Miniature seesaw to diagnose cancer?
Mechanical Engineering grad student Samira Faegh is attempting to revolutionize biosensor technology, which can be used in a variety of settings to detect anything from pathogens to blood glucose levels to molecular indicators of cancer. I sat down with her last week to talk about her research, which she’s been working on for about a year.
Faegh is in the IGERT Nanomedicine Program here at Northeastern, an NSF funded program that trains graduate students in applying nanotechnology to human health challenges. Like many IGERT projects, Faegh’s work bridges the gap between several disciplines.
She spent the first year of her PhD reading — scouring the literature for ideas in which she could merge her skills as a mechanical engineer with life science applications.
Most biosensors, she explained to me, use a laser to probe the material in question. They are expensive, bulky and complicated. Faegh wanted to design a system that would be cheaper and smaller, something you could put in your pocket and use on the go.
So, how does hers work? What makes it so special? Faegh’s device uses a “micro-cantilever,” a tiny vibrating bar connected to two electrodes. The bar is covered in a receptor biomolecule and is then dipped into a sample solution (eventually that solution would be a blood sample). If the receptor is glucose oxidose (which is what Faegh’s been using so far), it will bind to any glucose in the sample.
Next, Faegh applies a voltage to the system through the electrode and the bar begins to vibrate. The rate of vibration, which depends on how much binding has occurred, then sends a signal back to the electrode for a read out.
Faegh’s current research is to confirm that the mechanism works. Next she will try to improve the technology and then eventually use it to test real blood samples.
Since this work is so interdisciplinary, moving beyond just the mechanical engineering Faegh is familiary with, IGERT is a great way for her to be in touch with the experts she needs. “If I’m going to switch to DNA, we know a DNA person. And if we want to develop a gas sensor, then we can contact that person.”
Photo courtesy of Samira Faegh