A tiny drop of blood. One day that may be all a device needs to screen for hundreds of cancer markers and viral infections. Richard Roberts partners with electrical engineers to help create such cutting-edge diagnostic technologies.
Roberts designs proteins using a technique he invented more than a decade ago. He pours a collection of approximately 10 trillion protein sequences over a target such as a virus strain to see which molecules stick. After six or seven cycles, the sequences are culled down to a single molecule that becomes the predominant component of the final mixture.
Roberts’ engineering collaborators then construct a microscale sensory device using the protein. When the reagent attaches to a viral or cancer cell in a blood sample, it subtly changes the electrical properties of the wire it’s attached to and a signal is emitted. Mark Thompson and Chongwu Zhou, who hold joint appointments in the College and USC Viterbi, are among those with whom Roberts joins forces. Thompson focuses on the microfluidic part of the device and Zhou on the nanosensor material.
“I think this kind of teamwork is characteristic of what’s happening in biology today,” said Roberts, who holds a joint appointment in the College’s Department of Chemistry and USC Viterbi’s Monk Family Department of Chemical Engineering and Materials Science. “There are people who make stuff, in our case proteins, and it’s interesting to try to use those in devices that actually have some kind of impact.”
With the support of the National Institutes of Health’s Roadmap Transformative Research Projects Program, Roberts is investigating ways to automate his protein design method to maximize a diagnostic device’s capabilities. Roberts and his fellow researchers in University of California, Los Angeles’ Department of Medical Pharmacology and University of California, Santa Barbara’s Department of Electrical Engineering hope to craft technology that would condense several cycles of purification down to one. This would allow Roberts to fashion hundreds of proteins that could be deployed in a single chip to simultaneously run tests for hundreds of different viruses or cancers.
“The core of much new science takes technologies from many different areas and puts them together toward some useful end,” Roberts said. “The results are often much greater than the sum of the parts.”
Read more articles from USC College Magazine’s Spring/Summer 2010 issue.