Catalog Number - 68018-25P

The 68018‑25P Cogent RP C18 HPLC Column is designed for maximum separation performance and method compatibility, utilizing 10 µm particles and fully double end‑capped C18 bonding to provide reliable retention, excellent durability, and consistent chromatographic results.

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

• Complete end‑capping to minimize silanol interactions

• Improved peak symmetry for polar and basic analytes

• Consistent and reproducible chromatography

This column is widely used as a USP L1 alternate and is especially valuable for legacy methods that specify longer column formats.

250 mm Length – Maximum Separation & Peak Capacity

• Highest resolving power in the 4.6 mm RP C18 (10 µm) range

• Maximizes peak capacity for highly complex mixtures

• Ideal for closely related compounds and difficult separations

• Provides extended retention for hydrophobic analytes

• Best suited for final method validation and high‑purity separations

This format is selected when shorter columns cannot achieve the required separation performance.

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

• Reliable reproducibility

• Easy method transfer across laboratories

Flow Rate & System Considerations (4.6 mm ID, 10 µm)

• Suitable for standard HPLC systems

• Supports higher flow rates and increased loading capacity

• Well suited for:

  • Legacy analytical methods

  • Method validation workflows

  • Complex, extended separations

Why Choose RP C18 (10 µm)

Ideal for Legacy & Preparative Method Alignment

• Commonly used in older validated methods still in use today

• Maintains method conformity without revalidation

• Suitable for analytical-to-preparative method scaling workflows

Reliable Hydrophobic Retention

• Strong reversed‑phase retention for hydrophobic and neutral compounds

• Excellent for long‑chain fatty acids

• Provides greater retention than C8 phases

USP Method Compatibility

• Suitable for USP L1 methods

• Reliable alternate column for regulated environments

• Supports method transfer and validation consistency

Cogent RP C18™ Advantages

Fully End‑Capped Surface

• Minimizes secondary interactions

• Improves peak symmetry

• Enhances performance for basic analytes

High Purity Silica

• Consistent chromatographic performance

• Reduced variability between runs

Durable & Cost‑Efficient

• Long column lifetime

• Ideal for validated and repeat workflows

• Reduced maintenance frequency

Typical Applications

• Legacy USP L1 method replacement

• Pharmaceutical QC and validation

• Hydrophobic and neutral compound separations

• Long‑chain fatty acids

• Complex multi‑component mixtures

• Regulatory and method transfer workflows

Important Usage Notes

• Compatible with standard HPLC systems

• Ideal for maximum separation and legacy method replication

• Use when method fidelity and reproducibility are critical

• Optimize conditions to balance run time and resolution