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.
I just take one of the cartons out but not sure if that's really the most economic option in the long run. I'm just so confused about how long formula can be kept after use and how long those cartons realistically can be open for. Cow & Gate says 24 hours in the fridge, whereas Aptamil says 2 hours in the fridge. Cow & Gate gave LO horrible diarrhoea so I want to stick with Aptamil.