531.2 Standards
Posted: Wed Nov 16, 2011 5:50 pm
I am new to running 531.2 for Carbamates. I have two issues that I am looking for help on.
1. I have been losing response. How long are carbamate standards stable for? How often are you making them up?
2. I have been having some retention time shifts. The first four analytes usually have nice baseline separation, but once in awhile they all elute really close together and the remaining analytes also have earlier retention times. I'm sure this is an HPLC issue, but I'm not sure of why it's happening. I equilibrate 3 minutes before each sample is injected.
I would appreciate help.
Thanks,
Liz
1. I have been losing response. How long are carbamate standards stable for? How often are you making them up?
2. I have been having some retention time shifts. The first four analytes usually have nice baseline separation, but once in awhile they all elute really close together and the remaining analytes also have earlier retention times. I'm sure this is an HPLC issue, but I'm not sure of why it's happening. I equilibrate 3 minutes before each sample is injected.
I would appreciate help.
Thanks,
Liz