The success of chromatography as a technique for separating biomolecules is inevitably linked to the introduction of the gel filtration medium SephadexTM by Pharmacia AB in 1959. The now classical paper by Porath and Flodin  not only described one of the most significant advances ever made in the methodology of biochemistry, but also signaled the start of an unparalleled era of commercial development. Forty-five years later, the company behind Sephadex, now GE Healthcare, is a key part of one of the world's leading technology groups - and its chromatography products are used to purify over 90% of all FDA-approved biopharmaceuticals.
The event that ultimately led to the launch of Sephadex in 1959 can be traced to 1925 when Arne Tiselius became personal assistant to Professor Svedberg at the Department of Physical Chemistry, Uppsala University, Sweden. There, Tiselius developed moving boundary electrophoresis of proteins. In 1937 he was appointed Professor of Biochemistry and received the Nobel Prize for Chemistry in 1948.
Svedberg and Tiselius established a research tradition that attracted many innovative young scientists. In 1941, chemist Bjorn Ingelman joined Tiselius as a postgraduate student. Ingelman's studies involved dextran, a very high molecular weight glucose polysaccharide later commercialized by Pharmacia as a plasma volume expander. Chemists Jerker Porath and Per Flodin joined the group about ten years later.
In 1950, Ingelman was appointed Director of Research at Pharmacia, and in 1954 he invited Per Flodin to head the company's dextran research. Porath and Flodin continued to keep close contact and in early 1957, Porath reported that he had observed size-based, molecular sieving with almost quantitative recovery in glass columns packed with cross-linked dextran gels. Furthermore, the separation was quick, simple and reliable. The two immediately realized that this discovery had major scientific and commercial implications.
Following consultations between Pharmacia and Tiselius, patents were filed and product development started. The seminal paper describing gel filtration on Sephadex (Separation Pharmacia Dextran) appeared in Nature on June 13th, 1959, and Pharmacia launched Sephadex G-25 and Sephadex G-50 shortly afterwards. This coincided with a presentation of this 'new technique' by Flodin at the Gordon Conference in the US.
More publications and products soon followed. Pharmacia launched a series of improved gel filtration media, plus Sephadex ion exchangers. From the mid-1960s, SepharoseTM agarose-based media made a big impact on the company's development. In the following decade, affinity chromatography with, for example, Protein A Sepharose, as well as hydrophobic interaction chromatography grew in popularity. Significantly, these radical improvements in the way we purify proteins coincided with the rapid development of molecular biology (mRNA was discovered in 1961).
The 1980s witnessed yet another leap forward, this time with FPLCTM System. Like Sephadex before it, FPLC and its prepacked 10 µm MonoBeadsTM columns revolutionized protein separation. This competitive edge extended into the 1990s with SOURCETM 15 µm media and the ÄKTAdesignTM chromatography system platform.
Today, the chromatography business begun by Pharmacia in 1959 is part of GE Healthcare, a division of General Electric Company. Industrial-scale products like MabSelectTM protein A media and ChromaflowTM columns, as well as lab-scale HiTrapTM columns and ÄKTA systems feature prominently in research, development, and production facilities around the world.
Investment in R&D continues to match the renewed focus on protein studies. GE Healthcare is committed to extending the contribution to protein research initiated by Pharmacia into the future.
 Gel filtration: A method for desalting and group separation.
J. Porath, P. Flodin, Nature 183, 1657 (1959).
© 2004 All rights reserved General Electric Company.