HPLC Device / Kholood Yassin

HPLC Device

Written by / Kholood Yassin 

High performance / Pressure liquid chromatography ( HPLC ) : Is a chromatographic technique used to separate the components in a mixture, to identify each component, and to quantify each component. Chromatography can be described as a mass transfer process involving adsorption. HPLC relies on pumps to pass a pressurized liquid and a sample mixture through a column filled with a sorbent, leading to the separation of the sample components. The components of the sample mixture are separated from each other due to their different degrees of interaction with the sorbent particles (Active component of the column, e.g. Silica) which also called Stationary Phase .The pressurized liquid is typically a mixture of solvents called Mobile Phas. The schematic of an HPLC instrument typically includes a sampler, pumps, and a detector. The sampler brings the sample mixture into the mobile phase stream which carries it into the column. The pumps deliver the desired flow and composition of the mobile phase through the column. The detector generates a signal proportional to the amount of sample component emerging from the column, hence allowing for quantitative analysis of the sample components. A digital microprocessor and user software control the HPLC instrument and provide data analysis. The schematic below representation of an HPLC unit: (1) Solvent reservoirs, (2) Solvent degasser, (3) Gradient valve, (4) Mixing vessel for delivery of the mobile phase, (5) High-pressure pump, (6) Switching valve in "inject position", (6') Switching valve in "load position", (7) Sample injection loop, (8) Pre-column (guard column), (9) Analytical column, (10) Detector (i.e. IR, UV), (11) Data acquisition, (12) Waste or fraction collector .