Easier, better, inexpensive testing ... with the naked eye

Researchers in London have developed an "ultra-sensitive sensor" that could make it easier to detect diseases earlier--and with the naked eye. The new technology could be relatively inexpensive, offering the possibility of greater access to early diagnoses such as HIV and prostate cancer in countries short on resources.

The team, from the Department of Materials at Imperial College London, say the visual sensor technology is 10 times more sensitive than the most sensitive current technology, according to an announcement

In their study, they used it to detect a biomarker called p24 in serum from blood samples, which indicates HIV infection and also prostate specific antigen (PSA), which is an early indicator for prostate cancer.  The test is done in a disposable container. When the result is positive, a reaction generates irregular clumps of nanoparticles and the solution turns blue. If it's negative, the nanoparticles are ball-shaped and the solution turns red. The work is published at Nature Nanotechnology.

"We have developed a test that we hope will enable previously undetectable HIV infections and indicators of cancer to be picked up, which would mean people could be treated sooner," said co-author Dr. Roberto de la Rica. "We also believe that this test could be significantly cheaper to administer, which could pave the way for more widespread use of HIV testing in poorer parts of the world."

The team's next steps will be working with nonprofit health organizations for guidance on funding, manufacturing and distributing the sensors to the developing world.

In the race to develop low-cost diagnostics, efforts increasingly focus on smartphones, which often are common in developing countries when other forms of technology aren't. A smartphone-enable blood-testing system developed at the University of Rhode Island could reduce the researchers could reduce the wait for test results from days to minutes, the researchers say.

Other British research could put an affordable, hand-held diagnostic device into a care provider's hands that could help fight drug-resistant malaria by identifying the strain.

Still other research from MIT requires only a minute blood sample. That early research  on microchip technology and the concept that balls moving through fluid lose speed as they grow larger. Oscillating magnetic beads can be "read"  to determine whether they have grown by attaching to a target biomolecule rather than being sent to a lab for analysis.

To learn more:
- read the announcement
- here's the abstract