By Gina Evangelidis, MMTA
The technique founded by Gunther Von Hagens in 1978, allows biological specimens to be prepared for research, teaching and demonstration purposes.
My most recent encounter with plastination took place at New Scientist Live where the Royal Veterinary College were exhibiting some of the specimens used by their students. These piqued my interest as did the silicone standard plastination process.
There are five steps to this process: fixing, dehydration, forced impregnation, positioning and curing.
Fixing, or embalming as we may more commonly know it, prevents the specimen from decaying and is the backbone of all the work that follows. This prepares the specimin to be placed in a bath of either acetone or alcohol at temperatures between -15 ° C to 25 ° C. At this temperature, the fat and bodily fluids are removed from the specimen, preparing it for impregnation.
Impregnation takes place by placing the specimen in bath of silicone and vaporising the acetone. By now, the specimen can be positioned as desired and cured to harden. This final process ensures that it is able to be used in future without the requirement for special storage or handling procedures—particularly useful for educational establishments and students.
The key benefit of plastination is that it gives a real, tangible understanding of the anatomy, and thus enriches and enhances students’ studies. Of course, this is not the only way it is used – macabre artistic sculptures are created through the use of plastination, and whilst somewhat uncomfortable, the use of this process in modern day teaching and medicine far outweighs this.
Silicon or Silicone?
- Silicon is a naturally occurring chemical element, whereas silicone is a synthetic substance.
- Silicon is the 14th element on the periodic table. It’s a metalloid, meaning it has properties of both metals and non-metals, and is the second most abundant element in the Earth’s crust, after oxygen.
- Silicon readily bonds with oxygen and is rarely found in nature in its pure form. When silicon and oxygen mix with reactive metals, the result is a class of minerals called silicates, which includes granite, feldspar and mica.
- Elemental silicon is a major player in modern electronics because it’s an ideal semiconductor of electricity. When heated into a molten state, silicon can be formed into semi-conductive wafers, to serve as the base for integrated circuits.
- Silicone, by contrast, is a synthetic polymer made up of silicon, oxygen and other elements, most typically carbon and hydrogen.
- Silicone is generally a liquid or a flexible, rubberlike plastic, and has a number of useful properties, such as low toxicity and high heat resistance. It also provides good electrical insulation.
- In the medical field, silicone can be found in implants, catheters, contact lenses, bandages and a variety of other things, including personal care items, such as shampoos, shaving cream and sex toys.
- Due to its high heat resistance, silicone makes up a lot of kitchenware, such as oven mitts, tongs and pan handles; silicone’s non-stick properties also make it useful for cookware coatings. Additionally, the material’s heat resistance and slipperiness make it an ideal lubricant for automotive parts.
- And, like silicon, silicone is important in electronics — it’s used to make casings that can shield sensitive devices from electrical shocks and other hazards.
Source: Joseph Castro, @livescience
