The LC Column Playbook

Importance of the Topic

Ultra-high performance liquid chromatography relies on column efficiency, selectivity and retention to achieve baseline separations. Core-shell Poroshell 120 particles deliver high plate counts at moderate pressures, making them essential for rapid, high-resolution analyses in pharmaceutical, environmental, food and biochemical laboratories.

Study Objectives and Overview

This guide presents strategies to optimize chromatographic resolution by balancing efficiency (plate number), selectivity (bonded phase and mobile phase) and retention (k-values). It compares Poroshell 120 columns of various particle sizes and bonded phases in reversed-phase and HILIC modes, demonstrating their performance across applications such as antioxidants, beta-blockers, NSAIDs, vitamins, sugars, amino acids, inorganic ions and polar pesticides.

Methodology and Instrumentation

• Columns: Poroshell 120 EC-C18, SB-C18, HPH-C18, Phenyl-Hexyl, Bonus-RP, SB-Aq, EC-CN, PFP, HILIC-Z, HILIC-OH5
• Particle sizes: 1.9 µm, 2.7 µm, 4 µm; lengths: 50 mm–150 mm; IDs: 2.1 mm, 3.0 mm, 4.6 mm
• Mobile phases: water, acetonitrile, methanol, buffers (ammonium formate/acetate), pH 1–12 for RP; ACN/water with buffer for HILIC
• Detection: diode array (UV at 240–260 nm), triple-quadrupole MS/MS, evaporative light scattering (ELSD)
• Systems: standard LC and UHPLC platforms, pressure ratings up to 1,300 bar

Key Results and Discussion

• Resolution equation highlights selectivity as the dominant factor; efficiency increases with column length and smaller particle size (√N dependence), while retention contributes at low k values.
• Comparisons show 1.9 µm Poroshell columns achieving sharper, narrower peaks and higher resolution (Rs ≈ 2.2) at moderate backpressures (~226 bar) versus 2.7 µm and 4 µm.
• Bonded-phase variants provide tailored selectivity: reversed-phase phases resolve beta-blockers, NSAIDs and antioxidants; HILIC phases excel at polar pesticides, amino acids and sugars.
• HILIC modes offer fast re-equilibration (~1.5 min), excellent reproducibility over thousands of column volumes, and improved MS sensitivity for polar analytes.
• Case studies illustrate separation of water-soluble vitamins, inorganic ions and high-pH sugar analysis with robust peak shape and long column lifetime.

Benefits and Practical Applications

• Poroshell technology merges UHPLC speed with reduced backpressure compared to fully porous sub-2 µm particles, enhancing laboratory throughput.
• Wide pH stability (1–12) enables flexible method development for acidic and basic compounds.
• Multiple bonded phases on the same core-shell particle simplify selectivity screening and method optimization.
• HILIC phases extend reversed-phase capabilities to strongly polar analytes, compatible with MS in both ionization modes.
• Applications in quality control, research and industrial analytics benefit from high resolution, sensitivity and robustness.

Future Trends and Applications

Emerging core-shell and mixed-mode stationary phases will further boost resolution under ultra-high pressures. Integration with high-resolution mass spectrometry and automated method scouting will accelerate development. Advanced polar separation techniques and tailored chemistries are expected to expand capabilities for challenging analytes, biomolecules and real-time monitoring.

Conclusion

The Poroshell 120 platform, with its versatile particle sizes and diverse bonded phases including HILIC, offers a powerful approach to maximize chromatographic resolution by strategically tuning efficiency, selectivity and retention. This technology supports robust, high-throughput analyses across a wide range of chemical classes while maintaining manageable system pressures and simplified method development.