[bobs]

I have identify in cephlosporin C in our culture. I am not able to detect it below 0.5 ug/ml conc. I am using positive ion mode..is switing to negative ion mode will increase the senstivity?  Cephlosoprin is monoamino dicarboxylic acid...how i can increase the sentitivity of my mass spect..i am using shimadzu IT-TOF.

[enahs]

Playing with the ionization potential as well as other electronic setting in the MS can potentially greatly increase your signal.