The Shimadzu/Kratos Axima CFR MALDI-TOF mass spectrometer is used for high accuracy peptide mass determination. It is also used for Peptide Mass Fingerprinting of proteins. The instrument is a Reflector with Post Source Decay capabilities for limited peptide sequencing.
Resolution of the instrument is ~10,000 allowing monoisotopic resolution up to ~2000 m/z.
The Axima has a mass accuracy of ~20 ppm (0.002%) in the range of 100 – 2000 m/z in the reflector mode with decreasing accuracy (~200 ppm) above 2000 m/z.
Sensitivity is 50 fmol of Angiotensin II (signal/noise is ~3 in this range) although it is most useful above 100 fmol.
Post Source Decay can be used to determine short stretches of amino acid sequence information from selected peptides. This is a useful tool for helping to confirm protein identifications after in gel digestion.