Laserspray Ionization Vacuum Mass Spectrometry

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current MALDI mass spectrometry techniques face limitations in analyzing high-mass compounds due to the production of singly charged ions, which restricts mass analysis and fragmentation methods, and are hindered by chemical background and sensitivity issues, especially at intermediate and atmospheric pressures.

Innovation Solution

The use of laserspray ionization (LSI) at vacuum conditions, combined with specific matrix compounds and pressure drops, to produce multiply-charged ions (MCIs) directly from surfaces, facilitating improved analysis of macromolecular structures with enhanced sensitivity and fragmentation capabilities.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If MALDI operates at atmospheric pressure with singly charged ions, then data interpretation is simple, but mass analysis of high-mass compounds is limited

Engineering Contradiction:

Improvedata interpretation simplicityVSAvoidmass analysis capability

Core Design Contradiction:

Ease of operationVSAdaptability or versatility

Solution Approach 1:

The patent changes the pressure parameter from atmospheric to vacuum conditions, and changes the ionization mode from singly charged to multiply charged ions. This allows high-mass compounds to be analyzed while maintaining data interpretation simplicity through the use of matrix-assisted laser desorption/ionization with vacuum conditions and multiply charged ion detection

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent uses composite matrix materials (such as 2,5-dihydroxyacetophenone and 4,6-dinitropyrogallol) that enable both vacuum compatibility and multiply charged ion production. These composite approaches combine matrix compounds with specific physical conditions to achieve multiple objectives simultaneously

Inventive Principle:

Principle #40Composite materials

2Adaptability or versatility

If ESI produces multiply charged ions, then mass range is extended and fragmentation methods are enabled, but sprayable conditions are required and system complexity increases

Engineering Contradiction:

Improvemass range capabilityVSAvoidsystem complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical spray system of ESI with a laser-based desorption system. Instead of using high voltage and liquid spray to produce multiply charged ions, the patent uses laser irradiation of solid-state matrix-analyte associations in vacuum conditions, eliminating the need for sprayable conditions while maintaining multiply charged ion production

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent utilizes phase transition from solid state to gas phase through laser-induced desorption. The matrix-analyte association transitions from solid to vapor phase, enabling ion production without liquid spray, thereby simplifying the system while extending mass range capability

Inventive Principle:

Principle #36Phase transitions

3Ease of operation

If LSI is used at atmospheric pressure, then highly charged ions are produced without voltage, but sensitivity and chemical background issues persist

Engineering Contradiction:

Improveion production without voltageVSAvoidsensitivity

Core Design Contradiction:

Ease of operationVSMeasurement precision

Solution Approach 1:

The patent uses vacuum as an inert environment to replace atmospheric pressure conditions. In vacuum, chemical background interference is minimized, and sensitivity is improved while maintaining the ability to produce highly charged ions without applied voltage through laser irradiation of the matrix-analyte association

Inventive Principle:

Principle #39Inert atmosphere (Inert environment)

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 allows for nearly identical mass spectra and drift time distributions of peptides and proteins from tissue and solution analyses, extending mass range and enabling powerful fragmentation techniques like ETD, while minimizing chemical background and improving data interpretation.

Implementation Method 1

contacting the matrix/analyte association with a laser beam

Methodology Applied

Scientific EffectLaser ablation: Laser Ablation

Implementation Method 2

laserspray ionization (LSI) at vacuum conditions, combined with specific matrix compounds and pressure drops, to produce multiply-charged ions

Methodology Applied

Scientific EffectIonization: Ionisation

Implementation Method 3

allowing entry of the matrix/analyte association into a mass spectrometer comprising an IP zone wherein the matrix/analyte or matrix/analyte association is exposed to a decrease in pressure following the entry thereby producing the MCIs

Methodology Applied

Scientific EffectPressure drop: Pressure Drop

Data Source

PatentUS9177773B2Systems and methods extending the laserspray ionization mass spectrometry concept from atmospheric pressure to vacuum

Publication Date: 2015.11.03 WAYNE STATE UNIV

AI summary

Disclosed herein are systems and methods that allow analysis of macromolecular structures using laserspray ionization at intermediate pressure or high vacuum using commercially available mass spectrometers with or without modification and with the application of heat. The systems and methods produce multiply-charged ions for improved analysis in mass spectrometry.