|
|||||||
|
|
|
|
||||
|
|
|||||||
HPLC (High Performance Liquid Chromatography)
HPLC (High Performance Liquid Chromatography) is the technique that involves separation of compounds based on the difference in their interactions with column packing. A sample is carried by a moving or mobile phase (eluent) past a stationary phase in a column. The sample components migrate through the column only when they are in the mobile phase. The velocity of migration of a component in the sample is a function of the equilibrium distribution of component between the mobile phase and the stationary phase. The components having distributions favoring the stationary phase migrate slower than those having distributions favoring the mobile phase. The separated components are detected when they exit the column. At NDE, detection may be performed using a UV / visible photodiode array, a refrative index detector, or a fluorescence detector.