A NEW computational trick developed by researchers at the University of Warwick, UK, is said to double the resolution, sensitivity, and mass accuracy of Fourier Transform Mass Spectrometry (FTMS) with no cost penalty.
The new approach hinges around the phasing issue that allows plotting of spectra in absorption mod, and can be used in all FTMS including FT-ICR, Orbitrap, and FT-Tof instruments. The researchers, led by Professor Peter O’Connor, say it will have applications in many fields, including proteomics, metabolomics, and pharmaceutical analysis.
In their abstract, the Warwick team – O’Connor plus Yulin Qi, Mark Barrow, and Huilin Li – note that the Fourier transform spectrum can be presented in three modes. Absorption mode is commonly used in FT-NMR, magnitude mode in FT-ICR, and power mode in engineering applications.
In FT-NMR, it is understood that absorption mode gives a narrower peak shape and therefore a more useful spectrum.
The researchers report that their new approach to the phase equation allows broadband phase correction, which in turn makes it possible to routinely apply absorption mode in FT-ICR.
Their empirical data confirms that, in addition to resolving power improvements over magnitude mode, this approach also improves the signal-to-noise ratio (S/N) of a spectrum by a factor of 1.4, and can double the mass accuracy, with no extra cost in instrumentation.
The method is detailed in the journal Analytical Chemistry, in a paper entitled Absorption-Mode: The Next Generation of Fourier Transform Mass Spectra. Full access is restricted to subscribers, although the abstract can be viewed here.