Science Buddies: "Ask an Expert"

Hello,

I am just coming up with a topic for a science project and one idea I had was to use magnetic core polyethylene microbeads to absorb pesticides in water and then be magnetized out. I plan to mix pesticides and water to a certain known concentration, and add in the microbeads and let them sit for a couple of months. Then, I plan to remeasure the concentration of the pesticides in the water again, to determine how much of the pesticides was absorbed by the microbeads. However, I cannot find a way to measure the concentration of pesticides in water without any high tech lab equipment. Is there any easier way to measure this, or is there a way around this issue?

Thank you very much.

Hi Matthew,

That sounds like a great idea for a project! We use magnetic beads in the lab with antibodies attached to them to select certain types of cells and they work very well. I know that there a many different kinds of microbeads made from different materials and surface-modified in various ways. Do you have beads that you know will bind a certain kind of pesticide? What kinds of pesticide were you planning on testing?

Many pesticides such as Permethrin (https://en.wikipedia.org/wiki/Permethrin) are synthetic organic chemicals and detecting them in water would require fairly sophisticated instruments like UV spectrophotometers or high-performance liquid chromatographs (HPLC). Many university molecular biology or chemistry labs have a UV-spec, so if you have a friend who works in such a lab they might be able to help you analyze your samples.

Let us know more specifically what you are interested in and we will try to help you in planning and executing a great project.

Good luck!

Sybee