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Published on: January 7, 2019
Fused-core particles: a practical alternative to sub-2 micron particles
1Analytical Research and Development, Pfizer Global Research and Development, Groton/New London Laboratories, Eastern Point Road, Groton, CT 06340, USA. john.j.salisbury@pfizer.com
Journal of Chromatographic Science
|November 15, 2008
Summary
Fused-core columns offer a practical alternative for pharmaceutical chemists, providing high efficiency at conventional High-Performance Liquid Chromatography (HPLC) pressures. These columns demonstrate excellent performance and robustness for analyzing drug impurities.
Area of Science:
- Analytical Chemistry
- Chromatography
Background:
- Sub-2 micron particle size columns enhance Ultra-High-Performance Liquid Chromatography (UHPLC) efficiency and throughput.
- UHPLC instrumentation may not be accessible to all pharmaceutical chemists.
- Fused-core particles present a viable alternative, operating at conventional HPLC pressures.
Purpose of the Study:
- To evaluate the efficiency and robustness of fused-core columns.
- To analyze a mixture of Torcetrapib and its related impurities.
- To compare fused-core column performance against established UHPLC particles.
Main Methods:
- Utilized fused-core columns (2.7 µm particle size) for chromatographic separations.
- Analyzed a mixture of Torcetrapib and impurities.
- Assessed column efficiency (theoretical plates), backpressure, and robustness over 500 injections.
Main Results:
- Achieved high theoretical plates (approx. 14,000) with run times under 5 minutes.
- Fused-core columns provided 80% of the efficiency of sub-2 micron particles at half the backpressure.
- Demonstrated excellent reproducibility with relative standard deviations <1% for key chromatographic parameters.
Conclusions:
- Fused-core columns offer a practical and efficient alternative for pharmaceutical analysis.
- These columns provide a balance of high performance and lower operational pressure.
- The robustness of fused-core columns supports their use in routine pharmaceutical quality control.
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