Medicinal uses of gold already save thousands of lives every year but new advances in technology and a burgeoning market means it’s increasingly likely it will one day save yours, too. Rachel England investigates this healthcare gold rush
Gold has long been revered as a health-giving metal. The ancient Egyptians, for example, believed it could cure all manner of physical and spiritual ailments (and Cleopatra is thought to have slept in mask of pure gold to enhance her youthful looks). The Romans used gold preparations to treat skin lesions and sores, and in the 1890s German bacteriologist Robert Koch discovered that gold compounds could curb the growth of a bacteria strain that caused tuberculosis.
Nowadays, the healthcare industry is taking medicinal gold to the next level with treatments and technologies that are not only saving lives, but that are bringing new understanding to some of the most challenging diseases faced by modern medicine.
“When we talk about gold in medicine, we’re talking about absolutely miniscule quantities,” says Trevor Keel, consultant head of technology at the World Gold Council. “The amounts in each treatment are so small you can barely imagine them, but the impact they have on human life is enormous.”
The key ingredient
Malaria is just one area where gold is making a significant difference. The (treatable) disease leads to an estimated 429,000 deaths each year, but incidences are decreasing thanks to early diagnosis, which can be carried out through rapid diagnostic tests (RDTs). These RDTs contain gold particles tens of thousands of times smaller than the width of a human hair, which produce a colour change indicating whether there’s malaria present in a patient’s blood sample. As the name suggests, they work quickly, in around 15 minutes.
“In 2016 some 300 million malaria RDTs were manufactured and distributed,” says Keel. “Without the gold component, the test wouldn’t work, so it’s having a direct and significant impact on global health.”
Since gold is nonreactive to chemicals and other fluids, it’s ideal for other diagnostic applications, too. Doctors can make it safely radioactive, then suspend it in a colloidal solution that is injected or swallowed and then tracked as it moves through the body. It sounds like the stuff of science fiction, but this treatment is integral in identifying internal blockages and even some types of diseased tissue and tumours.
But while it’s doing vital work in healthcare diagnostics, it’s gold’s role in active treatment that’s particularly exciting for the medical industry. The first gold nanoparticles were created by influential scientist Michael Faraday, back in 1857. Using more advanced forms of his discovery, researchers are now getting closer to finding solutions for problems once considered insurmountable.
Chemotherapy, for example, is an effective treatment for cancer but it’s also indiscriminate, targeting healthy and cancerous cells alike and causing unpleasant and distressing side effects in the process. Extensive bodies of research, however, show that gold particles could be used as an efficient delivery system for cancer drugs, targeting areas of disease with minimal side effects. For a while this was largely theoretical research, but earlier this year a team from the National Cancer Institute in the US proved its effectiveness on mice, and is now pushing for human trials.
Also this year, scientists in China used tiny gold photoreceptors to restore vision to blind mice. It’s still early days for the technology, but the researchers say they’re confident their findings could be used to help treat humans with macular degeneration and other forms of blindness.
Keel also adds that gold is playing a “hugely important” role in antibiotic resistance, which is a huge threat to global health. Scientists in Switzerland, for example, have used gold nanoparticles to create a new generation of broad-spectrum antiviral drugs. When these drugs are injected into the body, the particles mimic human cells and ‘trick’ a virus into binding with them. When this happens, resulting pressure from the action renders the virus completely harmless. In theory, such drugs could one day act as a ‘cure-all’ for currently hard-to-treat diseases.
However, as Keel says, despite the groundswell of research it could take a while before such treatments become commercially viable – although he’s certain that they will. “A lot of these new uses for gold are still under development, and while some of them are in clinical trials, it can be a long and costly process bringing them to market.”
But he points to one specific drug as an important precedent for industry approval. “Auranofin contains gold, and was developed in the 1970s for the treatment of rheumatoid arthritis. It was eventually superseded by more effective arthritis treatments, but because it has already been approved by the FDA [the US food & drug association], a lot of pharmaceutical companies are revisiting it for other applications.” Indeed, researchers have already seen very promising results with Auranofin in the treatment and detection of HIV and AIDS-like viruses.
In 2017, there were more than 33,000 citations of the gold particle nanotechnology in academic medical journals, compared to around 9,000 just a decade previously. Given gold’s increasing prominence in the healthcare industry, it’s no surprise that analysts forecast the global gold nanoparticles market will grow at a compound annual growth rate of 18.84% until 2021. But will that have a direct impact on the gold market itself?
“Not directly, no,” says Keel. “The quantities being used in medical trials and in existing treatments are, and will always be, tiny. In 2017 around 333 tonnes of gold was used in technical applications around the world, mainly by the electronics industry. And consider that every single mobile phone in the world contains around a dollar’s worth of gold. Medical applications don’t come anywhere close to making a dent in these figures, so I can’t imagine a time when healthcare demands will ever rival or encroach on demand for gold from other industries.”
But, he says, this is a positive thing. For a start, such are the microscopic quantities of gold being used in the healthcare industry, breakthrough treatments – when they arrive – will never be at risk of running out. Small quantities also incur small costs, so the star ingredient, gold, will never be prohibitively expensive for research labs. And, as new developments come to the fore, people’s perception of gold will evolve. “So many people assume gold’s main purpose is for jewellery or investment,” says Keel. “So broadening their understanding of it, and its many valuable applications is amazing.”
And what’s a more valuable application than saving lives?
Rachel England is a UK based journalist who has worked with numerous titles including The Independent and The Times