Physical signal modulation of XXXX mass analyzers increases precision and decreases noise.

@entity1054 @entity4270
Recently, an increased emphasis has been placed on the ability to make mass measurements with high accuracy and precision. The motivation for this is that high-precision mass measurements, together with isotope intensity matching, permit confirmation of molecular formulas and de novo molecular formula prediction, both of which enhance the value of proteomics and metabolomics data. The confidence of mass-based conclusions also depends on reliable estimates of uncertainty. However, determining the precision of a particular measurement remains a complicated process. For signals which are well-resolved and of sufficient intensity, an often-overlooked factor for high precision is the mass sampling frequency (abscissa, /\x). We have analyzed the impact of /\x on the centroid calculation of peak position, and find that existing quality standards, such as 4 or 5 samples per peak, may not be sufficient to achieve high precision. Time-domain and m/z-domain sampling frequency on @entity1054 ( @entity1054 ) mass analyzers can be improved using a new method that we call @entity4270 ( @entity4270 ). @entity4270 allows very substantial improvements by decreasing /\x without requiring specialized hardware or digitizers. In addition to providing accuracy improvements, @entity4270 also dramatically improves signal-to-noise ratios by removing coherent noise. Software to perform @entity4270 data processing is available as part of the PySpecTools package.
