Ion Trap Intensity Scaling via Variable Gate Offset
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional mass spectrometry data scaling techniques are inadequate as they fail to accurately normalize ion intensity across a wide range of mass-to-charge ratios due to constant gate offset times, leading to inconsistent ion trapping and data inaccuracy.
Innovation Solution
The method involves adjusting ion intensity values based on the time needed by the ion trap to begin collecting ions with specific mass-to-charge values, using equations to calculate scaled intensity and total ion current, ensuring accurate data scaling across the entire m/z spectrum by accounting for varying gate offset times.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a constant gate offset time is used for the entire m/z range, then the device operation is simplified, but the ion trapping consistency and data accuracy deteriorate across different m/z values
Solution Approach 1:
The patent changes the gate offset time parameter from a constant value to a variable value that depends on the m/z ratio. Specifically, different gate offset times are assigned to different m/z ranges, allowing optimal ion trapping for each mass range while maintaining operational simplicity through automated selection based on the m/z value.
Solution Approach 2:
The patent applies different gate offset time values to different local regions of the m/z spectrum. By segmenting the m/z range and assigning specific gate offset times to each segment, the system optimizes ion trapping locally for each m/z range rather than using a single global value, thereby improving measurement precision across the entire spectrum.
2Reliability
If the gate offset time is increased to ensure ion collection for high m/z values, then the ion trapping for high m/z improves, but the overall scan time and productivity decrease
Solution Approach 1:
The patent dynamically adjusts the gate offset time parameter based on the m/z value being measured. For high m/z values, larger gate offset times are used to ensure complete ion collection, while for low m/z values, smaller gate offset times are used to maintain fast scan speeds. This adaptive parameter adjustment resolves the contradiction between reliability and productivity.
Solution Approach 2:
The patent makes the gate offset time dynamic rather than static. The gate offset time changes automatically according to the m/z range being scanned, allowing the system to optimize both ion collection completeness and scan speed for different mass ranges, thereby improving overall productivity without sacrificing reliability.
3Measurement precision
If the ion trap is filled to maximum capacity to improve sensitivity, then the detection limit improves, but space charge effects increase causing data inaccuracy
Solution Approach 1:
The patent applies different scaling approaches to different m/z ranges within the ion trap. By segmenting the m/z spectrum and applying appropriate scaling factors to each segment, the system can accurately quantify ions across the full range while accounting for local space charge effects, thereby maintaining measurement precision without being limited by maximum trap capacity constraints.
Data Source
Figure 1~5
Figure 3
Figure 4
AI summary
A method includes: accumulating ions having a plurality of m/z values in an ion trap during a time interval; deriving from the accumulated ions a respective intensity value for each of the m/z values; and adjusting each of the intensity values as a function of the time needed by the ion trap to begin collecting ions with the corresponding m/z value. According to a different aspect, an apparatus includes a first portion with an ion trap, and a second portion. The second portion causes the ion trap to accumulate ions with a plurality of m/z values during a time interval, derives from the accumulated ions in the ion trap a respective intensity value for each of the m/z values, and adjusts each of the intensity values as a function of the time needed by the ion trap to begin collecting ions with the corresponding m/z value.