High performance liquid chromatography has proven itself to very useful in many scientific fields, yet forces scientists to consistently choose between speed and resolution. Ultra High Performance Liquid Chromatography (UHPLC) eliminates the need to choose and creates a highly efficient method that is primarily based on small particle separations. 14.1: Scope of Liquid Chromatography 14.2: High-Performance Liquid Chromatography In high-performance liquid chromatography (HPLC) we inject the sample, which is in solution form, into a liquid mobile phase. The mobile phase carries the sample through a packed or capillary column that separates the sample’s components based on their ability to partition between the mobile phase and the stationary phase. this section is largely as is found in Harvey's analytical chemistry but expanded 14.3: Chiral Chromatography This sections was adapted from the PhD thesis of Anita Sztojkov-Ivanov Ph.D. titled HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC SEPARATION OF THE ENANTIOMERS OF AMINO COMPOUNDS ON CHIRAL STATIONARY PHASES Institute of Pharmaceutical Chemistry, University of Szeged 2008 14.4: Ion Chromatography In ion-exchange chromatography (IEC) the stationary phase is a cross-linked polymer resin, usually divinylbenzene cross-linked polystyrene, with covalently attached ionic functional groups. 14.5: Size-Exclusion Chromatography Size exclusion chromatography is a technique that separates compounds solely on the basis of size. In order for the results of size exclusion separations to be meaningful, there can be no directed forces between the compounds being separated and the surface of the particles used as the stationary phase. Instead, the particles are prepared with well-characterized pore sizes. 14.6: Thin-Layer Chromatography Thin layer chromatography is done exactly as it says - using a thin, uniform layer of silica gel or alumina coated onto a piece of glass, metal or rigid plastic. The silica gel (or the alumina) is the stationary phase. The stationary phase for thin layer chromatography also often contains a substance which fluoresces in UV light - for reasons you will see later. The mobile phase is a suitable liquid solvent or mixture of solvents. 14.7: Problems End-of-chapter problems to test your understanding of topics covered in this chapter. "File:High-performance liquid chromatography.jpg" by Dqwyy is licensed under CC BY-SA 4.0