Stabilized Protease-RNase Mixture for RNA-Free DNA Purification

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current DNA extraction methods require separate addition of proteases and RNases to avoid inactivation, leading to clutter and potential errors, and there is a need for a stable reagent mixture that can maintain enzymatic activity over extended storage periods.

Innovation Solution

A reagent mixture comprising a protease, an RNase, and a detergent, such as proteinase K, RNase A, and N-lauroylsarcosine sodium salt, that remains stable for at least 24 hours at 4°C, allowing for simultaneous cell lysis, protein digestion, and RNA degradation without substantial inactivation of the RNase.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If protease and RNase are added separately to avoid inactivation, then enzymatic activity is preserved, but device complexity and ease of operation deteriorate due to multiple containers and steps

Engineering Contradiction:
Improveenzymatic activity preservationVSAvoidnumber of containers and steps
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines protease and RNase into a single reagent mixture that can be added in one step. The key innovation is formulating both enzymes in the same buffer solution with optimized pH and ionic conditions that prevent the protease from degrading the RNase, thereby reducing the number of separate addition steps while maintaining both enzymatic activities.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The reagent mixture serves multiple functions simultaneously: it provides both proteolytic activity (from protease) and RNase activity (from RNase) in a single formulation. This multi-functional approach eliminates the need for separate reagent additions and simplifies the overall DNA purification protocol.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Ease of operation

If protease and RNase are combined in a single mixture, then ease of operation improves, but reliability deteriorates due to expected inactivation of RNase by protease

Engineering Contradiction:
Improvesingle reagent additionVSAvoidRNase activity stability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent optimizes the buffer parameters including pH (maintained around neutral to slightly alkaline), ionic strength, and presence of specific ions that create an environment where the protease is less active or where the RNase is protected from degradation. This parameter optimization ensures both enzymes remain stable and active when combined.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The buffer components act as intermediaries that protect the RNase from degradation by the protease. Specific buffer ingredients may chelate metal ions required for protease activity or create steric protection, thereby mediating the interaction between the two enzymes to prevent harmful degradation while allowing both to function.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Productivity

If reagent mixture is stored for extended periods, then productivity improves through advance preparation, but reliability deteriorates due to enzyme inactivation

Engineering Contradiction:
Improveadvance preparation capabilityVSAvoidenzymatic activity over time
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The buffer formulation includes stabilizing agents and protective components that are added beforehand to cushion against degradation during storage. These pre-added protective elements prevent enzyme inactivation during extended storage periods, allowing the reagent mixture to be prepared in advance without significant loss of enzymatic activity.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

Solution Approach 2:

The reagent mixture is formulated as a composite system combining protease, RNase, buffer components, and stabilizing agents in specific proportions. This composite formulation creates a synergistic effect where the various components work together to maintain enzyme stability during storage, enabling long-term shelf life while preserving full enzymatic activity upon use.

Inventive Principle:
Principle #40Composite materials

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 provides a stable, single reagent mixture for RNA-free DNA purification, reducing the need for multiple containers and steps, and maintaining enzymatic activity for extended storage periods, making it suitable for commercial kits and biotechnological applications.

Implementation Method 1

enzymes for the degradation of RNA or protein

Methodology Applied
Scientific EffectEnzymatic degradation: Enzyme

Implementation Method 2

protease... for the degradation of... protein

Methodology Applied
Scientific EffectProteolysis: Hydrolysis

Implementation Method 3

enzymes for the degradation of RNA or protein

Methodology Applied
Scientific EffectEnzymatic degradation: Enzyme

Implementation Method 4

RNase... for the degradation of RNA

Methodology Applied
Scientific EffectRNA hydrolysis: Hydrolysis

Implementation Method 5

detergent... for simultaneous cell lysis

Methodology Applied
Scientific EffectSurfactant action: Surfactant

Data Source

PatentUS8652821B2Stabilized protease-containing solutions for purifying RNA-free DNA
Publication Date: 2014.02.18 BIO RAD LABORATORIES INC

AI summary

The present invention provides compositions and methods for purifying RNA-free DNA from a sample.