please help me on GC Method Development

[junagadh1]

Hello All

I am trying to develope my GC method on protein samples

I use tri-sil reagent to derivatize my sample and use sodium sulfate to remove my water into sample and use pyridine to extract my Bis-Tris from sample'

some how i can not remove my water in sample

Could anyone help me out how i can remove my water form sample?

Thanks in advance for your hepl

[chromatographer1]

Is your pyridine anhydrous?

If you think the answer is yes, then did you freshly distill it ?

If the answer is no then the first question's answer is also no. At least it is very likely.

Pyridine does not stay anhydrous for very long without special precautions.

Vacuum and heat will dry samples somewhat, but not usually completely.

best wishes,

Rod

[Consumer Products Guy]

We routinely dissolve consumer products containing up to 90% water by dissolving in DMF and mixing a portion with BSTFA. Then injecting directly. We've never even tried to remove BSTFA excess.

We might dry a sample first to concentrate; anything lost would be voltaile, and if voltaile already, might not need derivatization !!!

What exactly are you looking for in "protein samples" ? Proteins themselves are obviously too large to do by GC.