Grouping Amplitudes of TOF Extractions to Detect Convolution Due to Resolution Saturation

A method for grouping and combining amplitudes for a selected ion mass-to-charge ratio (m/z) from time-of-flight (TOF) sub-spectra in order to detect convolution, comprising:

• ionizing sample molecules producing a beam of ions using an ion source;
• performing a plurality of ion extractions on the beam of ions using a TOF mass spectrometer that includes a detector;
• receiving electrical detections from the detector for the plurality of ion extractions and, during each extraction, measuring the amplitudes of the ions hitting the detector over time using an analog-to-digital converter (ADC), producing a mass sub-spectrum for each extraction of the plurality of ion extractions;
• receiving the plurality of mass sub-spectra using a processor;
• selecting an ion m/z from the plurality of mass sub-spectra using the processor;
• for each mass sub-spectrum of the plurality of mass sub-spectra, assigning the amplitude and m/z of an ion within a m/z tolerance of the ion m/z to the corresponding amplitude band of a plurality of predetermined amplitude bands using the processor, producing a plurality of amplitude and m/z values for the each amplitude band;
• and
• for each amplitude band of the plurality of predetermined amplitude bands, combining the plurality of amplitude and m/z values into a peak using the processor, resulting in a plurality of peaks corresponding to the plurality of predetermined amplitude bands.

A computer program product, comprising a non-transitory and tangible computer-readable storage medium whose contents include a program with instructions being executed on a processor so as to perform a method for grouping and combining amplitudes for a selected ion mass-to-charge ratio (m/z) from time-of-flight (TOF) sub-spectra in order to detect convolution, the method comprising:

• providing a system, wherein the system comprises one or more distinct software modules, and wherein the distinct software modules comprise a control module and an analysis module;
• instructing an ion source to ionize sample molecules producing a beam of ions using the control module;
• instructing a TOF mass spectrometer that includes a detector to perform a plurality of ion extractions on the beam of ions using the control module;
• instructing an analog-to-digital converter (ADC) to receive electrical detections from the detector for the plurality of ion extractions and, during each extraction, measure the amplitudes of the ions hitting the detector over time using the control module, producing a mass sub-spectrum for each extraction of the plurality of ion extractions;
• receiving the plurality of mass sub-spectra using the analysis module;
• selecting an ion m/z from the plurality of mass sub-spectra using the analysis module;
• for each mass sub-spectrum of the plurality of mass sub-spectra, assigning the amplitude and m/z of an ion within a m/z tolerance of the ion m/z to the corresponding amplitude band of a plurality of predetermined amplitude bands using the analysis module, producing a plurality of amplitude and m/z values for the each amplitude band;
• and
• for each amplitude band of the plurality of predetermined amplitude bands, combining the plurality of amplitude and m/z values into a peak using the analysis module, resulting in a plurality of peaks corresponding to the plurality of predetermined amplitude bands.