LC Automation

Abstract

The aims of this article are to describe and illustrate the many types of integrated processes that are performed online with liquid chromatography (LC) to achieve sample preparation and to highlight applications that demonstrate their value. Most often, these processes will be interfaced with LC in an unattended manner to free analyst hands-on time, thus improving productivity. In the simplest case, a single filtration cartridge is employed to accomplish automated sample cleanup prior to injection, while for more complex assays, multiple extraction and separation columns placed in-line with the chromatographic system are synced with the detection system in a manner described as multidimensional. Careful synchronization in this manner is facilitated by advanced software that closely monitors and controls valves, liquid flow, and hardware options via a seamless interface. The processes to be discussed are all considered online techniques, that is, the actions are performed in tandem with the liquid chromatographic separation in an unattended manner. Those processes that prepare the sample and are performed immediately before loading onto the analytical separation column constitute the majority of techniques; however, postanalytical column automated processes (e.g., postcolumn derivatization) also exist and are performed following analytical separation but immediately before detection.