[LabTech]

I am preparing some small molecules for my collaborator to run assays on.  All the compounds I have synthesized so far have turned out to be oils, so in order to transfer them to vials prior to submission I dissolve them in ethyl acetate, transfer the solution to a vial, and rotovap off the ethyl acetate.  I leave it on the rotovap for awhile to dry, and then allow it to dry further under high vacuum.  I met with my collaborator yesterday and he asked if all my compounds were lyophilized.  I have been in working in organic chemistry labs for a few years, and I have never seen anyone lyophilize their samples prior to assaying, unless it is a peptide.  So I was wondering, would there be any benefit to lyophilizing my samples?  I have always assumed by allowing my compound to dry on the rotovap and under high vacuum would suffice for drying my samples.   

[Ist]

Hi,

Firt of all the crystallization would be better. I have tryed sometimes the lyophilization of not peptid type compounds and I got nice clean product but it was really air- and moisture sensitive. The crystals from same compound was more stable than the lyophilized material.

[Ist]

The rota it`s not good for lyophilization! You need higher vacuum!