Replaceable Electrospray Emitter Assembly for Reproducible Nano LC-MS Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current electrospray emitter systems for mass spectrometry face challenges such as ion loss, increased dead volume leading to reduced detection sensitivity, and difficulties in achieving reproducible connections between separation columns and mass spectrometers, particularly at low flow rates, which affects chromatographic separation and detection sensitivity.
Innovation Solution
A low dead volume replaceable electrospray emitter assembly with a capillary having an inlet and outlet end, integrated stop with a through hole for liquid flow, and a retractable protective sleeve for easy connection and protection, allowing for efficient interfacing with a broad range of flow rates, including nano LC-MS applications.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional ESI interfaces with multiple connections and transfer lines are used to connect the column and emitter, then the connection reliability is improved, but the dead volume increases leading to reduced detection sensitivity
Solution Approach 1:
The patent integrates the emitter assembly with the separation column by directly coupling the emitter to the column outlet, eliminating multiple transfer lines and connections. This merging of components reduces dead volume while maintaining reliable liquid flow from the column to the emitter through a single integrated pathway.
Solution Approach 2:
The emitter assembly is designed as a replaceable module that can be independently exchanged. This segmentation allows the emitter to be optimized for low dead volume connections while the rest of the system remains modular, enabling reliable connections without requiring multiple transfer lines throughout the entire system.
2Measurement precision
If small inner diameter columns are used to reduce dead volume and improve sensitivity, then the detection sensitivity is improved, but the operating flow rate decreases requiring more precise connection control
Solution Approach 1:
The emitter assembly incorporates self-aligning features including a conical interface that automatically centers the emitter with the column outlet during insertion. This self-service mechanism eliminates the need for manual alignment, ensuring precise connections even with small inner diameter columns while maintaining ease of operation.
Solution Approach 2:
A conical alignment feature acts as an intermediary element between the emitter and column outlet. This mediator guides the emitter into precise alignment during insertion, ensuring accurate positioning without requiring manual adjustment, thereby facilitating precise connections for small bore columns.
3Adaptability or versatility
If users manually assemble the nano spray emitter with the nano LC column using sleeves and fittings, then the adaptability is improved, but the manufacturing precision and reproducibility decrease due to improper connections
Solution Approach 1:
The emitter and column outlet are merged into a single integrated assembly with a unified interface. This eliminates the need for separate sleeves and fittings that require manual assembly, thereby maintaining adaptability while ensuring consistent manufacturing precision through factory-prepared integrated connections.
Solution Approach 2:
The emitter assembly is designed as a disposable or replaceable unit that is pre-assembled with precision connections. This approach sacrifices the reusability of individual components but ensures high manufacturing precision and reproducibility, as each new emitter assembly comes pre-configured with accurate connections from the manufacturer.
4Volume of stationary object
If the emitter is directly attached to the nano column outlet using a union, then the dead volume is minimized, but the ease of repair and replacement decreases
Solution Approach 1:
The system is segmented into a permanent union attached to the column and a replaceable emitter assembly. This segmentation maintains the low dead volume benefit of direct attachment while enabling easy replacement of the emitter by simply detaching and reattaching the modular assembly through the union interface.
Solution Approach 2:
The connection interface is designed with dynamic characteristics allowing for quick attachment and detachment. The union provides a stable, low dead volume connection when assembled, while enabling rapid replacement of the emitter assembly when needed, thus adapting between stability and ease of repair based on operational requirements.
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 improved chromatographic separation and detection sensitivity by minimizing dead volume, ensuring reliable connections, and enabling easy replacement of the emitter assembly, thus enhancing the reproducibility and performance of mass spectrometry analyses.
Implementation Method 1
Electrospray ionization (ESI) is a technique to produce gas phase ions from liquid solution while applying a high voltage to create aerosol
Implementation Method 2
A stop with a defined through hole is integrated proximate the inlet end of the emitter to produce a path for liquid to flow from the separation column to the emitter via the through hole
Data Source
AI summary
An electrospray emitter assembly for interfacing a separation column to a mass spectrometer is disclosed. An emitter capillary includes an inlet end and an outlet end. A fitting is coupled to the inlet end of the emitter, configured to be removably connected to the separation column. A stop with a defined through hole is integrated proximate the inlet end of the emitter to produce a path for liquid to flow from the separation column to the emitter via the through hole where a voltage is applied to the liquid entering the emitter.