Fluidic Coupling Seal Endface Design for UPLC Carryover Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fluidic couplings used in high-pressure chemical analysis systems, such as UPLC, suffer from issues like carryover and peak tailing due to unswept volumes and corrosion, which degrade chromatographic measurements and require costly replacement when leaks occur.
Innovation Solution
A polymeric fluidic coupling seal with a deformable design that absorbs compression without obstructing the fluid channel, using a polyimide-based material that flows into a deformation volume to prevent fluid channel collapse and eliminate unswept volumes, allowing for easy assembly and repeated use.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional compression fitting with an annular sealing element is used to achieve fluid-tight seal, then sealing reliability is improved, but unswept volume is created leading to carryover and peak tailing
Solution Approach 1:
Instead of forming the seal at the side of the capillary as in conventional fittings, this invention inverts the sealing approach by forming the seal at the endface of the capillary. The planar sealing surface is located at the end of the receptacle, directly contacting the endface of the inserted capillary, thereby eliminating the unswept volume that causes carryover and peak tailing while maintaining sealing reliability.
2Reliability
If compression force is applied to achieve contact seal between annular sealing element and capillary, then sealing reliability is improved, but corrosion occurs at the capillary interface
Solution Approach 1:
This invention extracts the sealing function from the side interface of the capillary and relocates it to the endface of the capillary. By moving the sealing contact point from the lateral surface to the endface, the design eliminates the corrosion-prone side interface while maintaining effective sealing through the planar contact at the endface.
3Measurement precision
If a polymeric coupling seal with deformable design is used to eliminate unswept volume, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The coupling seal utilizes parameter changes in the polymeric material, specifically its deformability and flow characteristics. The polymeric body is designed to deform and flow into the deformation volume under compression, allowing it to adapt to manufacturing tolerances and assembly variations while maintaining the planar sealing surface contact at the capillary endface, thus achieving precise sealing without complex mechanical structures.
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 reduces carryover and corrosion, maintains fluid integrity, and allows for easy replacement and reuse of the coupling seal, improving chromatographic measurement accuracy and reducing maintenance costs.
Implementation Method 1
A void between an outer surface of the polymeric body and an inner surface of the coupling body acts as a deformation volume that accepts the deformation of the coupling seal while under compression
Implementation Method 2
The coupling seal includes a polymeric body... A void between an outer surface of the polymeric body and an inner surface of the coupling body acts as a deformation volume that accepts the deformation of the coupling seal while under compression
Data Source
Figure 1~2B
Figure 2A
Figure 3A
AI summary
Described is a coupling seal that includes a polymeric body having a bore extending from a first end to an internal sealing surface and a fluid channel extending from the internal sealing surface to a second end. The bore is configured to receive a tube having a fluid channel so that an endface of the tube engages the internal sealing surface. The second end of the polymeric body is configured to contact a sealing surface of a coupling body that has a fluid channel extending from the sealing surface. A fluidic seal occurs when the coupling seal is compressed between the endface and the sealing surface. A void between an outer surface of the polymeric body and an inner surface of the coupling body receives the deformation of the coupling seal while under compression to thereby prevent the fluid channel of the tube from being crushed or obstructed.