HEPES vs TRIS - Least Worst Option?

Hallo! Have you found out the results now? Is there a significant negative influence on LCMS system when the injection content consists of 50mM HEPES or 20mM Tris.

Sorry for the delayed response. 

I've found that either works fine. I typically try to keep injection volume low (0.2-1 uL for 1uM protein). 

I've mostly been using 50mM HEPES 150mM NaCl and get great deconvolution results, even with a 3 min short method. I run at roughly 384 well plate throughput and have not had any long term issues, though I'm pretty diligent about sending everything to waste that is not my protein peak. 

Tris is supposedly better for the system but I haven't found much of a difference. 

The NaCl isn't great but necessary in most cases. It will increase NaCl adduct formation but it's fine for less complicated, smaller proteins (homogenous ptms and <150kDa). 

Surprisingly, our source/nebulizers is usually almost spotless (just a bit of ion burn) after 1000s of samples. 

Sorry for the delayed response. 

I've found that either works fine. I typically try to keep injection volume low (0.2-1 uL for 1uM protein). 

I've mostly been using 50mM HEPES 150mM NaCl and get great deconvolution results, even with a 3 min short method. I run at roughly 384 well plate throughput and have not had any long term issues, though I'm pretty diligent about sending everything to waste that is not my protein peak. 

Tris is supposedly better for the system but I haven't found much of a difference. 

The NaCl isn't great but necessary in most cases. It will increase NaCl adduct formation but it's fine for less complicated, smaller proteins (homogenous ptms and <150kDa). 

Surprisingly, our source/nebulizers is usually almost spotless (just a bit of ion burn) after 1000s of samples.