Preparing and Maintaining Cogent Diamond Hydride™ Columns

Proper conditioning and storage are essential for optimal performance and longevity of your Diamond Hydride™ HPLC column. Follow these guidelines for first use, routine care, and long-term maintenance.

Initial Conditioning

Before first use:

• Flush the column with 50:50 methanol/DI water for 30 minutes.

Conditioning Based on Sample Type

1. Biological Samples (e.g., urine, plasma):

• Condition: 80% acetonitrile / 20% DI water with 0.2% acetic acid (or 0.1% formic acid) for 20 minutes.
• ​ Clean: After every 10 injections, flush with 50:50 methanol/DI water for 5 minutes.

2. Standard Samples:

• Condition: Same as above (80:20 ACN/DI water with acid) for 20 minutes.
• ​ Clean: After every 100 injections or sooner if performance changes, flush with 50:50 methanol/DI water for 5 minutes.

Storage Guidelines

• Long-Term:

  • Rinse with 10 column volumes of 100% acetonitrile.
  • ​ Cap ends securely and store at room temperature.

• Moderate-Term:

  • Rinse with 6 column volumes of 90:10 acetonitrile/DI water with 0.1% formic or acetic acid.
  • ​ Cap ends and store at room temperature.

Washing to Remove Adsorbed Compounds

• Routine Wash:

  • Use 50:50 methanol/DI water with 0.1% formic acid for 60 minutes at a slower flow rate than normal runs.
  • ​ Re-equilibrate with your mobile phase.

• Deep Cleaning:

  • Wash overnight with 50:50 isopropyl alcohol/DI water with 0.1% formic acid at low flow.
  • ​ If needed, uninstall the column, reverse it, and wash with 50:50 methanol/DI water with 0.1% formic acid for 60 minutes.

Never let the column dry out.