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High-throughput and Comprehensive Drug Surveillance Using Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry
Published on: April 23, 2019
Coupling CE with atmospheric pressure photoionization MS for pharmaceutical basic compounds: optimization of
Julie Schappler1, Davy Guillarme, Josiane Prat
1Laboratory of Analytical Pharmaceutical Chemistry, School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne, Geneva, Switzerland.
Electrophoresis
|August 29, 2007
Summary
This study optimizes atmospheric pressure photoionization (APPI) for capillary electrophoresis-mass spectrometry (CE-MS) analysis. Experimental design successfully enhanced sensitivity for charged species detection in small sample volumes.
Area of Science:
- Analytical Chemistry
- Separation Science
- Mass Spectrometry
Background:
- Capillary electrophoresis coupled with mass spectrometry (CE-MS) is vital for analyzing charged species.
- Electrospray ionization (ESI) is the standard interface for CE-MS due to its ease of use and sensitivity.
- Atmospheric pressure photoionization (APPI) offers an alternative but requires extensive parameter optimization for CE coupling.
Purpose of the Study:
- To systematically optimize APPI source parameters for enhanced CE-MS sensitivity.
- To evaluate the effectiveness of experimental design methodologies in optimizing complex analytical interfaces.
- To achieve high signal-to-noise ratios for sensitive detection of analytes.
Main Methods:
- Utilized a fractional factorial design (FFD) to screen critical APPI source parameters.
- Employed a face-centered central composite design (CCD) for predicting and optimizing sensitivity.
- Evaluated parameters including sheath liquid flow rate, drying gas conditions, nebulizing gas pressure, vaporizer temperature, and capillary voltage.
Main Results:
- Identified key factors significantly influencing CE-MS sensitivity and efficiency using FFD.
- Successfully optimized APPI source parameters through CCD, leading to improved analytical performance.
- Achieved height-to-noise ratios (H/N) of approximately 10 for analytes at 200 ng/mL concentrations.
Conclusions:
- Experimental design methodologies are effective for optimizing APPI-CE-MS interfaces.
- Optimized APPI-CE-MS provides a sensitive and robust method for analyzing charged species.
- This work advances the application of APPI as a viable alternative to ESI for CE-MS.
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