Supel-Connect HPLC Fittings

How They Work

Problem: HPLC systems are forced to their pressure limits under fast HPLC and high resolution HPLC conditions. System back pressure issues can arise from efforts to increase efficiency and resolution; such as, increasing flow rates and column lengths, as well as reducing particle size. PEEK is the traditional tubing material of choice for most applications, but it is no longer suitable for high performance HPLC.  The PEEK tubing can slip or become distorted under high pressures, causing poor resolution, diminished efficiency and system failures. High performance HPLC requires a more advanced type of fitting; one which can handle the higher pressures without fail, while still eliminating dead volume that contributes to band broadening and decreased resolution.

Solution: Supelco® has developed a line of high performance fittings that maintain the integrity of your HPLC systems up to 15,000 psi with mere finger tightening! The Supel-Connect High Performance Fittings and Interconnects are made of 316 Stainless Steel and use a sliding ferrule design to allow for installation into any port.  The design allows the user two degrees of freedom in compressing the ferrule. Partial separation of radial and axial tightening forces allow the fitting to withstand pressures greater than 15,000 psi, while providing superior elimination of dead volume.  Figure 1 shows the HPLC column efficiency as a function of system backpressure. The system equipped with PEEK fittings illustrates gradual loss of efficiency starting at 3,000 psi with an eventual catastrophic failure at 5,500 psi. The Supelco High Performance Fittings show no performance loss as a function of pressure.


Supelco High Performance Fittings versus Standard PEEK Fittings

Figure 1. Supelco High Performance Fittings versus Standard PEEK Fittings

High performance interconnects can be used on most HPLC systems.  They are available in various configurations, with either flexible or rigid stainless tubing.  With the right configuration of fittings and nuts, they can also be used with PEEK, PEEKsil™, or stainless steel tubing of your choice to extend the pressures limits of standard tubing.  For more information and to see a video demonstrating the Supel-Connect high performance fittings, visit




Supel is a trademark of Sigma-Aldrich Co. LLC
PEEKSil is a trademark of SGE International Pty Ltd.
Supelco is a registered trademark of Sigma-Aldrich Co. LLC

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