title: Cross-linked poly(N-acetylethylenimine) as an isoelectric focusing matrix.
abstract: Agarose and polyacrylamide are the gels used for most analytical and micropreparative electrophoresis of biopolymers. In an alternative approach that offers different physico-chemical properties from these standard gels, nonionic hydrogels and amphigels composed of poly(N-acetylethylenimine) (PAEI) and a variety of cross-linkers were prepared and used as anticonvective matrices for isoelectric focusing. PAEI was prepared from the ring opening, ionic polymerization of 2-methyl-2-oxazoline. The N-acetyl side chains were hydrolyzed with aqueous sodium hydroxide to produce secondary amine sites which were used for the attachment of cross-linkers. Several cross-linkers were tested for their suitability for electrophoresis, and the cross-linker system based on the Diels-Alder reaction between a furan and maleimide tethered to PAEI gave a moldable gel that can be reversibly converted to a sol at 80 degrees C. This gel was used for isoelectric focusing under both denaturing and nondenaturing conditions. Several protein standards were resolved as well as was achieved with polyacrylamide.
authors.affiliation: The Beckman Institute, California Institute of Technology, Division of Biology, Pasadena, USA.
authors.forename: T E
authors.initials: TE
authors.lastname: Zewert
authors.forename: M G
authors.initials: MG
authors.lastname: Harrington
mesh_terms: D000818:Animals; D002712:Chlorides / Q000737:chemistry; D003432:Cross-Linking Reagents / Q000737:chemistry; D003485:Cyanates / Q000737:chemistry; D003574:Cytochrome c Group / Q000032:analysis; D004305:Dose-Response Relationship, Drug; D004586:Electrophoresis / Q000295:instrumentation*; D004983:Ethanolamines / Q000737:chemistry*; D005021:Ethylamines / Q000737:chemistry*; D006801:Humans; D017953:Isocyanates; D007525:Isoelectric Focusing / Q000295:instrumentation* / Q000379:methods*; D008956:Models, Chemical; D011108:Polymers / Q000737:chemistry*; D011422:Propionates / Q000737:chemistry; D012709:Serum Albumin / Q000032:analysis; D012965:Sodium Chloride / Q000737:chemistry; D013388:Succinimides / Q000737:chemistry; D014168:Transferrin / Q000032:analysis
chemical_list: D002712:Chlorides; D003432:Cross-Linking Reagents; D003485:Cyanates; D003574:Cytochrome c Group; D004983:Ethanolamines; D005021:Ethylamines; D017953:Isocyanates; D011108:Polymers; D011422:Propionates; D012709:Serum Albumin; D013388:Succinimides; D014168:Transferrin; C121686:poly(N-acetylethylenimine); C015262:1,6-hexamethylene diisocyanate; D012965:Sodium Chloride; C011240:dithiobis(succinimidylpropionate); C019358:disuccinimidyl suberate