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HELP! I have big trouble with ghost peak! - (Aug/03/2009 )

Hellow?

my name is kim jae wook and I have big trouble with my capillary column.
I prepared reverse pahse column for seperation of low molecules such as lipid, metabolite ect.
but, I have huge trouble.

I bought 5um100 °A Magic C18 particle from Michrom BioResources and make capillary column
with laser puller and bomb.
It was simple plan, make capillary column and seperated by gradient HPLC, and anaylzed by
mass spectrometer

without ghost peak, it is really good, but ghost peak is problem. It's signal intensity is 10times
higher than phoshpolipids, so sample,s singal is died!

washing with methanol, isopropanol, chloroform, cyclohexene for overnight is helpless-still huge
ghost peak. even there is isocratic or mild gradient

recently, organic solvent with low pH can wash ghost peak from column, but it is still problem.
with system of my lab, i have to make column for running every time.
but there is still ghost peak every new column.

paricle is stored in methanol and they were wash by vortexing with methanol and spin down-it's 10times

so

Please help me. ghost peak may come from reverse phase material and it is hard to wash by my knowledge
it's bothering me over year.

I need your help.








tired student from south korea

-kim jae wook-

kim jae wook on Aug 3 2009, 11:13 AM said:

Hellow?

my name is kim jae wook and I have big trouble with my capillary column.
I prepared reverse pahse column for seperation of low molecules such as lipid, metabolite ect.
but, I have huge trouble.

I bought 5um100 °A Magic C18 particle from Michrom BioResources and make capillary column
with laser puller and bomb.
It was simple plan, make capillary column and seperated by gradient HPLC, and anaylzed by
mass spectrometer

without ghost peak, it is really good, but ghost peak is problem. It's signal intensity is 10times
higher than phoshpolipids, so sample,s singal is died!

washing with methanol, isopropanol, chloroform, cyclohexene for overnight is helpless-still huge
ghost peak. even there is isocratic or mild gradient

recently, organic solvent with low pH can wash ghost peak from column, but it is still problem.
with system of my lab, i have to make column for running every time.
but there is still ghost peak every new column.

paricle is stored in methanol and they were wash by vortexing with methanol and spin down-it's 10times

so

Please help me. ghost peak may come from reverse phase material and it is hard to wash by my knowledge
it's bothering me over year.

I need your help.








tired student from south korea



Why dont u try changing the guard cartridge of HPLC? maybe some junk has got accumulated on it and keeps eluting out e'time u run ur sample

-DRN-