There are other products that are designed for absorption/ filter media, so it should be able to hold the juice mix fairly well. You could also add a little extra vegetable glycerine to increase the moisture content. I would need to figure out how to accurately dose the mix to get the correct nicotine concentration... Shouldn't be too hard if the juice is accurately labeled.
Where can I buy the empty portion packaging? The ones used in the all white snus seems to be different than what is used for most portion snus; I really appreciate how soft the material is.