How do I tune and calibrate a TOF out to m/z 4000?

Question

I have been trying to calibrate beyond the m/z range of the standard Agilent tuning mix, which only goes out to approximately m/z 2700. I put in CsI, but I only see the Cs+ ion and none of the adducts. Any thoughts?

Thanks.

Agilent · Accepted Answer

The TOF calibration curve is linear out to 4000 m/z so the default calibration using m/z 2721.8948 should provide satisfactory results. I've never tried to calibrate an Agilent TOF with CsI but I suspect that the clusters might not stay intact through the ion optics pathway. You might try to lower the fragmentor voltage to start; the default settings may be de-clustering the CsI clusters.