I have been trying to figure out a method for preparing individual doses of research chemicals which can be stored for the long term. One possible method is the blotter approach. Another method that I am considering is the use of capsules. One problem with capsules is that even the smallest size is much larger than is needed for doses such as 10 mg. As a result, along with the research chemical, the capsule will contain air with oxygen and a degree of humidity (given the practicalities of the environment in which this will take place). Since both oxygen and humidity contribute to the decay of research chemicals this is a potential problem for long-term storage. One possible solution to this problem would be to replace the air in the capsule with a solid. In other words, after placing the desired amount of the research chemical in the capsule, the capsule would be topped off with another solid/powder. It would be important that the solid be nonreactive with the research chemical and not be toxic/harmful/disruptive to the human body. I would appreciate suggestions as to the ideal solid/powder for this purpose (or other suggestions to deal with preparing individual doses for long-term storage). The intent is for the capsules to be stored in sealed glass containers with desiccant and oxygen absorbers, and placed in a freezer.