Cryobiology Science Projects

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RachaelShort

Registered Senior Member
Hi my name's Rachael and I'm currently looking for a science project involving cryotechnics. I can afford to spend a bit of money on this project as i can apply for CSIRO crest award funding that could be about $500. Other than that i have access to average high school science facilities - nothing too fancy.Thanks so so so much.
Rachael.
 
What are you looking to freeze? It's pretty routine to freeze cells in DMSO and thaw them as needed.
 
Well... I have more information now. I want to freeze a goldfish and bring it back to life (yes people, it IS possible) but now i need something that can be my aim (aka what i'm testing) so far i have one idea but i don't think it's very good, testing the theory that fish can survive in glaciers and completely frozen ponds. However, since liquid nitrogen does not mimic a glacier for time it takes to freeze the fish or the length of time the fish is frozen for and there aren't many goldfish swimming around Antarctica I don't think it is a good aim. I sort of have my heart set on liquid nitrogen so an aim that could incorporate that and be capable of winning a state science fair (year 9 & 10) would be so awesome. Thanks guys :):)
 
Some fish can be froze, I'm not sure if goldfish are one of them. Be mindful you will NEED to fill out an animal ethics application with your institution BEFORE you begin freezing fish. I know this seems shocking, but, you actually can't just start killing animals for experimentation willy nilly - you need some snotty knowitalls to OK said killing first :)
 
I know. I'm trying to prove the ethicalities at the minute. I just need an aim. And yes you CAN freeze goldfish. All i want is an aim.
 
The aim must line up with your course. It's therefor important you write your course outline first such that ONLY freezing a live fish can meet the stated educational aims.
 
RachaelShort said:
I know. I'm trying to prove the ethicalities at the minute. I just need an aim. And yes you CAN freeze goldfish.
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Can you provide a reference for that? I find it hard to believe you can freeze a fish in liquid nitrogen then thaw it without killing it.

I don’t think it’s a good idea to perform animal experiments, especially ones that likely result in death, for a high school biology project. No high school will have an appropriate animal ethics committee that can comment on such experiments.

If you really want/must use liquid nitrogen in your project, I suggest you concentrate on freezing/thawing enzymes then determining if they retain their catalytic function. Mind you, reagents such as enzymes and the chemicals needed to test their activity cost money. You will definitely need at least that $500 you mentioned.
 
I wouldn't muck about with liquid nitrogen. I've used loads of this stuff at work, and it's dangerous if you don't know exactly what you're doing. Besides, you can use dry ice as a safer stand-in for many simple demonstrations as it freezes at about -23 deg. It still makes an impressive amount of vapour without the risk of freezing a finger off!
 
I don't really understand WHY fish need to be frozen myself. What's the point of the experiment? There's NO WAY you could freeze a fish -190 and it's going to live, at least not without some hightech equipment. Some fish, I think, can live a few hours in -20. But, again, why do it? Just to show that it's possible? I don't think that's good enough for ethics approval.
 
Michael said:
There's NO WAY you could freeze a fish -190 and it's going to live, at least not without some hightech equipment.
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Actually you can. Many cold-blooded animals have natural antifreeze that prevents large crystals of ice from forming and rupturing cell membranes; there are pretty clear evolutionary advantages to an aquatic animal that can survive freezing ponds. As long as you get them cold quickly and warm them up quickly they will often survive the experience. (There are plenty of videos on Youtube showing this if you're interested.)
 
You know, I took a look. I wonder if the fish are frozen solid in the few seconds they are in liquid N2. I don't think so - I think they are somewhat frozen, but, I'm not convinced they are frozen solid. That said, liquid N2 is f*cking cold. So, maybe. I wonder if it were left their for, say, a day, it might change the structure of ice inside the cells and die?

A story about N2. My mate thought he was clever when he poured some N2 into a 7-11 big gulp coke to get it cold again - it got slushy and so he drank it. Then he start burping N2 as the dissolved N2 forced itself out of his mouth! He was actually a little scared, but, ended up OK :) What an idiot. Another time he poured a bit of N2 onto his friend head in the lab, it froze his hair, which broke off when he touched his head yelling WTF! Lastly, he tossed some N2 onto his grandmother one day... pfffff, she was OK, but freaked out nonetheless! I was thinking, shit, you could have given her a heart attack!
 
Thanks a lot for all of the replies they were really helpful i'm liking the enzyme idea. That was what i was looking for, an aim - something to test. So thank you very much. And for goodness sake people you CAN do it :):) So please please help me find aims
 
On second thoughts, dealing with enzymes might become both expensive and tricky. I have had another thought. You could do an experiment using yeast. Baker’s yeast (Saccharomyces cerevisiae) is readily available from supermarkets as it’s used by home bakers and beer brewers. And it’s cheap.

If you Google with phrases like “yeast experiments”, “yeast school lab”, “yeast metabolism” etc. you will find a heap of high-school level experiments you can do with yeast.

So, maybe you could design a project around freeze/thawing yeast and then testing its ability to metabolise (either aerobically or anaerobically, or both) various different types of sugars: sucrose (table sugar), glucose, fructose (fruit sugar) etc. The benefit of this type of experiment is that the readout of metabolism is easy – simply measure the amount of gas given off by the yeast solution. You could compare freezing in LN2 and at -20oC in an ordinary freezer. You could compare the effects of LN2 freezing with and without a cryopreservant (eg 10% DMSO).

The downside might be that there are no changes in cells’ ability to metabolise sugars before and after LN2 freezing as yeast is an extremely hardy organism.
 
any luck?

I've been following this thread as we are looking to do the same experiment for a science fair project. Have you had any luck thus far? Also, I am curious if any one knows what temperatures are the range that a goldfish would be able to survive with flash freezing in Liquid Nitrogen or dry ice.

BTW, the videos are on YouTube.
 
deLisscious said:
Also, I am curious if any one knows what temperatures are the range that a goldfish would be able to survive with flash freezing in Liquid Nitrogen or dry ice.

BTW, the videos are on YouTube.
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I’ve watched several of the LN2 freeze/thaw goldfish videos on YouTube, and they are far from convincing. Typically the fish is immersed in LN2 for only a few seconds which may not be sufficient for complete freezing.

But regardless of complete or incomplete freezing, in all the videos the ‘recovery’ of the fish is filmed for no more than several seconds. Yes, the fish start to move and swim around a little, but this is hardly evidence that a fish can survive the LN2 freeze/thaw process. I can all but guarantee you that those fish died several minutes later from the considerable internal cellular and tissue damage that would have occurred.
 
Unfortunately (for the assignment) the ethics committee will not allow me to work with fish. Their absolute limit is insects. I then argued that they were playing God deciding which animals deserved to live or die ect. ect. but I just got shouted at for that. So unfortunately I can no longer freeze a goldfish. So any ideas at all now would be very helpful. i would still love to work with cryotechnics though...
 
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