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In the chromatography of a glow stick solution, a piece of chalk, a highly polar substance, is used as the stationary phase while comparatively less-polar solvents like acetone and 91% isopropyl alcohol can be used as the mobile phase. [1] Chalk is made up of calcium carbonate (CaCO 3) or calcium sulfate (CaSO 4), [3] and therefore contains ions.
Column chromatography in chemistry is a chromatography method used to isolate a single chemical compound from a mixture. Chromatography is able to separate substances based on differential absorption of compounds to the adsorbent; compounds move through the column at different rates, allowing them to be separated into fractions.
Planar chromatography is a separation technique in which the stationary phase is present as or on a plane. The plane can be a paper, serving as such or impregnated by a substance as the stationary bed ( paper chromatography ) or a layer of solid particles spread on a support such as a glass plate ( thin-layer chromatography ).
Size-exclusion chromatography, also known as molecular sieve chromatography, [1] is a chromatographic method in which molecules in solution are separated by their shape, and in some cases size. [2] It is usually applied to large molecules or macromolecular complexes such as proteins and industrial polymers . [ 3 ]
However, chromatographic methods for separation started being adopted in the early 1980s. Developments were ongoing in the time period between when Cohn fractionation started being used, in 1946, and when chromatography started being used, in 1983. In 1962, the Kistler & Nistchmann process was created which was a spinoff of the Cohn process.
Two-dimensional chromatography is a type of chromatographic technique in which the injected sample is separated by passing through two different separation stages. Two different chromatographic columns are connected in sequence, and the effluent from the first system is transferred onto the second column. [ 1 ]
The history of chromatography spans from the mid-19th century to the 21st. Chromatography, literally "color writing", [1] was used—and named— in the first decade of the 20th century, primarily for the separation of plant pigments such as chlorophyll (which is green) and carotenoids (which are orange and yellow).
Chiral chromatographic assay is the first step in any study pertaining to enantioselective synthesis or separation. This includes the use of techniques viz. gas chromatography (GC), high performance liquid chromatography (HPLC), chiral supercritical fluid chromatography (SFC), capillary electrophoresis (CE) [35] and thin-layer chromatography (TLC).