Detecting lethal diseases with rust and sand

January 31, 2011

The next big thing in medical diagnostics could be minutes particles of rust, iron oxide, coated with the material from which sand is formed, silicon dioxide. These magnetic nanoparticles, a mere 29 to 230 nanometers across, can be used to trap antibodies to the virus that causes cervical cancer and to the bacteria that causes potentially lethal diarrhea.

According to scientists in Vietnam, it is relatively straightforward to immobilize on nanoparticles, synthetic or that respond to the human papilloma virus, HPV18, and the toxic gut microbe Escherichia coli O157:H7. Once trapped in this way the antibodies can be exposed to a potentially contaminated sample. If pathogen particles are present some will stick to the antibodies and this change can then be detected by a conventional test, or assay. Conventional techniques without the benefit of nanoparticles can be accurate, but the improve the limits of detection by allowing just these particles to be separated from the sample before carrying out the assay so that residual cells and other substances do not interfere with the test.

E. coli could be detected if it is present in a sample at much lower numbers of than normal allowing contamination to be traced back to source with potentially much greater precision and faster. The improved detection limit for the presence of HPV18 in cells of the cervix could offer a way to screen for cancer of this tissue that reveals problems sooner than standard screening tests and so improve the chances of successful treatment for .

Tran Hoang Hai of the Ho Chi Minh City Institute of Physics and colleagues explain how cervical cancer is the second most common cancer after breast cancer in women worldwide, but the conventional enzyme-linked immunosorbent assay (ELISA) diagnosis does not reveal the presence of at the very earliest stage. The magnetic nanoparticle approach could remedy this situation.

Similarly, E. coli O157:H7 is an increasingly common cause of severe diarrhea, which can also lead to kidney failure and sometimes death. Infection spreads very quickly through ingestion of contaminated material, whether food or fecal matter, so a rapid test that can spot contamination early is essential for halting the spread of the disease.

Explore further: Magnetic nanoparticles detect and remove harmful bacteria

More information: "Immobilising of anti-HPV18 and E. coli O157:H7 antibodies on magnetic silica-coated Fe3O4 for early diagnosis of cervical cancer and diarrhea" in Int. J. Nanotechnol, 2011, 8, 383-398

Related Stories

Magnetic nanoparticles detect and remove harmful bacteria

November 19, 2007

Researchers in Ohio report the development of magnetic nanoparticles that show promise for quickly detecting and eliminating E. coli, anthrax, and other harmful bacteria. In laboratory studies, the nanoparticles helped detect ...

Labeling Cells with Magnetic Nanoparticles

February 20, 2007

Investigators at the German Cancer Research Center have developed silica-coated iron oxide nanoparticles that allow for cell tracking in a live animal using magnetic resonance imaging (MRI). More sensitive methods for tracking ...

Recommended for you

Atomic blasting creates new devices to measure nanoparticles

December 14, 2017

Like sandblasting at the nanometer scale, focused beams of ions ablate hard materials to form intricate three-dimensional patterns. The beams can create tiny features in the lateral dimensions—length and width, but to create ...

Engineers create plants that glow

December 13, 2017

Imagine that instead of switching on a lamp when it gets dark, you could read by the light of a glowing plant on your desk.

Faster, more accurate cancer detection using nanoparticles

December 12, 2017

Using light-emitting nanoparticles, Rutgers University-New Brunswick scientists have invented a highly effective method to detect tiny tumors and track their spread, potentially leading to earlier cancer detection and more ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.