Immunoprecipitation Mass Spectrometry Charge Neutralization
Solution Overview
Problem
Current methods for detecting biomarker molecules, such as amyloid peptides, in clinical samples using mass spectrometry face challenges in identifying captured molecules and distinguishing between different peptides, leading to low detection sensitivity and inability to examine the form of molecules, especially in the SELDI method.
Innovation Solution
A method involving immunoprecipitation using an antibody-bound carrier, followed by washing with a charge-neutralizing agent to maintain the form of the immunoprecipitate and prevent ionization suppression, allowing direct mass spectrometry analysis, which enhances detection sensitivity and ability to identify and quantify biomarkers, including amyloid (1-40)/(1-42) ratio.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If SELDI method is used to capture molecules on chip surface, then molecule capture is achieved, but detection sensitivity is low and ability to identify molecule form is lost
Solution Approach 1:
The patent extracts the captured molecules from the chip surface by eluting them with a suitable buffer, then analyzes the eluted molecules using MALDI-TOF mass spectrometry. This extraction process recovers the molecule form information that was lost during chip-based capture, while maintaining the detection sensitivity benefits of the SELDI method.
Solution Approach 2:
The patent introduces an intermediary elution buffer that mediates between the chip-captured molecules and the mass spectrometry analysis system. This buffer serves as a carrier that preserves molecule form information while enabling transfer to the analysis platform, resolving the contradiction between capture efficiency and information retention.
2Adaptability or versatility
If multiple types of chips are used to capture different molecules, then coverage of biomarkers is improved, but device complexity and operation difficulty increase
Solution Approach 1:
The patent employs a universal elution buffer composition that can effectively elute various types of molecules captured on different chip surfaces. This single buffer system serves multiple functions across different chip types, eliminating the need for chip-specific elution protocols and reducing operational complexity while maintaining broad biomarker coverage.
Solution Approach 2:
The patent segments the analysis process into distinct functional modules: capture phase (using various chip types), elution phase (using universal buffer), and analysis phase (MALDI-TOF MS). This segmentation allows each module to be optimized independently, enabling versatile biomarker detection without proportionally increasing overall system complexity.
3Measurement precision
If immunoprecipitation is performed without proper washing, then detection sensitivity is improved, but ionization suppression occurs in mass spectrometry
Solution Approach 1:
The patent carefully controls the parameters of the washing buffer, including pH, ionic strength, and composition, to achieve optimal balance. The washing buffer is designed with specific parameters that enable effective removal of interfering substances without disrupting the antigen-antibody complexes, thus maintaining detection sensitivity while preventing ionization suppression in the subsequent mass spectrometry analysis.
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 improves detection sensitivity to low ng/mL levels, enabling the analysis of clinically significant molecules and their interactions, and provides a versatile system for various biomarker tests, applicable in clinical settings with general IP beads and MALDI-based mass spectrometry, surpassing conventional methods like SELDI and ELISA.
Implementation Method 1
concentrating the biological molecule in the sample by immunoprecipitation using an antibody-bound carrier or a carrier to which a molecule capable of specifically binding to an antibody is bound
Implementation Method 2
washing an immunoprecipitate of the biological molecule by using an aqueous solution containing a charge neutralizing agent as a washing liquid
Data Source
Figure 1
Figure 2
Figure 3
AI summary
It is intended to provide an analysis method for a biological sample with clinical significance, which is a system being simple to such an extent that it can be applied to a clinical field, and capable of capping a molecule ionization suppression in mass spectrometry. Mass spectrometry of a biological sample using immunoprecipitation, comprising the steps of: preparing a sample containing an objective biological molecule; concentrating the biological molecule in the sample by immunoprecipitation using an antibody-bound carrier or a carrier to which a molecule capable of specifically binding to an antibody is bound; washing an immunoprecipitate of the biological molecule by using an aqueous solution containing a charge neutralizing agent as a Mashing liquid; and detecting the biological molecule by subjecting the washed immunoprecipitate to mass spectrometry.