Gold leaf could combat the spread of sexually transmitted infections

BOSTON, Mass. — Artists and craftsmen use gold leaf in the creation of everything from art, to clothing, even to food. Now, scientists have discovered another use for the precious metal — stopping the spread of sexually transmitted infections.

Researchers in Boston say electrodes made of gold leaf are sensitive enough to detect the potentially deadly human papillomavirus (HPV). In combination with a gene editing technique, study authors could accurately detect the STI in swabs from patients.

Eight in ten cases of HPV and HIV occur in impoverished parts of the world like Africa and South America. This new test costs under $3, more than thirty times less than conventional methods.

“Early diagnosis is essential for managing HIV,” corresponding author Professor Catherine Klapperich of Boston University writes in the journal ACS Central Science. “Similarly, HPV causes nearly all cases of cervical cancer, the majority (90%) of which occur in low-resource settings.”

“Importantly, infection with HPV is six times more likely to progress to cervical cancer in women who are HIV-positive. An inexpensive, adaptable point-of-care test for viral infections would make screening for these viruses more accessible to a broader set of the population. An electrode made from from 24K gold leaf provided a readout – in the presence of HPV,” the researchers continue.

Building an STI sensor with simple household items?

The team was able to assemble their sensor using just a sheet of 24K gold leaf, an adhesive, a stencil, and a razor blade. On the surface, they attached strands of amplified DNA tagged with a dye. The virus triggers a protein that “snips” genes, changing the electrochemical signal.

Researchers add this device can also be adapted to detect any infection, including COVID-19. Developing nations often lack the facilities, trained personnel, and money to conduct common antibody and PCR (polymerase chain reaction) tests themselves.

“Sexually transmitted infections (STIs) affect millions of people per year and constitute a global health crisis,” Prof. Klapperich says in a statement to SWNS. “Infection with HPV causes nearly all cases of cervical cancer, which is the fourth-most common cancer in women globally. This form of cancer can be easily cured if diagnosed and treated early.”

The World Health Organization has described it as a “silent epidemic.” One in 25 people has at least one STI at any one time.

In the United States, the CDC reports there were 26 million new STI cases in 2018 alone. Nearly half of new cases are among children and young adults between 15 and 24 years-old.

SWNS writer Mark Waghorn contributed to this report.