Silver nitrate (AgNO3) has been used in medical applications throughout history. From ancient Greece to modern day, it has a diverse range of uses that surgeons, podiatrists, dentists and even vets take advantage of. So what are these medical applications?
What is Silver Nitrate?
Silver nitrate is an inorganic and caustic chemical compound that is made by dissolving silver in nitric acid. It appears as a white crystalline solid and is water soluble, non-hygroscopic, and can be corrosive if ingested.
While it is used in a variety of industries, its one downfall is its ability to turn the organs and skin a blue-grey, even black colour. This condition is called argyria, and while it is generally harmless it can be permanent if large amounts of silver nitrate are consumed.
If you would like to know more about how silver nitrate behaves, check out our previous blog post where we’ve covered its properties, production, other uses and hazards.
Silver Nitrate in History
Records show that silver nitrate as a medical treatment has been used as early as 4000 B.C.E. It was used extensively in places like Ancient Greece, Rome and Macedonia for its disinfectant and anti-bacterial properties.
In fact, according to Herodotus, no King of Persia would carry water in anything but a silver jar. This is because it was believed to keep the water pure. Even during the Napoleonic Wars, Russian soldiers lined their casks with silver in order to clean water from rivers before drinking it. In fact, this is still a common method used in maintaining potable water.
These antibacterial properties are why many royal families used silver cutlery, and this is where the phrase “born with a silver spoon in his mouth” came from.
Hippocrates, the Father of Medicine, used silver to promote wound healing and often taught how it could control different diseases. From 702 AD – 980 AD, silver was also widely used in the Middle East for blood purification, heart conditions and to treat halitosis.
Fast-forwarding to the 19th century, silver nitrate was used in the eyes of newborn babies in order to prevent them from catching gonorrhoea from the mother.
However, given the corrosive nature of silver nitrate, it should not be used on tissue that can’t regenerate, such as the eyes. With the rise of modern antibiotics in the 20th century, silver nitrate as a treatment in eyes was completely replaced.
Ancient alchemists also widely used lunar caustic to cauterise excess tissue, including warts, verrucae and granulation tissue. Lunar caustic was the name for silver nitrate sticks, which are still in use today.
Cauterisation is a technique used in medical applications where a part of the body is burnt in order to remove it or close it off. It is used to prevent bleeding, to remove a growth, and even to protect against infection.
Silver nitrate cautery involves a caustic stick – made from AgNO3 – that is used to apply topical cauterisation. This method is commonly used in a variety of medical applications, including:
- In clinics for the removal or warts, verrucae, skin tags, excess granulation tissue, and more
- In umbilical stumps to dry up tissue and allow for normal skin to grow over
- In noses to cauterise superficial blood vessels that cause nose bleeds
- In haemostasis in order to close off a blood vessel and stop bleeding
- In dentistry for the removal of aphthous ulcers
Caustic sticks contain silver as well potassium nitrate. When these dried nitrate salts are applied topically to a growth or wound, the tissue moisture or blood dissolves them. They then chemically burn the tissue, closing off the wound or removing any unwanted tissue.
Silver nitrate is well known for its antibacterial properties. It is widely used as a disinfectant, antiseptic and antimicrobial agent in the medical industry. However, how silver nitrate and other silver compounds behave like this still remains a grey area.
What we do know is that most silver compounds, as well as other heavy metals, are toxic to bacteria because they have an oligodynamic effect. This means that they are able to destroy harmful organisms, or render them harmless.
Silver is the most effective of all the metals when it comes to antibacterial properties. This is because it has the most action and least amount of toxicity to cells. This is partly because of the zombie effect the silver ion has on bacteria.
Silver nitrate is used for its antibacterial properties in many applications, including:
- Podiatry: silver nitrate is used to kill cells in nail beds
- Wound healing: silver nitrate deters microbial growth
- Water purification: silver has long been used to disinfect water and keep it potable
At ReAgent, we sell a variety of silver nitrate products in a vairety of different grades. We also offer great deals on bulk orders, and can get your order shipped within 24 hours. Shop online today, or contact us to speak with an expert member of staff.
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