PHYSICS WORLD
Scientists in the UK and Spain have developed a new biological nanosensor that produces a stronger signal when its target molecules are lower in concentration. The sensor can reliably detect molecules at concentrations that are many orders of magnitude lower than can be detected by the diagnostic tests that are used in hospitals today, and could help to identify diseases in their earliest stages, when, in many cases, they are easier to treat and cure.
Conventional biosensors produce a signal that is in proportion to the concentration of target molecules, so at low concentrations they lose sensitivity and become susceptible to interference from other molecules. For disease biomarkers such as cancer antigens, the ability to differentiate confidently between a zero result and a trace result is critical.
The new sensor developed by Molly Stevens and colleagues at Imperial College London and the University of Vigo, Spain, can detect concentrations that are at least 10 times lower than the best existing ultrasensitive tests. “For many diseases, using current technology to look for early signs can be like finding the proverbial needle in a haystack,” says Stevens. “Our new test can actually find that needle.”
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