Asymmetric Window Function for FTMS Quantification
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for accurately quantifying ion abundances in Fourier Transform Mass Spectrometry (FTMS) face challenges due to interference between adjacent peaks and space charge interactions, particularly when determining isotopic ratios, leading to inaccuracies in peak intensity measurements.
Innovation Solution
A method involving the use of an asymmetric window function to adjust time domain data, followed by Fourier transformation to generate an absorption mode mass spectrum, with phase correction and integration within peak ranges to accurately quantify ion species, and optionally applying a calibration function to correct peak intensities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional detection methods are used in FTMS, then the measurement process is simple, but quantitative accuracy deteriorates due to peak interference and space charge effects
Solution Approach 1:
The patent applies a calibration function before quantitative measurement to pre-correct for space charge effects and peak interference. By performing calibration measurements with known ion abundances and deriving correction factors in advance, the system eliminates the need for complex real-time corrections during actual measurements, thus improving quantitative accuracy without significantly increasing measurement complexity
Solution Approach 2:
The patent introduces a calibration function as an intermediary element that mediates between the raw spectral data and the final quantitative results. This calibration function acts as a correction layer that accounts for systematic errors from peak interference and space charge effects, allowing accurate quantification without directly modifying the detection process
2Measurement precision
If peak integration is performed in M-mode spectra, then the quantification process is straightforward, but accuracy deteriorates due to interference between adjacent peaks
Solution Approach 1:
The patent introduces a calibration function as an intermediary that corrects peak intensities for interference effects before quantification. This calibration layer accounts for peak overlap and space charge distortions, enabling accurate integration without requiring complex deconvolution methods or reducing the simplicity of the overall process
Solution Approach 2:
The patent transforms the spectral data by applying a calibration function that adjusts peak intensity parameters to account for interference effects. By changing the parameter space through calibration corrections, the system maintains the simplicity of peak integration while achieving accurate quantification despite adjacent peak interference
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach allows for precise quantification of ion abundances by minimizing interference and accounting for space charge effects, providing accurate relative values of ions even in the presence of overlapping peaks and isotopic fine structures.
Implementation Method 1
The time domain signal is converted to a frequency domain signal in the frequency domain, for example using standard DFT (discrete Fourier Transform) algorithms
Implementation Method 2
As ions oscillate in the trap they pass one or more electrodes (typically referred to as pick-up electrodes) generating pulses of (image) charges on them which are measured in the time domain
Data Source
AI summary
Disclosed is a method of quantification of one or more ion species, in a sample of ions, using a mass spectrometer, the method including the steps of:obtaining a time domain data set corresponding to a signal induced by motion of the ions in the mass spectrometer;adjusting the data set by applying an asymmetric window function thereto;generating an absorption mode mass spectrum in the frequency domain including the step of applying a Fourier transform to the adjusted data set;determining peak ranges for one or more peaks in the mass spectrum associated with the one or more ion species;integrating, for each determined peak range, the spectral data within the respective peak range to generate a respective peak intensity value; andquantifying each of the one or more ion species on the basis of the respective peak intensity values.