Acidic Extraction Reagent for Staphylococcus aureus Antigen
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for detecting Staphylococcus aureus, particularly distinguishing between methicillin-resistant (MRSA) and methicillin-sensitive (MSSA) strains, are inefficient and unreliable due to the need for complex procedures and variable results, especially in extracting and detecting PBP2' and PBP2 antigens.
Innovation Solution
A method using an acidic aqueous solution with specific acids (hydrochloric acid, acetic acid, citric acid, phosphoric acid, or sulfuric acid) at a pH of no higher than 5.0 to simultaneously extract and stabilize PBP2' and PBP2 from Staphylococcus aureus, followed by immunoassay detection to reliably assess whether the strain is MRSA or MSSA.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional culturing methods (dilution method, disc sensitivity test) are used to assess Staphylococcus aureus, then resistance to drugs can be examined, but the culturing time is long and results are variable depending on various factors
Solution Approach 1:
The invention extracts PBP2' antigen from Staphylococcus aureus cells using a specific extraction reagent, separating the detection target from the complex bacterial culture system. This allows direct detection of the resistance marker without performing lengthy culturing procedures, thereby reducing assessment time while maintaining reliability
Solution Approach 2:
The invention replaces the mechanical/biological culturing process with an immunoassay-based detection system. Instead of relying on bacterial growth and phenotypic resistance expression over time, the system uses antibody-antigen recognition to directly detect PBP2' presence, substituting a time-consuming biological process with a faster chemical/biochemical detection method
2Measurement precision
If ultracentrifugation is used to prepare antigen-containing cell membrane fraction for PBP2' detection, then PBP2' can be detected, but the procedure becomes complex and difficult to carry out at ordinary examination facilities
Solution Approach 1:
The invention extracts PBP2' antigen directly from whole cells or simple cell suspensions using a specifically designed extraction reagent, eliminating the need for complex ultracentrifugation steps to isolate cell membranes. The extraction reagent penetrates cells and solubilizes PBP2' directly, simplifying the procedure while maintaining detection accuracy
Solution Approach 2:
The invention changes the extraction conditions by using a specifically formulated reagent system with controlled pH and ionic strength that optimizes PBP2' solubilization and stability. This parameter optimization allows efficient antigen extraction without requiring extreme centrifugal forces, making the procedure suitable for routine laboratories
3Quantity of substance
If urea is used as a denaturing agent for extraction of PBP2' antigen, then the antigen can be extracted, but urea remains in the reaction system during subsequent immunoassay requiring a measuring time of several hours
Solution Approach 1:
The invention uses a disposable extraction reagent system that is designed to be discarded after a single use, eliminating the need for prolonged incubation periods to remove urea. The extraction reagent performs its function of solubilizing PBP2' and is then discarded with the reaction mixture, avoiding contamination issues and extended measurement times
Solution Approach 2:
The invention extracts PBP2' antigen using a mild extraction reagent that does not require urea denaturation. By extracting the antigen in its native or near-native state, the method avoids introducing urea into the system, eliminating the need for extended incubation periods to remove urea before immunoassay
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 efficient and reliable simultaneous extraction and detection of PBP2' and PBP2, enabling accurate differentiation between MRSA and MSSA strains, improving the reliability of Staphylococcus aureus assessment in routine examinations.
Implementation Method 1
using an acidic aqueous solution with specific acids (hydrochloric acid, acetic acid, citric acid, phosphoric acid, or sulfuric acid) at a pH of no higher than 5.0 to simultaneously extract and stabilize PBP2' and PBP2 from Staphylococcus aureus
Implementation Method 2
using an acidic aqueous solution with specific acids (hydrochloric acid, acetic acid, citric acid, phosphoric acid, or sulfuric acid) at a pH of no higher than 5.0 to simultaneously extract and stabilize PBP2' and PBP2 from Staphylococcus aureus
Implementation Method 3
followed by immunoassay detection to reliably assess whether the strain is MRSA or MSSA
Data Source
AI summary
The invention provides a method for extracting a Staphylococcus aureus antigen which comprises using an extraction reagent with a pH of no higher than 5.0, containing one or more acids selected from among hydrochloric acid, acetic acid, citric acid, phosphoric acid, sulfuric acid and nitric acid, to extract a Staphylococcus aureus antigen comprising a methicillin-resistant Staphylococcus aureus antigen and/or a methicillin-sensitive Staphylococcus aureus antigen, from Staphylococcus aureus in a specimen. The invention further provides a method for assessing Staphylococcus aureus.