Science Buddies: "Ask an Expert"

Hi all,

I am doing a science experiment testing the effects of phytoremediation. I am using Indian mustard seeds in copper sulfate solutions to see how the seeds reduce the concentration of copper. The only problem is that I don't know what concentrations of copper to use. At first I wanted to use concentrations of 0,50, 100, and 150 ppm as indicated in this study http://research.sc.chula.ac.th/31-1e/pa ... iyanan.pdf but I can't find a test kit that measures that high.

Most test kits online only measure up to 10 ppm. Should I just lower my copper concentrations to 0, 1, 2, and 3 ppm? I'm worried that these low concentrations will not yield good data. Can anyone please help me find a good way to accurately measure the copper concentrations without breaking the bank? I would really appreciate it.
Thanks!!

Hello there,

I don't know much about measuring copper concentrations, but I may suggest also posting this to the physical sciences thread because there are potentially chemists, biochemists, or engineers in those threads that may be able to provide more insight into this problem.

I hope you are able to find help!

Best,
Connie

thank you!

Hi Ari,

If you want to use higher concentrations of copper and assay them with the available kits, there's really no problem. All you would have to do is dilute your sample with water before you assayed it. For example, if the maximum Cu2+ concentration your test kit can handle is 10 ppm and you are using a 150 ppm solution, just mix one part of your solution with 14 parts of water.

You will have to do some test dilutions first to make sure you can measure your Cu solutions OK, but I don't see why it shouldn't work. To get the actual concentration you just have to multiply the assay value by the dilution factor. If you diluted your sample 1:15, then multiply your result by 15.

Sybee

Sybee,

Thank you so much! I never thought of it that way. You are a life saver!

Thanks for the kind words, Ari! I am happy my suggestion helped. Keep posting on this same thread and we will continue to mentor you through the project. These are really interesting and important experiments and citizen-scientists can really play a part in the investigation.

Best wishes,

Sybee