title: Development of crosslinked polyamines suitable for synthesizing complex ampholytes for isoelectric focusing.
abstract: Commercially available ampholytes used in isoelectric focusing applications vary widely from source to source in their resolving power. This study was initiated to develop alternative ampholyte formulations for high resolution preparative and analytical isoelectric focusing. Initial IR spectroscopy studies showed that divalent acid esters would efficiently crosslink available polyamines with complete consumption of ester. Fast atom bombardment mass spectroscopic analysis of resulting crosslinked polyamines showed extensive structural heterogeneity of the resulting polyamine mixture. Conversion of the polyamine mixture to functional zwitterions using alpha,beta-unsaturated carboxylic acids yielded mixtures giving smooth pH gradients in acrylamide gel isoelectric focusing. Further analysis of these mixtures in immobilized pH gradients showed increases in heterogeneity of available carrier species over similar zwitterion mixtures made using only commercially available polyamine monomers. The mixtures were also more heterogeneous than commercially available ampholytes when analyzed by picric acid precipitation in immobilized pH gradients.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Texas-Houston, Medical School 77225-0708, USA.
authors.forename: D R
authors.initials: DR
authors.lastname: McWhinney
authors.forename: P
authors.initials: P
authors.lastname: DeShong
authors.forename: L S
authors.initials: LS
authors.lastname: Rodkey
mesh_terms: D002021:Buffers; D003432:Cross-Linking Reagents; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D007525:Isoelectric Focusing / Q000379:methods*; D011073:Polyamines / Q000138:chemical synthesis*; D011095:Polyethylenes; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013055:Spectrophotometry, Infrared
chemical_list: D002021:Buffers; D003432:Cross-Linking Reagents; D007202:Indicators and Reagents; D011073:Polyamines; D011095:Polyethylenes