Some of the writers on LabOnTheCheap have recently moved to UC Santa Barbara, where the Chemistry department sells us dry ice like this:
That’s right, as 10 lb blocks. There aren’t any of those dry ice grinders, or any tools of any sort, around, so to get dry ice in a reasonable size, you’ve gotta come with a chisel and a hammer. Really.
If your using dry ice to ship materials, that’s the end of the story. But if you’ve been using dry ice to flash freeze a sample in lieu of liquid nitrogen, you may want to check out this April 2016 paper that offers an inexpensive alternative. The paper, written by Tony Ismalaj and Dan Sackett, details cooling down alternative materials in a -80 such as aquarium pebble gravel which can be bought at Petco for just 93 cents a pound. We’re adding this to the lists of suggestions in our old Technical Tuesday: The Costs of Cooling.