The Knauer pulse dampers combine high damping performance with reliable membrane-free assembly and easy implementation into the HPLC system. Especially when working close to the limit of detection, they can significantly improve the detection of trace components by reducing noise of the baseline. This technical note evaluates the high volume Knauer pulse damper and compares it’s performance to that of two competitors’ dampers.
The results of the Technical Note shows that the Knauer pulse damper works with a damping efficiency of 95 % at 680 bar with a flow of 0.5 ml/min. Similarly, the dampers of competitors, denoted as 1 and 2, work with 90 % and 33 % efficiency respectively under these same running conditions.
Figure 1: Comparison of the KNAUER pulse damper (high volume version) with two competitor dampers and a configuration without pulse damper. The pressure trace was recorded with an AZURA P 6.1L pump with water at a flow rate of 0.5 mL/min; dark blue – KNAUER pulse damper, grey – competitor 1, red – competitor 2, light blue – no pulse damper.
The signals with the Knauer pulse dampers reach a full plateau before the end of every gradient step, while the signals with the competitor dampers do not reach the same signal height (Fig.2). These dampers appear to both have areas
with insufficient perfusion and therefore would need a longer gradient program to reach the gradient steps. The Knauer pulse dampers feature a flow path geometry designed for clean flush out and hence show a very effective mixing performance.