We're preparing for an experiment in our classroom and my teaching partner and I are at different points in the unit. I am concerned that the experiment will be less successful because of the freshness of the eyes. How long can they eyes be stored in the fridge before they have to be dissected and is freezing them an option?
Formaldehyde is a preservative, and is used to prevent decay. As long as the tissue is completely perfused (and there shouldn't be any issues with eyes that I'm aware of) it can be kept essentially forever. Have fun!
you can keep the samples in 4 degrees. Sometimes, in certain tissues, formaldehyde preservation makes them brittle. Or sometimes it makes certain slimy tissues easy to dissect. Nonetheless, it wont damage the morphology. And if you are not interested in protein/RNA isolation, then you can store the tissue as long as you want.