Did you know that precious metals like gold are being used to enhance cancer treatments, medical testing and more? That’s right – gold’s uses span far beyond jewelry, coins and bars. In fact, it’s helping to improve and even save lives through cutting-edge medical technology.
From simple dental restorations like crowns and bridges to advanced cancer therapies and bioimaging, gold has proven to be a promising material for various medical applications.
Is Gold Still Used to Treat Arthritis?
Gold therapy was once a popular treatment for rheumatoid arthritis. It’s still available today, but less common due to its side effects and the presence of newer medications like disease-modifying anti-rheumatic drugs (DMARDS).
Gold therapy (also known as chrysotherapy) uses gold salts that are either injected into the muscle or taken orally. The gold salts have anti-inflammatory properties, which may stop the cells from creating histamines that attack the immune system. But beyond that, it’s still not fully understood why gold salts are effective for RA. Gold therapy was common from the 1930s until the late 80s, when more effective medications with fewer side effects took over.
Gold Nanoparticles: Tiny Size, Big Impact
Gold is most often used at the nanoscale in medicine, in the form of tiny nanoparticles (“nano” = one billionth of a meter). Gold nanoparticles (GNPs) typically range from 1 to 100 nanometers in diameter – thousands of times smaller than a strand of human hair. GNPs are often suspended in a liquid, and the solution is called colloidal gold. Colloidal gold has been around for centuries and is commonly used in research and diagnostics.
GNPs interact with light through a phenomenon called localized surface plasmon resonance (LSPR). Depending on their shape, size, and surrounding environment, the particles can absorb and scatter light differently. As a result, differently-sized nanoparticles emit different colors: smaller GNPs may appear red, while larger ones are blue or purple.
Advantages of GNPs
Gold nanomedicine is used in bioimaging, diagnostics, targeted drug delivery, photothermal therapy for cancer and more. GNPs are highly customizable and versatile. They can be made into different shapes like spheres, rods, cones, stars and more – and the shape influences how they interact with light and behave in the body.
Scientists can attach drugs, DNA, antibodies, peptides and other molecules to GNPs for targeted treatment. Gold is very biocompatible because it’s chemically inert – it doesn’t react with biological systems, making it relatively safe for use inside the body. (This is also why pure gold is technically edible!)
How Does Gold Help Diagnose Diseases?
Gold nanoparticles are used as contrast agents in x-rays and CT scans, acting like highlighters to help doctors visualize specific areas more clearly. Because gold is very dense, it blocks x-rays much more effectively than soft tissue, making it stand out in imaging. Gold nanoparticles can also be coated with molecules that help them bind to specific cells (like cancer cells). This targeting ability gives doctors more detailed images of tumors, blood vessels and organs, aiding in more accurate diagnoses.
Rapid Testing with Gold
GNPs are also super useful in rapid medical tests because they can bind to specific substances, triggering a visual color change. When suspended in a liquid, stable GNPs typically appear red. But when they encounter a target – such as a virus, protein, or hormone like hCG (used in pregnancy tests) – they can bind and clump together, a process called aggregation. This creates a shift in how the particles interact with light, changing the color from red to blue or purple. This technology is used in many rapid diagnostic tests, including those for pregnancy, COVID-19, malaria, HIV and more.
What Role Does Gold Play in Cancer Treatment?
Not only can gold nanoparticles help diagnose cancer through their use in bioimaging, but they’re also used in several types of treatment: photothermal therapy and targeted drug delivery.
Photothermal Therapy
Photothermal therapy is a category of cancer treatment in which gold nanoparticles are used to destroy cancer cells using heat. One of the methods, for example, involves laser activation:
- First, GNPs are injected into the body, where they eventually accumulate in tumor tissues – either passively through leaky tumor blood vessels or actively via targeting molecules on their surface
- Then, a laser emitting near-infrared light is applied to the tumor site
- The GNPs absorb the near-infrared light and convert it into localized heat
- This heat kills cancer cells within the tumor, while minimizing harm to the surrounding healthy tissue
Simply put, GNPs act like tiny heaters, selectively killing cancer cells!
Photothermal therapy offers a highly-targeted and minimally invasive approach to cancer treatment, often with fewer side effects than traditional chemotherapy or surgery. One real-world example of this is AuroLase Therapy, which uses gold-based nanoparticles to treat prostate cancer.
Targeted Drug Delivery
Different types of coatings for gold nanoparticles have been developed to selectively target specific cells – like cancer cells – for drug and vaccine delivery. This targeted approach is remarkable because it allows treatment to reach damaged cells with minimal harm to the surrounding healthy cells. And because gold is so chemically stable, drugs attached to GNPs are often less likely to degrade before reaching their target.
The Future of Gold Nanomedicine
It’s remarkable that a material as ancient and familiar as gold – a metal cherished since antiquity – is now at the forefront of modern medicine. GNPs are already showing exciting potential in areas like HIV treatment, blood diseases and gene editing. For example, GNPs are being explored as delivery systems for CRISPR technology, potentially offering a safer way to edit genes compared to current methods.
Maybe one day we’ll have tiny gold-coated robots cruising through our bloodstream, repairing things at the cellular level. Sounds like sci-fi, but who knows!
Other Precious Metals in Medicine
Gold isn’t the only precious metal that plays an important role in medicine: silver, platinum and palladium also offer impressive functionality and biocompatibility. Platinum, for example, is used for cancer treatments – plus various medical implants like pacemakers, stents, catheters and more. Palladium is also used in medical devices and implants, and it serves as a catalyst in the manufacturing of pharmaceuticals.
Last but not least, silver is used in surgical tools, needles, catheters and wound care due to its antimicrobial properties. In fact, Hippocrates wrote about using silver for wound care as early as 400 BC. Today, silver ions (positively charged atoms or molecules of silver) are used in dressings and wound treatments to combat harmful bacteria.
Every Bit Counts: Preserving Precious Metals
A major benefit of using precious metals like gold at the nanoscale is that you don’t need to use a lot of metal to make an impact. Precious metals are rare and finite, but luckily, they can be infinitely recycled.
Even small amounts of gold – like the amount in a single dental crown – are too valuable to waste. Recycling precious metals is essential. In 2024, recycled gold made up 28% of the global supply, helping to meet demand without further depleting natural resources. And as time goes on, responsible metal recovery will only become more and more critical.
Gold refineries like Garfield Refining specialize in recycling precious metals, ensuring that they’ll be refined and repurposed to create new products. If you or someone you know has unwanted precious metal items – whether it’s old jewelry, silverware, a dental crown, or something else – we can help you recycle for cash!
Interested in learning more about precious metals recycling? Check out our other posts like ‘What is Precious Metals Refining?’ or ‘What is Dental Scrap Refining?’
Do you have gold, silver, platinum or palladium that you’re looking to sell? Garfield has specialized in refining since 1892, providing top payouts and award-winning service. Download a free shipping label to send us your scrap today!