Mass Spectrometer Ion Optics Cleanliness via Time-Segmented Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Mass spectrometers face challenges in detecting ion optics cleanliness, as contamination affects ion transit time and signal intensity, leading to potential system failures during sample analysis, with existing System Suitability tests often failing to detect issues until they become severe.
Innovation Solution
A mass spectrometer system that switches ion optics between transmission modes to determine ion signal intensity at different times, calculating differences and rate of change to indicate cleanliness, with processor and circuitry configured to produce outputs for maintenance notifications based on threshold values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If System Suitability tests average the ion signal over the entire dwell time, then the test is simple to perform, but early contamination issues are not detected
Solution Approach 1:
The patent divides the ion signal measurement into multiple time segments within the dwell time period. Instead of measuring the average signal over the entire dwell time, the system measures ion signal intensity at multiple specific time points (e.g., first time point, second time point, etc.) and compares these segmented measurements to detect contamination-induced variations in ion transit time.
Solution Approach 2:
The patent performs preliminary measurements of ion signal intensity at multiple time points before making a contamination determination. By collecting data at several time points during the dwell time and comparing these preliminary measurements, the system can detect early signs of contamination that would be masked by a simple average measurement.
2Reliability
If ion optics are monitored continuously for cleanliness, then early detection is achieved, but system complexity increases
Solution Approach 1:
The mass spectrometer performs self-diagnosis by using its own existing measurement capabilities to detect ion optics contamination. The system leverages routine ion signal measurements already being performed for analytical purposes and applies a contamination detection algorithm to these existing data, eliminating the need for separate dedicated monitoring hardware.
Solution Approach 2:
The patent makes the ion signal measurement serve dual purposes: both analytical measurement and contamination detection. The same ion signal data collected for analytical purposes is also used to assess ion optics cleanliness, allowing one measurement system to perform multiple functions without adding dedicated monitoring equipment.
3Measurement precision
If ion signal intensity is measured at multiple time points, then contamination detection accuracy improves, but data processing requirements increase
Solution Approach 1:
Instead of complex spectral deconvolution to separate overlapping ion signals, the patent inverts the approach by measuring at strategically selected time points where contamination effects manifest as distinct temporal patterns. The method compares intensity ratios or differences at these inverted time points to detect contamination, simplifying the data processing compared to traditional spectral analysis.
Data Source
AI summary
A mass spectrometer is disclosed comprising: an ion detector; ion optics for guiding ions to the ion detector; one or more voltage supply for supplying voltages to said ion optics; control circuitry for controlling the one or more voltage supply so as to switch the ion optics between operating in a first mode in which the ion optics are unable to transmit ions having a first mass to charge ratio or first polarity to the ion detector and a second mode in which the ion optics are able to transmit ions having said first mass to charge ratio or first polarity to the ion detector for a time period; and to repeatedly switch between the first and second modes a plurality of times; and a processor and circuitry configured to: (i) determine the intensity of an ion signal detected by the detector at a first time in each of the time periods that the ion optics are in the second mode; and (ii) determine the intensity of the ion signal detected by the detector at a second, later time in each of the time periods that the ion optics are in the second mode.