Past Separations
The documented history of separation science extends back over 200 years. Here, we sumarize the key developments in the field.
1807
Ferdinand Frederic Reuss observes that application of an electric field caused clay particles to migrate in water, the basis for modern electrophoresis.
Several German chemists explore the phenomenon first observed by early dye chemists: dye solution migrates up an inserted material by capillary action, with the dye components separating into distinct bands.
1861
Frederich Goppelsroder first to describe separation of dyes by capillary action as ‘capillary analysis’.
1901
Russian botanist Mikael Tswett coins the term ‘chromatography’ from the Greek words meaning colour writing to describe the physiochemical basis for the separation when he used calcium carbonate (chalk) to separate chlorophylls and carotenoids in plant extracts.
Tswett’s work is mostly unknown within the field as he publishes his findings only in Russian or German botanical journals.
1930
Richard Kuhn and Edgar Lederer ‘re-discover’ Tswett’s technique for the separation of carotenoids and amino acids.
1941-1952
Initially, Archer Martin and Richard Synge use chromatography to study the amino acid composition of wool. Their method, defined as partition chromatography, is physically the same as Tsvett’s yet conceptually different in that one liquid is bound to a finely grained solid (usually silica gel) packed in a glass tube, and a second, immiscible liquid is percolated through it. Separation is based on differential partitioning of molecules between the stationary liquid and the mobile liquid phase. Lack of reproducibility in the properties of silica gel and packing glass tubes also leads them to consider new formats, the most successful using paper as the stationary medium. Interestingly, in their initial publications they also describe what they believe, based on their theory, will be the future potential developments and limitations of this technique. Many of these could be not tested with the technology available at the time, but have since become a focus of some of the most exciting new developments in separation science.
1952
Archer Martin and Richard Synge are awarded the Nobel Prize in Chemistry "for their invention of partition chromatography" and introduce a model that suggests other systems, such as using gas as the moving phase, a mathematical theory and its application to the separation of amino acids and peptides with wider impact in biochemical studies. Archer Martin and Anthony James extend Martin and Synge’s concepts to the use of a gaseous mobile phase.
1957
Michael Golay, a consultant for the Perkin-Elmer Corporation, develops modern gas chromatography when he identifies from theoretical work that a very long capillary column with its wall coated in a thin film of liquid can yield superior separations – the first description of capillary gas chromatography.
1960s
J. Calvin Giddings and Csaba Horváth provide the theoretical and practical basis for modern high performance liquid chromatography (HPLC), requiring the development of pumps that could deliver liquid at a defined flow rate at high pressures and detectors that could sense small sample sizes.
1970s
Lloyd Snyder, John Dolan and Russel Gant develop a theoretical framework for gradient elution as a solution to the 'general elution problem' (i.e., that, for most samples, no one set of conditions is suitable for elution of all components in a reasonable time and with reasonable peak shape). Snyder also provides a description of various solvent properties important in liquid chromatography to control separation selectivity: the acidic, basic and dipolar nature of the solvents, and plots them as a triangle, often described as the Snyder solvent selectivity triangle.
You want to learn more about future separations? Keep on reading.
Emily Hilder is Professor and ARC Future Fellow in the Australian Centre for Research on Separation Science (ACROSS) and School of Chemistry at the University of Tasmania. Her research focuses on the design and application of new polymeric materials, in particular polymer monoliths, in all areas of separation science. She is also interested in the development of miniaturised analytical systems, particularly for applications in clinical diagnostics and remote monitoring. She has over 95 peer-reviewed publications and was recently recognised as the LCGC Emerging Leader in Chromatography (2012). She is also an Editor of the Journal of Separation Science.
