Sterilization System with Movable Boundary for Lumen Penetration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Low-temperature hydrogen peroxide vapor sterilization systems face challenges in effectively sterilizing objects with long, narrow lumens due to degradation and limited penetration, as hydrogen peroxide vapor degrades upon contact with lumen materials and is hindered by water droplets, restricting the size and length of lumens that can be sterilized.
Innovation Solution
A variable volume sterilization system with a movable boundary, such as a piston or bellows, that controls pressure variations within the sterilization chamber to enhance hydrogen peroxide vapor penetration by removing degraded vapor, forcing concentrated vapor into lumens, and controlling flow types to preferentially move non-degraded vapor deeper into the lumen.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If hydrogen peroxide vapor is used to sterilize long narrow lumens, then sterilization effectiveness is reduced, but increasing vapor concentration increases material degradation
Solution Approach 1:
The patent employs a movable boundary (piston or bellows) that dynamically changes the volume of the sterilization chamber during the sterilization process. This dynamic volume adjustment creates pressure variations that enhance vapor penetration into lumens without requiring increased vapor concentration, thereby maintaining material compatibility while improving sterilization effectiveness.
Solution Approach 2:
The system changes physical parameters (volume and pressure) of the sterilization chamber during operation. By reducing chamber volume, pressure increases and forces hydrogen peroxide vapor deeper into lumens. This parameter change approach achieves better sterilization penetration without increasing the harmful concentration of vapor that would cause material degradation.
2Length of moving object
If chamber volume is reduced to increase vapor concentration, then penetration into lumens improves, but material degradation increases
Solution Approach 1:
The patent uses controlled volume reduction to change pressure parameters, which enhances vapor penetration depth into lumens. The key distinction is that the volume reduction is controlled and temporary, creating pressure waves that push vapor forward without sustaining high concentrations that would cause material degradation.
Solution Approach 2:
The movable boundary creates periodic compression and expansion cycles within the chamber. These periodic actions generate pressure variations that repeatedly push vapor into lumens and then allow decomposition products to be evacuated, achieving deep penetration without continuous exposure to high concentrations that would degrade materials.
3Duration of action of moving object
If degraded vapor is allowed to accumulate, then sterilization time is reduced, but sterilization effectiveness decreases
Solution Approach 1:
The patent extracts degraded hydrogen peroxide vapor (which has decomposed into water and oxygen) from the sterilization chamber through the movable boundary system. By removing degraded vapor and replacing it with fresh sterilant vapor, the system maintains sterilization effectiveness over extended periods without allowing harmful accumulation of decomposition products.
Solution Approach 2:
The system maintains continuous sterilization effectiveness by continuously removing degraded vapor and replenishing active sterilant. The movable boundary enables continuous circulation and renewal of the vapor environment, ensuring that sterilization action remains effective throughout the extended sterilization cycle without interruption or loss of potency.
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 full sterilization of objects with long, narrow lumens without increasing hydrogen peroxide concentration, maintaining material compatibility and ensuring effective sterilization by redistributing vapor concentration and controlling flow dynamics within the lumen.
Implementation Method 1
The varying volume of the sterilization area is achieved by providing a movable boundary... The motion of the movable boundary can be controlled to produce desired compression and expansion of the sterilization area... to enhance the sterilization process
Implementation Method 2
hydrogen peroxide vapor degrades to water and oxygen over time when coming in contact with many materials used to form the surface of such lumens
Implementation Method 3
These methods have been described in prior art to increase the vapor concentration above that of 59% hydrogen peroxide. These are generally methods to remove some of the water vapor with a vacuum pump
Data Source
AI summary
An apparatus and method for achieving low temperature vapor sterilization of objects which may involve objects having a lumen. Following evacuation of the sterilization chamber and the introduction of a vaporous or gaseous sterilant, the volume of the chamber is changed by actuation of a movable boundary in the chamber to increase and decrease the pressure in the chamber thus driving the sterilant into and out of such lumens.