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A High Performance Impedance-based Platform for Evaporation Rate Detection
Published on: October 17, 2016
Improving the universal response of evaporative light scattering detection by mobile phase compensation
André de Villiers1, Tadeusz Górecki, Frédéric Lynen
1Pfizer Analytical Research Centre, Ghent University, Krijgslaan 281 S4-bis, B-9000 Ghent, Belgium.
Journal of Chromatography. A
|June 15, 2007
Summary
Mobile phase compensation effectively eliminates mobile phase-dependent response in evaporative light scattering detectors (ELSD). This technique ensures a stable ELSD response, enabling accurate analysis of sulfonamide drugs using gradient Ultra-Performance Liquid Chromatography (UPLC).
Area of Science:
- Analytical Chemistry
- Chromatography
Background:
- Evaporative light scattering detectors (ELSD) exhibit mobile phase-dependent responses, complicating quantitative analysis.
- Mobile phase composition significantly impacts ELSD response factors, leading to variability in drug analysis.
- Charged aerosol detector (CAD) mobile phase compensation is a known technique to address detector response variability.
Purpose of the Study:
- To adapt and apply mobile phase compensation to evaporative light scattering detectors (ELSD).
- To overcome mobile phase-dependent response issues in ELSD for improved analytical accuracy.
- To demonstrate the efficacy of mobile phase compensation in gradient Ultra-Performance Liquid Chromatography (UPLC) separations.
Main Methods:
- Implementation of mobile phase compensation using a secondary pump with a reversed gradient.
- Flow injection analysis and gradient elution modes were employed to test the compensation technique.
- Analysis of six sulfonamide drugs with and without mobile phase compensation.
Main Results:
- Mobile phase compensation effectively eliminated a two-fold difference in ELSD response factors caused by varying mobile phase composition (10-90% acetonitrile).
- With compensation, the ELSD demonstrated a nearly constant response, indicating concentration-sensitive behavior.
- Successful gradient UPLC-ELSD separation and analysis of sulfonamide drugs at the 0.05% level were achieved with mobile phase compensation.
Conclusions:
- Mobile phase compensation is a viable and effective method for stabilizing ELSD response.
- The technique significantly improves the reliability of quantitative analysis using ELSD, especially in gradient chromatography.
- This approach enables accurate determination of analytes like sulfonamide drugs under varying mobile phase conditions.
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