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- Posts: 1
- Joined: Tue Sep 14, 2010 8:04 am
Hi there,
My routine work is based on detecting a compound in clinical samples with a generation of standard curve at the beginning of each run on a LC/MS/MS.
The two solvents that i use are: AceN:Isopropanol and 0.5% Formic acid in water. I use a hypercarb column.
Usually, I get a nice single peak for both 12C and 13C that elutes at the same time, but recently I've been getting inconsistent peaks especially in the 12C. My 13C peaks are fine and what it's supposed to be but I've been getting multiple peaks/broad peaks or peaks that elute slightly earlier than usual for 12C. It's difficult to integrate the area due to this problem.
It's showing up for both my standards and the clinical samples so it's not due to the samples itself.
My pressure reading has been slightly elevated than usual.
I tried making new solvents, new guard cartridge, tried an older column but it's still showing the same thing.
Please help!!!!!
My routine work is based on detecting a compound in clinical samples with a generation of standard curve at the beginning of each run on a LC/MS/MS.
The two solvents that i use are: AceN:Isopropanol and 0.5% Formic acid in water. I use a hypercarb column.
Usually, I get a nice single peak for both 12C and 13C that elutes at the same time, but recently I've been getting inconsistent peaks especially in the 12C. My 13C peaks are fine and what it's supposed to be but I've been getting multiple peaks/broad peaks or peaks that elute slightly earlier than usual for 12C. It's difficult to integrate the area due to this problem.
It's showing up for both my standards and the clinical samples so it's not due to the samples itself.
My pressure reading has been slightly elevated than usual.
I tried making new solvents, new guard cartridge, tried an older column but it's still showing the same thing.
Please help!!!!!
