Catalog Number - 68518-15P

The 68518‑15P Cogent RP C18 HPLC Column is designed for high‑resolution analytical separations, featuring 5 µm particles and fully double end‑capped C18 bonding to provide reliable retention, improved peak shape, and consistent performance.

Manufactured using high‑purity silica with traditional octadecylsilane (C18) chemistry, this stationary phase offers:

• Complete end‑capping to minimize silanol interactions

• Improved peak symmetry for polar and basic analytes

• Consistent, reproducible chromatography across methods

This column is widely used as a primary analytical column, a starting point for new method development, and as a USP L1 alternate for 5 µm applications.

150 mm Length – Maximum Resolution & Peak Capacity

• Highest resolving power in the 4.6 mm RP C18 range

• Maximizes peak capacity for complex mixtures

• Ideal for closely related compounds and difficult separations

• Preferred for final method optimization and high‑purity analysis

• Longer run times compared to 50 mm and 100 mm formats

This format is commonly chosen when maximum separation is required and shorter columns do not provide sufficient resolution.

4.6 mm ID – Standard Analytical Performance

• Industry‑standard HPLC column dimension

• Compatible with all conventional HPLC systems

• Typical flow rate range: ~0.8–1.5 mL/min

• Optimal starting range: ~1.0–1.2 mL/min

Provides:

• Strong detector response

• Excellent reproducibility

• Straightforward method transfer between systems

Flow Rate & System Considerations (4.6 mm ID, 5 µm)

• Suitable for conventional HPLC systems

• Supports higher flow rates compared to smaller particle sizes

• Well suited for:

  • Viscous mobile phases

  • Extended gradients

  • Routine and long analytical runs

Why Choose RP C18 (5 µm)

Robust & Reliable Operation

• Ideal for routine analytical workflows

• Lower backpressure relative to smaller particle sizes

• Suitable for long‑lifetime methods and consistent results

Reliable Hydrophobic Retention

• Strong reversed‑phase retention for hydrophobic and neutral compounds

• Excellent for long‑chain fatty acids

• Provides greater retention than C8 phases

Method Development & USP Compatibility

• Ideal for method development and optimization

• Suitable for USP L1 methods using 5 µm particles

• Commonly used as a starting platform for new methods

Cogent RP C18™ Advantages

Fully End‑Capped Surface

• Minimizes secondary interactions

• Improves peak symmetry

• Better performance for basic analytes

High Purity Silica

• Consistent chromatographic performance

• Reduced variability between runs

Durable & Cost‑Efficient

• Long column lifetime

• Reduced system wear

• Lower maintenance frequency

Typical Applications

• Pharmaceutical and QC analysis

• Hydrophobic and neutral compound separations

• Long‑chain fatty acids

• Complex analytical methods

• Method development and validation

• USP L1 reversed‑phase workflows

Important Usage Notes

• Compatible with standard HPLC systems

• Ideal for maximum‑resolution analytical workflows

• Best suited when complex separations require high peak capacity

• Optimize method conditions to balance resolution and run time