- Separation and quantitative analysis of components in organic, inorganic, pharmaceutical, and biochemical mixtures

- Analysis of organic and inorganic compounds for impurities

- Isolation of pure compounds from mixtures

- Analysis of solvents for low-level organic contaminants

- Monitoring the stability of polymers during aging tests

- Analysis of foods and natural products for high molecular weight sugars

- Analysis of thermally unstable pesticides

- Isolation of microgram amounts of material for identification purposes

- Isolation of large quantities (1 to 10 g) of purified compounds for synthetic purposes

- Form: Solids (dissolved in a suitable solvent) or liquids

- Size: 0.1 to 1 g generally required for quantitative work; however, as little as 10^-5 g may be analyzed. Larger quantities may be required for preparative work

- Preparation: Sample must be dissolved in a suitable solvent at concentrations of 0.1 to 100 mg/mL (although neat liquids may be analyzed). Filtration or extraction of the solution may be necessary. Injection volume 0.1 mL is typical

- Solids must be freely soluble in carrier solvent, and liquids must be miscible with it

- Difficult to make unambiguous identification of a particular component; subsequent analysis by infrared spectroscopy or mass spectrometry may be necessary

- Requires 15 to 60 min for an analysis; several replicate analyses are usually performed

- May require one-half day to change column, solvents, or detector for a particular analysis

- Lengthy development may be required if method is not available

- Gas chromatography: Restricted to volatile or pyrolyzable samples

- Mass spectrometry, infrared spectroscopy, nuclear magnetic resonance: Used to identify components isolated by liquid chromatography

- Ion chromatography: A type of liquid chromatography restricted to the analysis of ionic species