I am working with vitamin D3 and every time wea re facing problems with storage and lost activity of vitamin D3. We had tried every possible method such as working in low light, storing at -80-degree c, single use aliquots. And i am not able to use the vitamin D3 or, calcitriol after one month. it's not always possible to buy a new vial every time. Few people suggested us to purge the solutions with some inert gas.

Can you suggest me how to purge argon in the vitamin d3 solution as we don't have glovebox facility in our department, and we also store the vitamin D3 as 5ul aliquots in Microcentrifuge tube. We can't buy huge amount of vitamin D3 because it's pretty expensive and come as a 1mg vials. Can you suggest me any solution to purge argon in those MCTs. As someone mentioned to spray argon, and I could not understand the same.