Ion Trap Inverse Mathieu Scan Using Constant RF

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Operating ion traps in mass spectrometers requires complex electronics for precise variation of RF signals over time, which is challenging, especially in miniature systems where cost, weight, and power constraints are significant.

Innovation Solution

Implementing a system that uses a constant RF signal and a varying AC signal, with the AC signal's frequency or amplitude adjusted over time, simplifying the electronics required for scanning and allowing for precise control without varying high voltage and high frequency parameters.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If RF signal amplitude or frequency is varied precisely over time to perform mass analysis, then mass spectrometry function is achieved, but electronics complexity increases significantly

Engineering Contradiction:

Improvemass spectrometry functionVSAvoidelectronics complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

Instead of varying the RF signal to achieve mass analysis, the patent inverts the approach by keeping the RF signal constant and varying the AC signal parameters (amplitude or frequency) to achieve the same mass spectrometry function. This inversion transfers the scanning complexity from high-voltage RF electronics to lower-voltage AC electronics, significantly simplifying the overall system.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent changes which parameter is varied: rather than varying RF amplitude or frequency, it varies AC amplitude or frequency while keeping RF constant. This parameter substitution allows mass analysis to be performed with simpler electronics, as AC signal generation is less complex than precise RF signal generation at high voltages and frequencies.

Inventive Principle:

Principle #35Parameter changes

2Productivity

If high voltage and high frequency RF parameters are varied for mass scanning, then mass spectrum can be recorded, but system miniaturization becomes difficult due to complexity constraints

Engineering Contradiction:

Improvemass spectrum recording capabilityVSAvoidsystem miniaturization feasibility

Core Design Contradiction:

ProductivityVSWeight of moving object

Solution Approach 1:

The patent inverts the conventional approach by keeping RF parameters constant and varying AC parameters instead. This allows mass spectrometry functionality to be maintained while avoiding the need for complex high-voltage RF scanning electronics, thereby enabling system miniaturization and reducing weight.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent substitutes complex high-voltage RF signal generation and scanning with simpler AC signal scanning. This replacement of the signal generation mechanism enables miniaturization by eliminating the need for bulky high-voltage power supplies and precise RF frequency synthesizers that would otherwise be required.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Measurement precision

If RF amplitude is scanned to higher values for mass-selective instability, then ions of increasing mass become unstable and detectable, but electronics complexity and power consumption increase

Engineering Contradiction:

Improvemass separation capabilityVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent changes which parameter is scanned: instead of scanning RF amplitude to achieve mass-selective instability, it scans AC amplitude or frequency while keeping RF amplitude constant. This reduces power consumption because AC signals operate at much lower voltages than RF trapping signals, while still achieving the necessary mass separation through resonance ejection.

Inventive Principle:

Principle #35Parameter changes

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 simplifies the electronics needed for mass spectrometry, making it suitable for miniature systems by maintaining constant high voltage and high frequency parameters, reducing complexity and increasing the feasibility of miniaturization while maintaining mass spectrometry capabilities.

Implementation Method 1

If the frequency of this AC signal matches a resonance frequency of ions of a given m/z value, then those ions will acquire energy, and if the time of application and the amplitude of the signal is appropriate, they will leave the ion trap.

Methodology Applied

Scientific EffectResonance: Resonance

Data Source

PatentUS11289321B2Ion traps that apply an inverse mathieu q scan

Publication Date: 2022.03.29 PURDUE RES FOUND

AI summary

The invention generally relates to ion traps and methods of use thereof. In certain embodiments, the invention provides a system that includes a mass spectrometer including an ion trap, and a central processing unit (CPU). The CPU has storage that is coupled to the CPU for storing instructions that when executed by the CPU cause the system to apply a constant radio frequency (RF) signal to the ion trap, and apply a first alternating current (AC) signal to the ion trap the frequency of which varies as a function of time.