Varian HPLC
Image source: courtesy R. Johnson
Image source: courtesy R. Johnson
High Performance Liquid Chromatography (HPLC)
Like gas chromatography, high performance liquid chromatography (HPLC) is a method to separate and measure chemical analytes. A column (~ 5 mm internal diameter; 10 - 20 cm length) contains a stationary phase of small particulates; the mobile phase is a liquid that is pumped through the column at high pressure (200 bar) (see Ch. 5 in Fifield and Haines, 2000).
- The mobile phase must be purged of dissolved gases
- Pumps must be capable of high pressure and steady flow
Detectors
After leaving a column, the mobile phase passes through a detector. Depending upon the analyte different options are available, such as:
- Refractive index detector
- Diode array detector
- Mass spectrometer