Dextran-epichlorohydrin copolymer
A dextran-epichlorohydrin copolymer is a copolymer made from dextran and epichlorohydrin that is used in biochemistry for various types of chromatography .
properties
Dextran-epichlorohydrin copolymers are produced by crosslinking the biogenic homoglycan dextran from Leuconostoc mesenteroides with epichlorohydrin, whereupon it forms a relatively dimensionally stable gel and fairly uniform pore sizes with aqueous solutions . The amount of epichlorohydrin used determines the degree of crosslinking and thus also the pore size of the dextran-epichlorohydrin copolymer. Depending on the pore size, the gels have separation areas for molecules of different sizes. After cross-linking, the dried gel is ground and separated according to grain size, so that the dehydrated gel particles usually have a size between 40 and 150 micrometers.
Separation area in gel permeation chromatography
| Gel type | Separation area in Da |
|---|---|
| G-10 | ≤700 |
| G-15 | ≤1500 |
| G-25 | 1000-5000 |
| G-50 | 1500-30,000 |
| G-75 | 3000-80,000 |
| G-100 | 4000-150,000 |
| G-150 | 5000-300,000 |
| G-200 | 5000-600,000 |
Applications
Dextran-epichlorohydrin copolymers are used, among other things, as the stationary phase in gel chromatography . Dextran-epichlorohydrin copolymers are used in affinity chromatography , for immunoprecipitation and provided with other ionic functional groups in ion exchange chromatography and metal chelate affinity chromatography . Dextran-epichlorohydrin copolymers are sold in part under the brand name Sephadex (originally from Pharmacia ).
history
Dextran-epichlorohydrin copolymers were developed by Jerker Porath and Per Flodin from 1957 and used for gel permeation chromatography.
literature
- Friedrich Lottspeich , Joachim W. Engels (Ed.): Bioanalytik . 2nd edition, Spektrum Akademischer Verlag, Heidelberg 2006, ISBN 978-3827415202 .
- Hubert Rehm , Thomas Letzel: The Experimenter: Protein Biochemistry / Proteomics . 6th edition, Spektrum Akademischer Verlag, Heidelberg 2009. ISBN 978-3-8274-2312-2 .
Individual evidence
- ^ A b c d e Gary Walsh: Proteins: Biochemistry and Biotechnology. John Wiley & Sons, 2002. ISBN 9780471899075 . P. 122.
- ↑ J. Porath, P. Flodin: Gel filtration: a method for desalting and group separation . In: Nature (1959), Vol. 183 (4676), pp. 1657-9. PMID 13666849 .
- ↑ J. Porath: Gel filtration of proteins, peptides and amino acids . In: Biochim Biophys Acta (1960), Vol. 39, pp. 193-207. PMID 14434211 .
- ^ P. Andrews: Estimation of the molecular weights of proteins by Sephadex gel filtration. In: Biochem J. (1964), Vol. 91 (2), pp. 222-33. PMID 4158310 ; PMC 1202876 (free full text).
- ^ J. Porath: From gel filtration to adsorptive size exclusion . In: J Protein Chem. (1997), Vol. 16 (5), pp. 463-8. PMID 9246630 .
- ↑ J. Porath, EB Lindner: Separation methods based on molecular sieving and ion exclusion . In: Nature (1961), Vol. 191, pp. 69-70. PMID 13737223 .
- ^ A. Tiselius, J. Porath, PA Albertsson: Separation and fractionation of macromolecules and particles . In: Science (1963) 141 : 13-20 (3575). PMID 13985156 .
- ^ R. Axén, J. Porath: Chemical coupling of enzymes to cross-linked dextran ('Sephadex') . In: Nature (1966), 210 : 367-9 (5034). PMID 5963228 .
- ^ R. Axén, J. Porath, S. Ernback: Chemical coupling of peptides and proteins to polysaccharides by means of cyanogen halides . In: Nature (1967), 214 : 1302-4 (5095). PMID 6056841 .
- ↑ J. Porath, R. Axén: Immobilization of enzymes to agar, agarose, and Sephadex supports . In: Methods Enzymol. (1976) Vol. 44, pp. 19-45. PMID 1021680 .