Storage of purified proteins

[Gene Holowachuk]

Can anyone suggest some guidelines for the storage of highly purified
recombinantly produced proteins. We have purified a couple of cytokines
produced in E. coli, about 1 mg/l. What are the best ways for short term
and long term storage - 50% glycerol, lyophilized, -70 oC, etc. We have
found loss of activity when stored at 4 oC for longer than 1 week. Any
suggestions will be appreciated.
Cheers :-))

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**  Gene Holowachuk                |  Voice: 607/547-3937                **
**  Research Institute             |  Fax  : 607/547-3061 (attn Gene H)  **
**  Mary Imogene Bassett Hospital  |  email: geneh at research.mibh.org     **
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