Catalog Number - 68318-PG1

The 68318‑PG1 Cogent RP C18 Guard Column Cartridges are designed to extend the life of narrow‑bore analytical and LC‑MS columns, providing highly efficient protection against particulates, strongly retained compounds, and sample matrix fouling in low‑flow applications.

Packed with 3 µm Cogent RP C18™ stationary phase and manufactured using high‑purity silica with traditional octadecylsilane (C18) bonding, these cartridges are fully double end‑capped to provide:

• Reduced silanol interactions

• Improved peak symmetry for polar and basic analytes

• High‑efficiency chromatographic protection for narrow‑bore columns

Each cartridge is constructed in a stainless steel body with stainless steel frits, secured with PEEK frit caps to ensure durability and leak‑free operation in precision analytical systems.

Designed for 2.1 mm ID Columns (LC‑MS / Low Flow)

• Optimized for:

  • 2.1 mm ID LC‑MS columns

  • Low‑flow analytical HPLC methods

✅ Maintains system performance at low flow rates (~0.2–0.3 mL/min typical) ✅ Ideal for mass spectrometry and high‑sensitivity workflows

Purpose of Guard Columns

• Protect analytical columns from:

  • Particulate contamination

  • Strongly retained compounds

  • Sample matrix buildup and fouling

• Extend column lifetime

• Maintain retention time stability and peak shape

• Reduce downtime and column replacement costs

3 µm Guard Media – High‑Efficiency Protection

• Matches high‑efficiency analytical and LC‑MS column packings

• Preserves chromatographic performance and resolution

• Ideal for sensitive, high‑performance applications

✅ Ensures minimal impact on efficiency while maximizing protection

Why Choose RP C18 Guard Cartridges (3 µm, 2.1 mm)

Matched Analytical Chemistry

• Same C18 stationary phase as analytical columns

• Maintains method selectivity and chromatographic integrity

• Prevents system variability

LC‑MS Workflow Protection

• Protects columns used in low‑flow, high‑sensitivity assays

• Reduces contamination reaching the MS detector

• Critical for trace‑level analysis

Reduced System Downtime

• Minimizes need for frequent column replacement

• Supports high‑throughput analytical labs

Cogent RP C18™ Advantages

Fully End‑Capped Surface

• Minimizes secondary interactions

• Improves peak symmetry

• Enhances reproducibility

High Purity Silica

• Consistent performance across injections

• Reliable guard‑to‑guard reproducibility

Precision Construction

• Stainless steel cartridge body and frits

• PEEK sealing components

• Built for low‑flow analytical system compatibility

Important Usage Notes

• ⚠️ Must be used with a compatible guard column holder system

• Designed specifically for 2.1 mm ID LC‑MS and low‑flow HPLC systems

• Replace regularly to maintain optimal performance and protection

• Essential for protecting high‑value analytical columns