Salt in urine helps conduct electricity but also makes it challenging for typical biosensors to differentiate the "signals" of cancer molecules from "noise" around them in the electrodes. The UC Irvine team developed a new type of sensor: They added nanoscale protein receptors to tiny, pencil-like viruses called phages that live only within bacteria. Double wrapping the phages with additional receptors greatly increases the capture and transmission of cancer molecule signals.
"We add a high concentration of the viruses, and they get trapped directly in the electrode. We're jamming the signal with the cancer marker, and it stays on louder than all the other material," said lead author Kritika Mohan, a graduate student with Weiss' lab. "To our surprise, it works really well in the ingredients that make up urine."
The next step is human clinical trials, which the researchers hope can be conducted fairly quickly since the testing will be noninvasive. The method has been patented and licensed, and a commercial partner has been identified.
Ultimately, the scientists aim to capitalize on related nanowire research to design invisible filaments that could carry cancer signals to a smartphone or other electrical device. Software would notify users whether they're in the safe range or should contact a physician.
Other prostate cancer tests coming to market cost up to $4,000 each. The UC Irvine team made price a key design factor of their work.
"The manufacturing costs would be low, because the material costs are very, very low. The receptors for recognizing the cancer markers are really inexpensive to make. That's why we chose these viruses," Weiss said. "They're grown in a yeasty, brothy solution kind of like chicken broth that could easily be mixed on a huge scale."
He added that the receptors are also "incredibly tough." They don't need to be refrigerated and can
|Contact: Janet Wilson|
University of California - Irvine