Funded by an Ohio Sea Grant development grant, Dr. Chris Spiese of Ohio Northern University (ONU) is working on a new method for rapid phosphate detection that promises to be both cheaper and faster than the currently used method. Phosphate is the most common form of environmental phosphorus, and most phosphate enters Lake Erie through agricultural runoff, where it can fuel harmful algal blooms, so watershed managers need to be able to monitor levels easily and cost-effectively.
“The traditional detection method for phosphate is kind of cumbersome”? explains Spiese — each sample can cost about $50 to test. “Our goal was to find a better, faster, cheaper method of measuring phosphate.”?
Spiese and undergraduate student Joanne Berry are working with a compound that reacts to the presence of phosphate by quickly producing yellow-green fluorescence, which can then be detected with standard lab equipment. To find this particular molecule, they created six versions of a compound presented in a 2011 journal article, and tested each for reactivity with phosphate as well as for interference from other common materials present in water samples.
The researchers were able to rule out interactions with organic acids found in most natural waters, with major ions like carbonate, sulfate, and chloride, and with silicate and arsenate, two compounds that can interfere with the traditional testing method. “We got down to the point where we were struggling to find compounds that would actually interfere”? says Spiese, Assistant Professor in the Department of Chemistry & Biochemistry at ONU.
As desired, in addition to that specificity, the method is much cheaper than the current test. Once the protocol is perfected and published, Spiese will provide it to the Ohio EPA for further evaluation and potential adoption. The researchers expect to submit a journal article outlining their procedure in early summer of 2013.
Spiese also plans to involve volunteers from the Blanchard River Watershed Partnership and local high schools in a one-day sampling effort this spring to create a snapshot of nutrient levels across the watershed. Volunteers will take samples that will then be returned to Spiese’s lab for testing using both the traditional technique and the faster, more cost-effective method.
“Our goal is to get sampling all along that watershed, and interface with local schools and the community to really get them involved, to get the students exposed to doing real environmental research”? says Spiese. “It’s going to be a blast if we can recruit enough people.”?
You can read more about this project in the Fall/Winter issue of Ohio Sea Grant’s Twine Line.
Ohio State University’s Ohio Sea Grant program is part of NOAA Sea Grant, a network of 32 Sea Grant programs dedicated to the protection and sustainable use of marine and Great Lakes resources. For more information, visit ohioseagrant.osu.edu.
Christina Dierkes, Ohio Sea Grant, firstname.lastname@example.org.