Zinc oxide is the metal zinc that has been oxidized. The chemical formula is ZnO, 1 zinc atom and 1 oxygen atom held together by an ionic bond. Zinc oxide does occur in nature as the mineral zincite, but it is quite rare and commercially unavailable.
I have done a few stool samples in my time and have always just stored them in the fridge, until the next day to take them into the docs. Good luck hun I hope they get it sorted.
The shelf life of the DNA testing kit is four years. This means that even if you are unable to use the kit right away, the unopened kit can be used up to four years from the date that you first received it. Once the DNA sample is collected, the samples are good for at least three months at room temperature.