect to find nanosilver particles in the water.
A zone of inhibition of bacterial growth. This is what I will be seeing when I finish conducting my experiment.
I’m so glad that my project will be useful to the human society, that is through Christina. She will analyze my data and from it, learn how E.coli reacts with the various nanosilver products I will be experimenting with. Brook, my lab partner, will be doing the same experiment, except, he will be streaking his agars with Bacillus, a different type of bacteria. Since there are many different microbial communities in waste water, it is essential to conduct experiments with various types of bacteria.
