A team of scientists from the Ames Laboratory has developed a new method, called dynamic multiple equilibrium gradients, to detect and measure biological markers. The technology is based on the old-fashioned capillary electrophoresis, now with a twist:
“This method is hyperselective and we can design it to target specific analytes for separation,” said Ryszard Jankowiak, an Ames Lab senior scientist. “Running multiple electric field gradients can focus and move the analytes to the detection window at precisely defined times, creating signature ‘fingerprints’, which minimizes the probability of false positives.”
The advance makes it possible to detect the smallest traces of substances, such as the estrogen-derived conjugates and DNA adducts in human fluid samples that could serve as biomarkers in risk assessment of breast and prostate cancers…
Unlike traditional capillary electrophoresis, Jankowiak’s team, which includes Yuri Markushin and graduate student Abdulilah Dawoud, uses only low voltage, around 2kV or less. Another difference is in the way the voltage is applied. Tiny electrodes are microfabricated along the walls of the hair-like capillaries (or channels), in essence creating a complex grid of electrodes.
“Saw-tooth type waves are applied along the channel outfitted with electrodes,” Jankowiak explains. “The electrodes act as capacitors and the applied waveforms generate electric fields. The moving variable electric field gradients induce very efficient focusing and separation of analytes. The analytes move along the capillary and tend to concentrate at the various electric field gradients. By varying the amplitude of the electric field gradients, these concentration points can be fine-tuned, making it easy to separate and identify the specific analytes.”
For now, we’ll have to wait and see how this technology makes it to applications in “chemical, biological and biomedical sciences, as well as in environmental monitoring, biological warfare detection, drug discovery, and more.” Sounds quite promising.
The press release…
