Medical uses
From its early historical use in ancient cultures, gold is becoming increasingly important in many modern medical treatments, ranging from drugs to precision implants.
Gold has been used for many years to successfully treat rheumatoid arthritis. The Frenchman Jacques Forestier reported in 1929 that the use of gold complexes was beneficial in the treatment of arthritis. Later work after the Second World War demonstrated conclusively that gold drugs are effective in treating rheumatoid arthritis patients. Many experts consider gold to be among the most effective drugs for reducing the inflammation in the joints and so reducing the symptoms of pain and stiffness
Since it is "biocompatible", gold plays an important role in medical implants. Gold also possesses a high degree of resistance to bacterial colonisation and because of this it is the material of choice for implants that are at risk of infection, such as the inner ear. Gold has a long tradition of use in this application and is considered a very valuable metal in microsurgery of the ear.
Gold is also used in the treatment of prostate cancer. Using small gains of gold (about the size of a grain of rice), doctors can accurately identify the position of the patient’s prostate during treatment. The improved accuracy allows for a more precise radiation dose and a more targeted area for the treatment of the tumour. Other medical implants that contain gold are pace makers and insulin pumps. Gold is used in these devices because of its high level of reliability for the internal electronics.
Some new medical technologies rely on the ability of tiny gold nanoparticles to specifically collect in a cancerous tumour by passing through the inherently leaky blood vessels attached to a tumour. So, when injected into a patient, there is a means by which a potent anti-cancer compound attached to a gold nanoparticle, can be directly and accurately delivered to a tumour whilst avoiding healthy body tissue. Such an effective drug delivery mechanism with reduced toxicity is considered to be a major step-forward. Why use gold as the delivery mechanism? Well gold has a major advantage in being a very biocompatible metal.
In 2000, a US-based company CytImmune showed that gold nanoparticles could bind anti-cancer compounds onto their surface and carry these drugs safely through the blood stream, delivering them to tumours. The first first-in-man Phase I clinical trial of CytImmune’s gold-based drug began in 2006. This on-going trial will evaluate the safety of the drug and its tumour shrinking response.
