The aim of this unit is to describe the role of the solvent delivery system (pump) within high pressure liquid chromatography (HPLC). The operational principles of the most popular solvent delivery types are explained, as well as the function of the components and potential troubleshooting and maintenance issues. We will describe good practice in pump use, care and storage, and discuss the operating principle of alternative pump designs such as preparative and micro-flow pumping systems.

At the end of this module you will be able to explain the working principles of the most popular solvent delivery systems in HPLC; demonstrate knowledge of the working principles of various solvent delivery system components and explain maintenance procedures; describe the advantages of dual piston pumps over single piston pumps; recognize system problems from characteristic baseline problems; and identify solvent delivery system problems associated with retention time variation.

Topics include: 

• Simple pumping systems
• Disadvantages of single piston pumps
• Dual piston reciprocating pumps
• Accumulator pumps
• Binary pumps
• Quaternary pumps
• Ternary pumps
• Check valves
• Pistons
• Seal wash
• Pulse dampers
• Purge valves
• Flushing gradients
• System dwell volume and time
• Troubleshooting - high back pressure
• Troubleshooting - check valves and pistons
• Troubleshooting - solvent mixing issues
• Preparative pumps
• Capillary (low volume) pumping systems
• Calibration and testing