Post by williamplayer on Jan 15, 2015 14:21:30 GMT
Engineers develop graphene-based biosensor that works in three ways at once
The researchers' biosensor has mechanical, electrical and optical modes.
The researchers' biosensor has mechanical, electrical and optical modes.
One of nanotechnology's greatest promises is interacting with the biological world the way our own cells do, but current biosensors must be tailor-made to detect the presence of one type of protein, the identity of which must be known in advance.
University of Pennsylvania engineers have now devised a new kind of graphene-based biosensor that works in three ways at once. Because proteins trigger three different types of signals, the sensor can triangulate this information to produce more sensitive and accurate results. By taking advantage of the unique integration of multiple physical sensing modes on the same chip, this sensor device can extend the protein-concentration sensing range by a thousand-fold.
This extended range could be particularly useful in early diagnosis of certain cancers, where the blood biomarker concentration varies by orders of magnitude from patient to patient. The ability to make multiple detections of the same biomarker on the same chip also has the potential to reduce false positives and negatives in medical diagnostic tests.
Eventually, such a technique could be used in an all-purpose biosensor, which could identify a wide range of proteins through their mass, as well as their optical and electrical properties.
A biosensor that did not have to be fine-tuned to detect only specific proteins would have a host of biomedical applications in diagnostic devices.
The study, published in the journal Nano Letters, was conducted by Ertugrul Cubukcu, assistant professor in the departments of Materials Science and Engineering and Electrical and Systems Engineering in Penn's School of Engineering and Applied Science, and members of his lab, Alexander Y. Zhu, Fei Yi, Jason C. Reed and Hai Zhu.
"In a typical single mode biosensor you have two proteins that interact strongly. You attach protein A to your sensor and, when protein B binds to it, the sensor transduces that binding into some sort of electrical signal," Cubukcu said," But it's kind of a dumb sensor in that it can only tell you if that kind of binding has occurred.
READ FULL ARTICLE: phys.org/news/2015-01-graphene-based-biosensor-ways.html
University of Pennsylvania engineers have now devised a new kind of graphene-based biosensor that works in three ways at once. Because proteins trigger three different types of signals, the sensor can triangulate this information to produce more sensitive and accurate results. By taking advantage of the unique integration of multiple physical sensing modes on the same chip, this sensor device can extend the protein-concentration sensing range by a thousand-fold.
This extended range could be particularly useful in early diagnosis of certain cancers, where the blood biomarker concentration varies by orders of magnitude from patient to patient. The ability to make multiple detections of the same biomarker on the same chip also has the potential to reduce false positives and negatives in medical diagnostic tests.
Eventually, such a technique could be used in an all-purpose biosensor, which could identify a wide range of proteins through their mass, as well as their optical and electrical properties.
A biosensor that did not have to be fine-tuned to detect only specific proteins would have a host of biomedical applications in diagnostic devices.
The study, published in the journal Nano Letters, was conducted by Ertugrul Cubukcu, assistant professor in the departments of Materials Science and Engineering and Electrical and Systems Engineering in Penn's School of Engineering and Applied Science, and members of his lab, Alexander Y. Zhu, Fei Yi, Jason C. Reed and Hai Zhu.
"In a typical single mode biosensor you have two proteins that interact strongly. You attach protein A to your sensor and, when protein B binds to it, the sensor transduces that binding into some sort of electrical signal," Cubukcu said," But it's kind of a dumb sensor in that it can only tell you if that kind of binding has occurred.
READ FULL ARTICLE: phys.org/news/2015-01-graphene-based-biosensor-ways.html