Dear all,

I am wondering if anyone has the experience working on GCNCIMS. Recently I have done the derivatization on drug using TFAA prior to GCNCIMS. In brief, I added 20uL TFAA into the drug in the presence of 100 uL dry acetone and the mixture was heated to 50 oC for 30 minutes. Afterward, I added 0.5 mL iso-octane and 0.5 mL water and vortexed for 30 sec to destroy excessive TFAA and extracted the corresponding TFA acid. After that, the iso-octane layer was injected into the GC-NCIMS system. However, I found a huge background in the chromatogram. Did I do something wrong? Please advise.

aaa