New method may lead to faster diagnosis of HIV

Washington: Scientists have developed a new method for medical testing which may lead to faster diagnosis of HIV, Lyme disease, syphilis, rotavirus and other infectious
conditions.

Researchers combined cutting-edge nanoscience with a magnetic phenomenon discovered more than 170 years ago to create the method for speedy medical tests.
"I see no reason why a variation of this technique could not be in every hospital throughout the world," said Shawn Putnam, an assistant professor at University of Central Florida in the US.

The discovery, if commercialised, could lead to faster test results for HIV, Lyme disease, syphilis, rotavirus and other infectious conditions, researchers said. At the core of the research are nanoparticles - tiny particles that are one-billionth of a meter, they said.
The team coated nanoparticles with the antibody to BSA, or bovine serum albumin, which is commonly used as the basis of a variety of diagnostic tests.

By mixing the nanoparticles in a test solution - such as one used for a blood test - the BSA proteins preferentially bind with the antibodies that coat the nanoparticles, like a
lock and key. That reaction was already well known. However, Putnam's team came up with a novel way of measuring the quantity of proteins present. He used nanoparticles with an iron core and applied a magnetic field to the solution, causing the particles to align in a particular formation.

As proteins bind to the antibody-coated particles, the rotation of the particles becomes sluggish, which is easy to detect with laser optics. The interaction of a magnetic field and light is known as Faraday rotation, a principle discovered by scientist Michael
Faraday in 1845. Putnam adapted it for biological use. "It's an old theory, but no one has actually applied this aspect of it," he said.

Other antigens and their unique antibodies could be substituted for the BSA protein used in the research, allowing medical tests for a wide array of infectious diseases.
The proof of concept shows the method could be used to produce biochemical immunology test results in as little as 15 minutes, compared to several hours for ELISA, or enzyme-linked immunosorbent assay, which is currently a standard approach
for biomolecule detection.The research was published in the journal Small.