title: Enhanced field strength and resolution in gel electrophoresis upon substitution of buffer by histidine at its isoelectric point.
abstract: Gel electrophoresis in isoelectric buffers, recently introduced by R. Westermeier and H. Schickle (Electrophoresis '95, Paris, Abstract No.3, 1995), was applied to the automated HPGE-1000 apparatus in the expectation to be able to increase the field strength under the limiting conditions of heat dissipation capacity and voltage of that apparatus. A previous attempt to achieve that aim by reduction of gel thickness had not yielded more than a twofold increment in resolving power. Replacing 0.2 X Tris-boric acid-EDTA (TBE) buffer, conventionally applied in the apparatus at 15 V/cm, by 0.05 M histidine, pH 7.6 (close to the pI of 7.47), allows one to increase the field strength to 60 V/cm, thus providing a nearly fivefold increment in resolution under otherwise identical conditions (fluorescein carboxylate-labeled conalbumin-sodium dodecyl sulfate (SDS) and soybean trypsin inhibitor-SDS samples, 10 degrees C, 4% MetaPhor agarose). An additional decrease in band dispersion can be obtained by decreasing the starting zone width through buffer dilution in the sample phase.
authors: Section on Macromolecular Analysis, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-1855, USA.
authors: N
authors: N
authors: Chen
authors: A
authors: A
authors: Chrambach
mesh_terms: D001888:Boric Acids / Q000737:chemistry; D002021:Buffers; D003207:Conalbumin / Q000737:chemistry; D004492:Edetic Acid / Q000737:chemistry; D004553:Electric Conductivity; D004587:Electrophoresis, Agar Gel / Q000379:methods*; D005452:Fluoresceins / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry; D006639:Histidine; D007526:Isoelectric Point; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D014325:Tromethamine / Q000737:chemistry; D014361:Trypsin Inhibitors / Q000737:chemistry
chemical_list: D001888:Boric Acids; D002021:Buffers; D005452:Fluoresceins; D005456:Fluorescent Dyes; D014361:Trypsin Inhibitors; C097499:fluorescein carboxylate; D014325:Tromethamine; D003207:Conalbumin; D012967:Sodium Dodecyl Sulfate; D006639:Histidine; D004492:Edetic Acid; C032688:boric acid