Photo by Juan D. Alfonso
A new approach to urine testing could make the tests more versatile and therefore decrease the need for blood tests, according to researchers.
They believe the method could also reduce costs, produce results faster than current tests, and lower the volume of urine needed for a sample.
R. Kenneth Marcus, PhD, of Clemson University in South Carolina, and his colleagues described this method in Proteomics-Clinical Applications.
Dr Marcus noted that the trouble with testing urine is that it’s awash in salt, so it can be tricky to isolate the proteins that act as biomarkers.
To overcome this problem, he and his colleagues used a string made of capillary-channeled polymer fibers. The team packed the fibers into plastic tubes and then passed urine samples through the tubes by spinning them in a centrifuge for 30 seconds.
Then, the researchers ran de-ionized water through the tubes for a minute to wash off salt and other contaminants.
As proteins are hydrophobic, they remained stuck to the fibers. The team extracted the proteins by running a solvent through the tubes in the centrifuge for 30 seconds.
When this process was complete, the researchers were left with purified proteins that could be stored in a plastic vial and refrigerated until testing time.
The team was able to extract 12 samples in about 5 minutes, limited only by centrifuge capacity.
In addition to being faster and cheaper than current urine tests, the new testing method should also make it easier to test urine samples from infants, Dr Marcus said.
One of the challenges now is getting a large enough sample, but the new method requires only a few microliters of urine.
