Hello. I'm currently working with a Bruker UHPLC-qTOF instrument and until now we've been using sodium formate for internal and external calibration in positive mode analysis, but I often have to erase calibration points to ensure the appropiate calibration error.
Is there any other compound or mix that I could use to improve mass error in my analysis? Or maybe am I doing something wrong when calibrating the instrument? Some of my results have a mass error such as 10 ppm or more, even when analyzing only standard solutions.
Thank yo very much.
You should contact your manufacturer's technical support. Usually, if not always, the best calibrant for a specific equipment is the one the manufacturer recommends. In my experience, a mass error as big as you describe is due to other reason than a wrong calibrant.
Thank you both. We're using on-the-fly calibration at the start of every chromatogram (before dead volume time), and I also calibrate externally in HPC mode before each set of samples. Both calibrations are done with sodium formate. I have no problem in negative mode, only in positive. Maybe there is something wrong with my positive mode method, so I'll check it better for next time. I'll also look into the posibility to use the tuning mix for weekly tuning.
Thank you very much.
- Badges
- Science topic
- Similar topics
- Instrumentation Engineering
- Instruments