Researchers at the University of Georgia (UGA) in the US have developed a low-cost diagnostic method, using gold nanoparticles, to diagnose flu in minutes.
Getting a quick and accurate diagnosis is critical during flu outbreaks. However, until now, physicians and health authorities have had to choose between a highly accurate yet time-consuming test and a rapid but error-prone test.
One of the UGA researchers Ralph Tripp, says: "We have known for a long time that we can use antibodies in order to capture viruses and that nanoparticles have different traits based on their size. What we have done is combine the two to create a diagnostic test that is rapid and highly sensitive."
Working at the UGA Nanoscale Science and Engineering Centre, Tripp and his colleague Jeremy Driskell linked immune system proteins known as antibodies with gold nanoparticles. The gold nanoparticle-antibody complex aggregates with any virus present in a sample, and a commercially available device measures the intensity with which the solution scatters light.
Driskell explains that gold nanoparticles, which are approximately a 10th of the width of a human hair, are extremely efficient at dispersing light. On the other hand, biological molecules such as viruses are intrinsically poor at scattering light. The clustering of viruses with gold nanoparticles is the reason why scattered light fluctuates in a predictable and measurable pattern.
According to the researchers, the test can be done literally at the point of patient care. "You only need to take a sample, put it in this instrument, press a button and get the results."
Gold is an expensive metal. However, the new diagnostic test uses such a very small amount – less than what would fit on the head of a pin – that the cost per test is about 0.05p.
This is a translation of an article first published by El Mundo