Iodine is the active ingredient in IKI. It is present in this solution in its aqueous form, which is used in experiments. However, it is also present in tiny amounts in its gaseous form. This gas may slowly leak from any container it is kept in, staining the items around it brown or purple. If the packaging near your IKI solution has been dyed brown but the solution is still in its container, it should work normally in your experiments.