Slab Gel Cassette Stabilization Against Swelling Bowing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Slab gel cassettes experience swelling due to water absorption from buffer solutions, leading to outward bowing of plates and uneven pore sizes, which causes 'smiling' effects in electrophoresis results, reducing reproducibility and accuracy. Additionally, the formation of 'webbing' between comb teeth and cassette walls complicates sample loading.

Innovation Solution

A comb with hook-like projections that engage the cassette plates to prevent bowing, combined with structural features that maintain a consistent gap width and reduced pressure inside the gel cavity, along with alternative materials and constructions like interlocking profiles and external rigidifying enclosures, to stabilize the cassette and prevent swelling-induced distortion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Duration of action of stationary object

If the gel is stored in buffer solution for packaging or storage purposes, then the gel absorbs water and swells, but this causes the plates to bow outward and creates uneven pore sizes leading to smiling effects

Engineering Contradiction:
Improvestorage durationVSAvoidplate flatness
Core Design Contradiction:
Duration of action of stationary objectVSShape

Solution Approach 1:

The patent applies preliminary anti-action by using a rigid enclosure that pre-establishes counteracting forces against the expected swelling pressure of the gel during storage. The enclosure is designed with sufficient rigidity to resist the outward bowing force that will be generated when the gel absorbs buffer solution over time, thereby preventing plate deformation before it occurs.

Inventive Principle:
Principle #9Preliminary anti-action

Solution Approach 2:

The rigid enclosure acts as an intermediary between the swelling gel and the external environment. It mediates the interaction by containing the gel while resisting its swelling forces, preventing direct transmission of swelling pressure to the plates and thus maintaining plate flatness during storage.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If the comb material inhibits polymerization at its surface to prevent gel adhesion, then the comb can be removed easily, but this also inhibits polymerization in spaces between teeth and cassette walls causing webbing formation

Engineering Contradiction:
Improvecomb removal easeVSAvoidwebbing formation
Core Design Contradiction:
Ease of operationVSObject-generated harmful factors

Solution Approach 1:

The patent applies local quality by differentiating the anti-polymerization properties in different spatial locations. The comb surface maintains strong anti-polymerization characteristics to prevent gel adhesion and enable easy removal, while the spaces between teeth and cassette walls are designed with reduced anti-polymerization effects or different geometries that allow controlled polymerization, preventing webbing formation.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The comb structure is segmented into teeth with specific geometries that create controlled spaces. The segmentation allows different regions to have different polymerization characteristics - the tooth surfaces inhibit polymerization for easy removal, while the spaced geometry between teeth permits adequate polymerization to prevent webbing.

Inventive Principle:
Principle #1Segmentation

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 effectively maintains the integrity of the cassette plates, preventing bowing and ensuring consistent pore sizes, thereby improving the reproducibility and accuracy of electrophoresis results and facilitating easier sample loading by preventing webbing formation.

Implementation Method 1

the gel tends to absorb water from the buffer solution over time. This uptake of water causes swelling of the gel

Methodology Applied
Scientific EffectOsmosis: Osmosis

Implementation Method 2

The comb is also typically made of a material that inhibits polymerization at its surface, thereby preventing the polymerized gel from adhering to the comb

Methodology Applied
Scientific EffectPhotopolymerisation: Photopolymerisation

Data Source

PatentEP2678671B1Dimensional stabilization of slab gel cassettes to prevent distortion caused by swelling gels
Publication Date: 2020.02.19 BIO RAD LABORATORIES INC
  • EP2678671B1 patent drawingFigure 1
  • EP2678671B1 patent drawingFigure 2~3
  • EP2678671B1 patent drawingFigure 4~5

AI summary

Slab gel cassettes for use in electrophoretic analyses of biologically-derived mixtures are equipped with features that prevent the plastic walls of the cassettes from bowing outward when gels retained within the cassettes swell, as gels typically do during casting, storage, or both. In certain embodiments, these features are incorporated into, or mate with, the comb-shaped inserts that form the sample wells as the gels are being cast. In other embodiments, these features are complementary features incorporated into both the comb and the cassette.