1. Faster and More Reliable Equilibration

Conventional HILIC columns rely on the formation and stabilization of a water‑rich partition layer, which typically requires extended equilibration—often 5 minutes per 5 cm of column length, plus additional stabilization time between runs.

TYPE‑C™ HILIC methods equilibrate rapidly, with full equilibration typically achieved in ~7 minutes total, even on comparable column lengths. This rapid equilibration reduces cycle time, improves throughput, and significantly enhances run‑to‑run reproducibility.

2. Reduced Salt Requirements and Cleaner LC‑MS Performance

Many traditional HILIC methods require elevated buffer or salt concentrations to achieve retention of highly polar analytes. This can:

• Increase mobile‑phase preparation complexity
• Contaminate ESI sources
• Suppress ionization efficiency
• Increase baseline noise and maintenance frequency

TYPE‑C™ improved HILIC methods typically achieve strong retention using lower buffer concentrations, improving MS sensitivity while maintaining a cleaner, more stable system.

3. Exceptional Retention‑Time Precision

Retention time drift in conventional HILIC can result from:

• Variability in the water‑rich partition layer
• Long and incomplete re‑equilibration
• Sensitivity to minor changes in salt concentration

In contrast, TYPE‑C™ HILIC retention is governed by stable, surface‑controlled interactions at the silica hydride interface, producing highly repeatable and predictable retention times.

4. Strong Retention at Higher Aqueous Content

Traditional HILIC columns often lose retention as aqueous content increases, limiting gradient flexibility and method robustness.

TYPE‑C™ HILIC maintains strong retention even at elevated water levels, allowing analysts to:

• Retain extremely polar analytes
• Use broader, more forgiving gradients
• Adjust mobile‑phase composition without losing selectivity

This flexibility makes TYPE‑C™ particularly effective for complex mixtures and method development.

5. Extended Column Lifetime and Long‑Term Stability

Conventional HILIC phases may suffer from:

• Silica dissolution
• Salt accumulation
• Gradual disruption of the partition layer

Cogent TYPE‑C™ silica hydride columns demonstrate exceptional stability, frequently delivering up to 10× longer operational lifetimes under demanding LC‑MS and gradient conditions.

6. Compatibility with Conventional RP‑Style Mobile Phases

Unlike traditional HILIC methods that often require dedicated solvent systems, TYPE‑C™ improved HILIC uses standard reversed‑phase mobile phases, typically:

• Water / acetonitrile
• Acid modifiers (e.g., formic or acetic acid)

This simplifies:

• Method development
• Solvent inventory
• Instrument flushing
• Multi‑mode workflows

7. Dual‑Mode HILIC and Reversed‑Phase Retention on a Single Column

TYPE‑C™ columns uniquely support both HILIC‑type and reversed‑phase retention mechanisms:

• HILIC‑type retention under high‑organic conditions
• Reversed‑phase retention under higher‑aqueous conditions

This enables:

• Orthogonal selectivity on one column
• Separation of mixed‑polarity compounds in a single method
• Reduced column changes and simplified screening

This dual‑mode capability is demonstrated in separations of polar analytes (e.g., metformin) and non‑polar compounds (e.g., glyburide) within the same run.
 

Recommended Starting Method for TYPE‑C™ HILIC and RP Evaluation

Note: TYPE‑C™ columns may exhibit HILIC‑dominant or RP‑dominant behavior depending on mobile‑phase composition, making them ideal tools for comparative method optimization.

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Selecting the Optimal TYPE‑C™ Phase for Improved HILIC Applications