Three Reasons You’ll Want to Switch to Agilent Capillary Tubing

Stainless steel tubing is the industry standard for HPLC and UHPLC systems due to its exceptional strength, solvent compatibility, and ability to withstand extremely high pressures. In contrast, PEEK tubing (polyether ether ketone) is a popular biocompatible alternative prized for its flexibility and ease of use—it can be cut to length directly in the lab without specialized tools. No matter which material you choose, the right tubing length, internal diameter (ID), and connections are key to maintaining system efficiency, peak integrity, and reproducible chromatographic performance.

Should You Use Stainless Steel or PEEK Tubing?

Stainless steel tubing remains the preferred choice for most standard HPLC and UHPLC applications because it offers unmatched pressure tolerance and chemical compatibility. However, in cases where bio-inertness is required—such as protein, peptide, or biomolecule separations—PEEK tubing (or another bio-inert alternative) is a better fit.

Chrom Tech recommends Agilent’s 0.6 mm OD flexible stainless steel capillaries from the InfinityLab line. These capillaries offer superior handling and performance compared to conventional rigid 1.6 mm OD tubing, with several standout advantages:

• Preserved Inner Diameter Integrity
  Unlike traditional rigid tubing, these flexible capillaries can be bent, coiled, or twisted—even into a knot—without affecting the inner diameter. This ensures consistent flow and reliable performance, even in compact instrument configurations.

• Hassle-Free Connections
  The flexible stainless steel capillaries are easier to handle and install compared to conventional tubing. They are fully compatible with Agilent InfinityLab Quick Connect fittings, providing secure, leak-free connections without tools—ideal for high-pressure column connections and fast column changes.

• Ultra-High Pressure Performance
  Flexibility does not come at the cost of durability. These capillaries maintain the same UHPLC pressure ratings as standard stainless steel tubing and can withstand ultra-high pressures when used with compatible high-pressure fittings.

For more information, consult Chrom Tech’s capillary selection guide or contact one of our technical product specialists to find the ideal tubing for your application.