Sigma-Aldrich Guide #
The pump must deliver a constant flow of solvent to the column over a wide range of conditions. HPLC pumps incorporate single or dual piston, syringe, or diaphragm pump designs.
Pumping system problems are usually easy to spot and correct. Some of the more common symptoms are erratic retention times, noisy baselines, or spikes in the chromatogram. Leaks at pump fittings or seals will result in poor chromatography. A sure sign of a leak is a buildup of salts at a pump connection. Buffer salts should be flushed from the system daily with fresh deionized water. To isolate and repair specific problems related to your apparatus, use the troubleshooting and maintenance sections of the operation manual. Pump seals require periodic replacement. You should perform regular maintenance rather than waiting for a problem to occur.