In Situ Peracetic Acid Generation for Medical Sterilization

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing antimicrobial systems for sterilizing medical instruments face issues with decomposition, corrosiveness, and inconsistent delivery of peracetic acid, requiring additional buffers and venting systems that pose handling and storage challenges.

Innovation Solution

A water-soluble peracetic acid precursor, such as diacetyl methylamine, is combined with a dry peroxide source like sodium percarbonate in separate compartments within a specialized containment cup, reacting in situ to form peracetic acid, reducing decomposition and handling issues while maintaining effective biocidal activity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If peracetic acid is used as the sterilizing agent, then biocidal activity is achieved, but decomposition occurs leading to loss of effectiveness and generation of oxygen gas requiring venting

Engineering Contradiction:

Improvebiocidal activityVSAvoiddecomposition of peracetic acid

Core Design Contradiction:

ReliabilityVSLoss of substance

Solution Approach 1:

The peracetic acid sterilizing system is divided into three separate components: peracetic acid precursor, peroxide source, and water-soluble buffer. These components are stored separately and combined only during the sterilization cycle, preventing premature decomposition and allowing each component to be optimized independently for stability and effectiveness.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The peracetic acid precursor and peroxide source are prepared and stored in advance in stable forms that do not require venting. The actual peracetic acid formation occurs preliminarily mixed with buffer solution during the sterilization cycle, ensuring the active agent is generated only when needed and under controlled conditions, minimizing decomposition.

Inventive Principle:

Principle #10Preliminary action

2Duration of action of stationary object

If sulfuric acid is added to peracetic acid to minimize decomposition, then shelf life is improved, but corrosiveness increases requiring additional buffers and corrosion inhibitors

Engineering Contradiction:

Improveshelf lifeVSAvoidcorrosiveness

Core Design Contradiction:

Duration of action of stationary objectVSObject-affected harmful factors

Solution Approach 1:

The system changes the pH parameter dynamically by separating the acidic component (peracetic acid precursor) from the buffering component. During storage, components are kept separate with the buffer maintaining a pH of 6-8 for low corrosiveness. During sterilization, the precursor reacts with peroxide to generate peracetic acid in situ at the required low pH for effectiveness, achieving both long shelf life and high biocidal activity without sustained corrosiveness.

Inventive Principle:

Principle #35Parameter changes

3Stress or pressure

If vents are added to containers to permit oxygen escape, then pressure buildup is prevented, but noxious peracetic acid vapors can escape into the atmosphere

Engineering Contradiction:

Improvepressure buildupVSAvoidnoxious vapors

Core Design Contradiction:

Stress or pressureVSObject-generated harmful factors

Solution Approach 1:

The harmful peracetic acid vapor generation is extracted and eliminated by changing from storing ready-made peracetic acid to storing stable precursors (peracetic acid precursor and peroxide source) that do not emit noxious vapors during storage. The peracetic acid is generated in situ only when needed, and the buffer system maintains pH conditions that minimize vapor pressure, allowing safe operation without vents.

Inventive Principle:

Principle #2Taking out (Extraction)

4Productivity

If peracetic acid is delivered in liquid form, then rapid dissolution occurs, but decomposition rate increases and handling becomes more difficult

Engineering Contradiction:

Improvedissolution rateVSAvoidstability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The system applies different physical states to different components based on their specific functions: the peroxide source is in solid form for maximum stability and controlled dissolution, the peracetic acid precursor is in liquid form for rapid mixing and reaction, and the buffer is in liquid form for immediate pH control. This localized optimization of physical state for each component achieves both rapid dissolution and stability.

Inventive Principle:

Principle #3Local quality

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 enhances the shelf life and stability of the antimicrobial solution, reduces the need for corrosion inhibitors, and ensures consistent delivery of peracetic acid, achieving commercial sterility in medical instruments without the drawbacks of traditional systems.

Implementation Method 1

Methodology Applied

Scientific EffectChemical reaction: Chemical Bonding

Data Source

PatentUS8920715B2Sterilant composition and system

Publication Date: 2014.12.30 HEMOSTASIS LLC

AI summary

An antimicrobial solution for disinfecting instruments in an automatic sterilization device, the solution comprising: a peracid reaction product formed in situ from combining a liquid acetyl donor with a solid source of peroxide, wherein the in situ reaction takes place in the sterilization device, along with a containment and delivery ampule for use in an automatic sterilization device, and methods for disinfecting a medical instrument employing the inventive antibacterial solution.