Self-Contained Biological Indicator for Oxidative Sterilization Readout

Solution Overview

Problem

Existing biological indicators for sterilization processes are costly, time-consuming, and rely on complex procedures such as enzymatic reactions, which are unstable and prone to errors due to environmental conditions, requiring specialized equipment and lengthy incubation times.

Innovation Solution

A self-contained biological indicator using a fluorescence intensity test and colorimetric test after incubation, comprising microbial spores, fluorescent sensor proteins, and a culture medium, which provides immediate and reliable results without enzymatic activity, utilizing a flexible container with a breakable ampoule containing a pH indicator.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If enzymatic activity tests are used to determine sterilization efficacy, then biological indicators can detect viable microorganisms, but the procedure becomes time-consuming and costly requiring specialized equipment

Engineering Contradiction:

Improvesterilization efficacy detectionVSAvoidincubation time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent replaces complex enzymatic activity tests with a fluorescence-based detection system. Fluorescent sensor proteins directly bind to microbial components and emit detectable signals, eliminating the need for lengthy enzymatic reactions and specialized incubation equipment while maintaining reliable sterilization efficacy detection

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces fluorescent sensor proteins as intermediaries that directly interact with microbial structures. These proteins serve as mediators between the sterilized material and detection system, providing immediate fluorescent signals that indicate microbial presence or absence without requiring complex procedural steps

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If enzymatic activity tests are used to determine sterilization efficacy, then biological indicators can detect viable microorganisms, but the procedure becomes costly requiring specialized equipment

Engineering Contradiction:

Improvesterilization efficacy detectionVSAvoidprocedure complexity

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent replaces complex enzymatic activity tests with a fluorescence-based detection system. Fluorescent sensor proteins directly bind to microbial components and emit detectable signals, eliminating the need for lengthy enzymatic reactions and specialized incubation equipment while maintaining reliable sterilization efficacy detection

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent employs disposable fluorescent sensor proteins that are used once for detection and then discarded. This eliminates the need for expensive, specialized equipment and complex procedural setups, making the sterilization verification process more cost-effective and accessible

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Reliability

If enzymatic activity tests are used, then biological indicators can function, but the enzymatic reactions are unstable and prone to errors due to environmental conditions

Engineering Contradiction:

Improvedetection accuracyVSAvoidenzyme stability

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent extracts the detection function from unstable enzymatic systems and implements it through fluorescent sensor proteins. These proteins provide direct, stable fluorescent signals that are not susceptible to environmental variations affecting enzymatic activity, thereby improving detection reliability while maintaining composition stability

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces complex enzymatic activity tests with a fluorescence-based detection system. Fluorescent sensor proteins directly bind to microbial components and emit detectable signals, eliminating the need for lengthy enzymatic reactions and specialized incubation equipment while maintaining reliable sterilization efficacy detection

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 solution offers rapid, cost-effective determination of sterilization efficacy with immediate fluorescence detection and extended readout confirmation, reducing the need for lengthy incubation and specialized equipment, ensuring reliable sterilization assessment.

Implementation Method 1

The at least one fluorescent sensor protein is capable of yielding an immediate optically detectable signal, i.e. a fluorescence signal

Methodology Applied

Scientific EffectFluorescence: Fluorescence

Implementation Method 2

comprises the colorimetric component being capable of undergoing an optically detectable color change in the presence of microbial growth

Methodology Applied

Scientific EffectColor change:

Implementation Method 3

employing both an immediate fluorescence signal detection and a colorimetric test after a certain incubation time... capable of yielding a different optically detectable signal... when the at least one fluorescent sensor protein is in a denatured state after the oxidative sterilization process

Methodology Applied

Scientific EffectOxidation: Oxidation

Data Source

PatentUS12448642B2Biological indicator for determining the efficacy of an oxidative sterilization process and methods of use

Publication Date: 2025.10.21 TERRAGENE LLC

AI summary

A biological indicator for determining the efficacy of an oxidative sterilization process, and its methods of use. The biological indicator comprises a set of microbial spores, at least one fluorescent sensor protein, and a culture medium, the fluorescent sensor protein being capable of yielding an optically detectable signal when the fluorescent sensor protein is not in a denatured state due to the oxidative sterilization process, and a different optically detectable signal when the fluorescent sensor protein is in a denatured state after the oxidative sterilization process.