How to store fatty acids stock in nitrogen environment - (May/27/2009 )
I'm going to make palmitic acid, palmitoleic acid, oleic acid, linolenic acid, and linolenic acid stock solutions in ethanol and the protocol says "aliquots stored in nitrogen environment at -86C"
1. How can you make "nitrogen environment"? Do I have to use liquid nitrogen?
2. Fatty acids are easily oxidized. Is it okay to dissolve the fatty acids powder in room temp? Are there special handling tips for making stock solutions?
Thank you for your help in advance!
To prevent the FAs being oxidised, you need to prepare and store in an oxygen-free environment. This is commonly achieved by flushing a container with nitrogen gas. Ask a chemistry department, they will have the necessary equipment.
We ususally stored (oxidizeable) fatty acids by gasing the tube with nitrogen (not liquid) and then closing the tube quickly and sealing it airtight.
This usually worked quite well judging from HPLC and colorimetric diene or MDA assays.
Be sure to have a container and buffers that do NOT contain redox metals though! Usually this means Chelex-ing your buffers.