Electrospray ionization Fourier transform ion cyclotron resonance at 9.4 T.
We present the first results from a new electrospray ionization Fourier transform ion cyclotron resonance mass spectrometer operated at a magnetic field of 9.4 T (i.e. > or = 2.4 T higher than for any prior FTICR instrument). The 9.4 T instrument provides substantially improved performance for large molecules (> or = 50% increase in mass resolving power) and complex mixtures (> or = 100% increase in dynamic range) compared to lower-field (< or = 6 T) instruments. The higher magnetic field makes possible larger trapped-ion population without introduction of significant space--charge effects such as spectral peak shift and/or distortion, and coalescence of closely-spaced resonances. For bovine ubiquitin (8.6 kDa) we observe accurate relative isotopic abundances at a signal-to-noise ratio greater than 1000:1, whereas a complete nozzle-skimmer dissociation electrospray ionization (ESI) FTICR mass spectrum of bovine carbonic anhydrase (29 kDa) is achieved from a single scan with a signal-to-noise ratio of more than 250:1. Finally, we are able to obtain mass resolving power, m/delta m > 200,000, routinely for porcine serum albumin (67 kDa). The present performance guides further modifications of the instrument, which should lead to significant further improvements.
Senko
M W
MW
Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, Florida State University, Tallahassee 32310, USA.
Hendrickson
C L
CL
Pasa-Tolić
L
L
Marto
J A
JA
White
F M
FM
Guan
S
S
Marshall
A G
AG
D000818:Animals; D002256:Carbonic Anhydrases / Q000737:chemistry; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D017357:Cyclotrons; D004574:Electromagnetic Fields; D005583:Fourier Analysis; D013058:Mass Spectrometry / Q000295:instrumentation*; D012709:Serum Albumin / Q000737:chemistry; D014452:Ubiquitins / Q000737:chemistry
D012709:Serum Albumin; D014452:Ubiquitins; D002256:Carbonic Anhydrases