Catalog Number - 68518-P21-250

The 68518‑P21‑250 Cogent RP C18 Preparative HPLC Column is engineered for maximum separation performance in high‑capacity purification workflows, utilizing 5 µm particles and fully double end‑capped C18 bonding to deliver reliable retention, 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 purification performance

This column is ideal as a USP L1 alternate and as a high‑resolution platform for preparative purification and production‑scale workflows.

250 mm Length – Maximum Separation & Highest Purity

• Highest resolving power in the 21.2 mm RP C18 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 purification and highest‑purity isolation

This configuration is selected when shorter columns cannot achieve required resolution or purity.

21.2 mm ID – High‑Capacity Preparative Scale

• Provides very high sample loading capacity

• Designed for large‑scale purification and batch processing

• Supports high‑flow preparative chromatography workflows

Typical Flow Rate Range

• ~10–30 mL/min (system dependent)

• Optimize based on instrument capability and purification goals

✅ Designed for preparative HPLC systems capable of high flow rates and large injection volumes

Flow Rate & System Considerations (21.2 mm ID, 5 µm)

• Requires systems capable of:

  • High flow rates

  • Large injection volumes

• Compatible with:

  • Preparative pumps

  • High‑volume injection systems

  • Fraction collection systems

⚠️ Not intended for analytical or semi‑prep HPLC systems

Why Choose RP C18 (5 µm, Preparative Scale)

Maximum Resolution for Final Purification

• Ideal for final purification of complex mixtures

• Maximizes separation efficiency and product purity

• Supports high‑purity isolation 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 for regulated and validated environments

• Supports method transfer across scales

Cogent RP C18™ Advantages

Fully End‑Capped Surface

• Minimizes secondary interactions

• Improves peak symmetry

• Enhances performance for challenging analytes

High Purity Silica

• Consistent chromatographic performance

• Reduced variability between batches

Durable & Cost‑Efficient

• Long column lifetime

• Designed for high‑load purification cycles

• Reduced maintenance requirements

Typical Applications

• Preparative purification

• High‑purity compound isolation

• Complex mixture separations

• Pharmaceutical and QC workflows

• Pilot‑scale to production purification

• USP L1 reversed‑phase methods

Important Usage Notes

• Designed for preparative HPLC systems (21.2 mm ID)

• Requires high‑flow capability and large sample loading capacity

• Ideal for maximum‑resolution purification workflows

• Optimize conditions for resolution vs throughput balance

Made‑to‑Order & Pricing Information

This is a custom, made‑to‑order item.

• Orders cannot be canceled once placed

• Custom items are non‑returnable

• Please contact Customer Service for formal quotation, lead time, and ordering assistance. Classification:

• This item is classified as a CUSTOM ITEM. View our Custom Item policy.