Coated Blade Spray Fluid Barrier for Stable Negative Ionization

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Substrate-based electrospray ionization techniques in negative mode face challenges such as corona discharge, high background noise, and unstable spray, particularly when analyzing complex biological samples like blood and urine, due to ionization inhibition by salts, leading to high relative standard deviation (RSD) in mass spectrometry analysis.

Innovation Solution

Incorporating a fluid barrier near the ionization tip in the coated blade spray (CBS) device to prevent solvent movement away from the ionization tip, enhancing solvent flow stability and reducing RSD by using gravity and surface tension effects, thereby improving the stability of the electrospray ionization process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If substrate-based electrospray ionization is used in negative mode, then ionization of analytes can be achieved, but corona discharge and unstable spray occur due to salt interference

Engineering Contradiction:

Improveionization stabilityVSAvoidcorona discharge and background noise

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The blade is divided into distinct functional zones: a hydrophobic portion for salt repulsion and a hydrophilic portion for solvent attraction. This segmentation allows the device to simultaneously manage salt interference and solvent delivery, resolving the contradiction between achieving stable ionization and preventing corona discharge.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the blade are given different surface properties: the leading edge and portions away from the ionization tip are made hydrophobic to repel salts, while the region near the ionization tip is made hydrophilic to attract and stabilize the desorption solvent. This local differentiation enables the blade to handle both salt rejection and solvent stabilization functions in appropriate locations.

Inventive Principle:

Principle #3Local quality

2Measurement precision

If desorption solvent is applied to the blade, then analyte desorption can occur, but solvent movement away from the ionization tip causes high RSD

Engineering Contradiction:

ImproveRSDVSAvoidsolvent flow stability

Core Design Contradiction:

Measurement precisionVSStability of the object's composition

Solution Approach 1:

The blade surface is engineered with localized hydrophilic regions near the ionization tip that selectively attract and retain the desorption solvent through capillary action. This ensures the solvent remains concentrated where needed for consistent analyte desorption and ionization, preventing the solvent flow instability that causes high RSD.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent replaces mechanical solvent delivery systems with surface tension-based capillary flow control. The hydrophilic/hydrophobic pattern on the blade surface automatically regulates solvent movement and positioning without mechanical intervention, achieving stable solvent flow and low RSD.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Quantity of substance

If salts are present in the sample, then complete analyte extraction can be achieved, but ionization inhibition occurs in negative mode

Engineering Contradiction:

Improveanalyte extraction efficiencyVSAvoidionization efficiency

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The blade is segmented into hydrophobic zones for salt repulsion and hydrophilic zones for analyte desorption. This spatial separation allows salts to be excluded from the ionization region while analytes are efficiently extracted and desorbed, resolving the contradiction between complete extraction and ionization efficiency.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent converts the harmful effect of salt presence into a beneficial separation mechanism. Salts are naturally repelled by the hydrophobic portions of the blade and excluded from the hydrophilic ionization zone, while analytes are selectively desorbed. This transforms salt interference into a built-in purification function.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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

The implementation of a fluid barrier reduces the RSD to less than 10% in negative ionization mode for the analysis of drugs of abuse in saliva samples, achieving more stable and reproducible mass spectrometry results without the need for internal standards.

Implementation Method 1

enhancing solvent flow stability and reducing RSD by using gravity and surface tension effects

Methodology Applied

Scientific EffectGravity: Gravitation

Implementation Method 2

enhancing solvent flow stability and reducing RSD by using gravity and surface tension effects

Methodology Applied

Scientific EffectSurface tension: Surface Tension

Data Source

PatentUS20240087867A1Method and device for sample introduction for mass spectrometry

Publication Date: 2024.03.14 JP SCI LTD

AI summary

The present disclosure provides a device for generating ionized molecules of interest for analysis in a mass spectrometer. The molecules of interest are desorbed from the device into a desorption solvent. The device includes: a solid substrate having a spray-ionization end and a holding end, the substrate being sized and configured to hold the solvent at the spray-ionization end; and a fluid barrier configured to reduce movement of at least some of the solvent from the spray-ionization end towards the holding end. Methods for analyzing molecules in or from a sample are also provided.