By dingyuanma on Thursday, December 25, 2003 - 10:02 pm:
I learned that nonporous reversed-phase column with smaller particles(1.5um) have some advantages,such as higher recovery for protein analysis.We have a Mariner ESI-TOF and a common HP1100 HPLC systerm, I don't know if this column can work well in our instrument. I know that TFA may cause some supression,but I don't know if it can destory the instrument equiped needle tip in our ionspray sourse.I would appreciate it very much if someone could give me some advise.
By Anonymous on Friday, December 26, 2003 - 03:14 am:
In principle no need to use TFA. Use formic, is as good. Works with porous, but do not know on nonporous.
By dingyuan on Sunday, December 28, 2003 - 08:29 pm:
Thank you for your concern.I think porous is avaliable for peptide analysis rather than protein.Would you please give me more concrete information.
By MG on Monday, December 29, 2003 - 06:48 am:
I've used TFA in mobile phases periodically at concentrations less than or equal to 0.2% (v/v) with LC/MS. To my knowledge, it never damaged my ion source. However, it will cause ion suppression, and will stay around as background even when you think you have flushed your system adequately.
By dingyuan on Tuesday, December 30, 2003 - 12:33 am:
Thanks.We have destroy our tip using chloroform as solvent and think halogen may have bad effect.
That prevent me from drawing a rapid decision.
By MG on Tuesday, December 30, 2003 - 06:06 am:
Is your ESI needle stainless steel? I would be surpised if chloroform caused damage, although you might not get much ionization.
By dingyuan on Thursday, January 1, 2004 - 02:39 am:
Yeah, a stainless steel tip is destroyed when using chloroform as solvent. I think halogen may cause some problem.
By Uwe Neue on Thursday, January 1, 2004 - 07:50 pm:
Symmetry C18 columns work very well with peptides and proteins with formic acid as the modifier. They are available in a 10 nm variety for peptides and a 30 nm variety for proteins. Recovery is without difficulty.
By dingyuan on Friday, January 2, 2004 - 07:06 pm:
Is sysmmetry C18 a waters product? I obtained some information about Vydac, Jupiter, BioBasic, Discovery BIO Wide Pore.I hope someone could kindly give me some advise.
By Basil on Wednesday, January 7, 2004 - 04:26 am:
Yes dingyuan, Symmetry is a Waters product..
I've been working with a Symmetry C8 for a developing new methods and now I'm going to buy a C-18 for an specific one.
Hope it helps
Basil
By dingyuan on Saturday, January 10, 2004 - 01:09 am:
I went away some days. I am pleased to recieved your recomments.Thanks.
By Anonymous on Wednesday, June 9, 2004 - 11:02 am: