Needle Assembly Ion Introduction for Mass Spectrometers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for introducing samples into mass spectrometers are cumbersome and expensive, requiring high gas flow and additional vacuum locks, which complicates the process and increases costs.
Innovation Solution
A method involving a needle assembly with a sample probe that is inserted through an orifice into a sub-atmospheric pressure region of the spectrometer, allowing for desorption and ionization within the ion guide or ion trap, minimizing gas introduction and eliminating the need for extra vacuum locks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a larger orifice is used to pass more ions into the mass spectrometer, then ion transmission efficiency is improved, but gas flow into the mass spectrometer increases requiring more expensive vacuum pumping equipment
Solution Approach 1:
The sample is introduced into a vacuum lock chamber before the main vacuum region, and the vacuum lock is partially evacuated in advance. This preliminary action allows the sample to be introduced without requiring the main vacuum chamber to handle large gas loads, thus maintaining ion transmission efficiency while reducing vacuum pumping requirements.
Solution Approach 2:
The vacuum system is segmented into separate regions: a vacuum lock chamber for sample introduction and a main vacuum chamber for mass analysis. This segmentation isolates the gas load from sample introduction to a specific region, allowing independent vacuum management and reducing the overall pumping requirements for the main analytical region.
2Loss of energy
If a vacuum lock is used to introduce samples into the mass spectrometer, then gas load on the vacuum system is reduced, but the device becomes mechanically cumbersome and expensive requiring additional rough pumping
Solution Approach 1:
The vacuum lock chamber is integrated into the main vacuum chamber as a single interconnected vacuum system rather than separate isolated chambers. This merging eliminates the need for additional rough pumping equipment and complex mechanical interfaces while still providing the benefit of reduced gas load to the main vacuum region.
Solution Approach 2:
The vacuum lock chamber acts as an intermediary region between the atmospheric sample introduction port and the main vacuum chamber. It partially evacuates to serve as a transition zone, reducing the gas load on the main vacuum system while avoiding the need for complex mechanical vacuum locks.
3Reliability
If atmospheric pressure ionisation sources are used to ionise low volatility analytes, then ionisation capability is improved, but gas flow into the mass spectrometer increases requiring expensive vacuum pumping
Solution Approach 1:
The ionisation process is extracted from the atmospheric pressure region and moved into the vacuum lock chamber which is partially evacuated. This allows atmospheric pressure ionisation techniques to be used for low volatility analytes while the vacuum environment captures the ions with minimal gas load on the main mass spectrometer vacuum system.
Solution Approach 2:
The vacuum lock chamber serves as an intermediary environment that allows atmospheric pressure ionisation to occur while maintaining a vacuum barrier to the main mass spectrometer. Ions are generated in the lock chamber and then transferred to the main vacuum region, separating the ionisation function from the vacuum maintenance function.
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 efficiently introduces samples into the spectrometer with minimal gas load, reducing the need for expensive vacuum pumping and mechanical complexity, while allowing for effective ion capture and analysis.
Implementation Method 1
providing a spectrometer comprising an orifice between an atmospheric pressure region and a sub-atmospheric pressure region of the spectrometer
Implementation Method 2
desorbing the sample from the needle assembly within the sub-atmospheric pressure region
Implementation Method 3
ionising the sample within the sub-atmospheric pressure region so as to generate ions that enter the ion guide or ion trap
Data Source
AI summary
A method of mass or ion mobility spectrometry is disclosed. The method comprises providing a spectrometer comprising an orifice between an atmospheric and a sub-atmospheric pressure region of the spectrometer, wherein the latter comprises an ion guide or ion trap; providing a sample probe comprising a needle assembly on which a sample is deposited or that is supplied with a sample; inserting the needle assembly through the orifice into the sub-atmospheric pressure region so that the sample is arranged within or adjacent to the ion guide or trap in the sub-atmospheric pressure region; and then desorbing the sample from the needle assembly within the sub-atmospheric pressure region and/or ionizing the sample within the sub-atmospheric pressure region so as to generate ions that enter the ion guide or ion trap. The proximity of the sample to the ion guide or trap allows analyte ions from the sample to be captured efficiently.