Best stuff to preserve specimen

[Tennyson]

So at school, my science teachers have never seen a bristle worm, so I said I could bring one in if I catch it. I haven't caught any of them yet becuase I can't find them, but when I do they said I should preserve it in something.

Whats the best thing I could do to preserve the specimen without harming the body that much?

Thanks!

 

[psychofishy]

i read somewhere that vodka would work ?

 

[Tennyson]

I wikipedia's vodka, and it doesn't seem to have any preserving capabilities. Thanks though. I know its an alchohol that preserves stuff, but not which kind is best.

 

[Myrddraal]

How long are you wanting to preserve the worm? Rubbing alcohol will work for a while.

 

[LeslieH]

For soft bodied animals a solution of 5% formalin (diluted formaldehyde) is best. It might be available at a local pharmacy. It needs to be handled carefully - use gloves & have good ventilation in the area. 70% ethyl alcohol is a reasonable substitute although the fixation won't be as good. Rubbing alcohol, vodka, white rum, can all be used as long as they are over 70% (= 150 proof) or higher.

 

[Tennyson]

I think I'll try rubbing alcohol since I won't have it very long. Thanks!

 

[plateboy3293]

Why do you want to kill a bristle worm?

 

[Tennyson]

My biology teachers would like to see a specimen and so do my friends, so I figured I could capture one and show them. Plus I find them unapealling and they creep me out.

By the way, I caught one!!! I'm so happy, its around 4 inches long and can stretch out around 7 or 8 inches. It took 45 minutes of louring it out with silversides juice, but I caught one, the only thing there are atleast 3 more in my tank. Oh well.

How long will rubbing alcohol last? I have spring break now for around two weeks so I don't want to use it so soon if it won't preserve it well.

thanks!

 

[mamagoose45]

Just a side note so you make sure you don't get in trouble - if for any reason you do use vodka or rum, I would make sure to clear it with your science teacher and principle so that there is no confusion regarding you bringing alcohol onto the school properties. Sadly, that's the type of thing that would be totally innocent but could get you expelled. Just watch your butt!

 

[Tennyson]

Yeah, I'm clearing it with my biology teacher by email. Thanks for the warning though.

 

[LeslieH]

Hi Tennyson -- You have fixation and preservation confused. Formaldehyde/formalin bonds with the proteins in the body - that's called fixation. It produces the best specimens. Alcohol does not bond. A high proof/percent alcohol is sterile and prevents the usual agents of decay like bacteria and mold from attacking the body, thereby preserving it. Specimens in alcohol are softer and more likely to be distorted but they will last for years. Formalin was first used in the 1920s I believe. There are specimens in museums which were originally preserved in alcohol 200 years ago and are still usable.

 

[Tennyson]

You said earlier that formalin should be handled carefully and in a well ventalated area. So is it potentially dangerous to us? I don't really understand, is formalin the same as rubbing alcohol or something else? Is it better? I just want to preserve the thing for maybe a month or two, it would be great if rubbing alcohol lasted longer though.

 

[LeslieH]

Formalin is formaldehyde that's been diluted. Formaldehyde is embalming fluid used by morticians to prepare bodies for burial and to prepare lab specimens for study. In small but continuous doses over time it can be carcinogenic. If a person were careless & breathe strong fumes it could do damage to the respiratory tract; get it in the eyes or nose, on mucus membranes, or a cut it will hurt & may cause damage, and it's poisonous when swallowed. Like many chemicals its usefulness outweighs the potential for harm and it is commonly used not only in science but also in manufacturing. For example, it is used in the textile industry and also in the lumber industry. I always use gloves & have good ventilation when I work with it.

Formalin and all types of alcohol are different things. For your purpose the rubbing alcohol will do just fine. Any type of alcohol will keep the animal well preserved for years as long as it's above 70% alcohol.

 

[Tennyson]

Wow, you really know your stuff. Thanks for the help.