Many years ago I found a lengthy review article that was a survey of how various enzymes were stored. It had conditions under which enzymes were frozen and perhaps lyophilized IIRC. Recently I went through my massive collection of photocopied articles but I could not find it. I seem to recall that there were two authors, but I do not remember the name of the journal. The article was probably written in the 1990s, but I could be off by a few years on either side. I have tried extensive searches using Pubmed and less extensive searches using Google Scholar, but they have not produced the article I have in mind. Does it ring any bells with anyone? Any suggestions for the best way to search for it?