New Haven, Conn. Yale scientists have created nanowire sensors coupled with simple microprocessor electronics that are both sensitive and specific enough to be used for point-of-care (POC) disease detection, according to a report in Nano Letters.
The sensors use activation of immune cells by highly specific antigens signatures of bacteria, viruses or cancer cells as the detector. When T cells are activated, they produce acid, and generate a tiny current in the nanowire electronics, signaling the presence of a specific antigen. The system can detect as few as 200 activated cells.
In earlier studies, these researchers demonstrated that the nanowires could detect generalized activation of this small number of T cells. The new report expands that work and shows the nanowires can identify activation from a single specific antigen even when there is substantial background "noise" from a general immune stimulation of other cells.
Describing the sensitivity of the system, senior author Tarek Fahmy, Yale assistant professor of biomedical engineering, said:. "Imagine I am the detector in a room where thousands of unrelated people are talking and I whisper, 'Who knows me?' I am so sensitive that I can hear even a few people saying, 'I do' above the crowd noise. In the past, we could detect everyone talking now we can hear the few above the many."
According to the authors, this level of sensitivity and specificity is unprecedented in a system that uses no dyes or radioactivity. Beyond its sensitivity, they say, the beauty of this detection system is in its speed producing results in seconds and its compatibility with existing CMOS electronics.
"We simply took direction from Mother Nature and used the exquisitely s
|Contact: Janet Rettig Emanuel|