chemistry

HPLC chromatography: The five major hplc components The five major HPLC components and their functions In a previous post entitled “ What is Liquid Chromatography? What is HPLC (High Performance Liquid Chromatography ) ” the LC and the HPLC analytical techniques were introduced and the main advantages and disadvantages were explained. The five major HPLC components and their functions are going to be presented in this post:   The Pump : The role of the pump is to propel (force) a liquid (the mobile phase) through the chromatograph at a specific flow rate , expressed in ml/min. Normal flow rates in HPLC are 1-2 ml/min and typical pumps can reach pressures in the range of 2000 – 9000 psi but in applications covered under UHPLC mode operating pressure can be as high as 15000-18000 psi. The normal flow rate stability must be < 1%.   An ideal pump should have the following characteristics: Solvent compa

What is Liquid Chromatography (LC)? What is HPLC (High Performance Liquid Chromatography)? HPLC / Liquid Chromatography (LC) History Historically, chromatography dates back to a Russian chemist, Mikhail Tswett , who gave a lecture in 1903 on the separation of the pigments in green leaves on a chalk column. His first papers were actually published in 1906. Another researcher, David Talbot Day , an American, was simultaneously using chromatography in his work on the separation of hydrocarbons from petroleum. Tswett, however generally receives all the credit because he was able to recognize and   understand the chromatographic process .  Tswett filled an open glass column with particles of powdered chalk (calcium carbonate) and alumina. He poured a sample (solvent extract of plant l