ABSTRACT
Liquid chromatography (LC) and high-performance LC (HPLC) will be used as equivalent terms in this chapter. The results obtained from any liquid chromatographic system are dependent on and limited by the performance of all independent system components. A primary concern of the chromatographer is to prevent the sample from spreading owing to factors other than the column separation mechanism as it travels through the chromatograph. A properly designed injection valve, operated in the correct manner, ensures that the sample begins the separation process as a narrow band. Without proper injection, optimum chromatographic performance can never be achieved.
