Search PubMed⌕ Search

Biomedical subjects

A Chrambach

Publications and source records attributed to A Chrambach.

At least 217 records · Page 12Linked to original sources

Polyacrylamide gel electrophoresis.

Polyacrylamide gel electrophoresis (PAGE) provides a versatile, gentle, high resolution method for fractionation and physical-chemical characterization of molecules on the basis of size, conformation, and net charge. The polymerization reaction can be rigorously controlled to provide uniform gels of reproducible, measurable pore size over a wide range. This makes it possible to obtain reproducible relative mobility (Rf) values as physical-chemical constants. Application and extension of Ogston's (random fiber) model for a gel allows for calculation of molecular volume, surface area, or radius, free mobility, and valence from RJ measurements at several gel concentrations, to calculate gel concentration for optimal resolution, and to predict behavior of macromolecules on gel gradients by computerized methods. Extension of classical moving boundary theory has been used to generate multiphasic buffer systems (providing selective stacking, unstacking, restacking, and preparative steady-state-stacking) with known operating characteristics for any pH at 0 degrees and 25 degrees C. A general strategy for isolation of macromolecules and for macromolecular mapping has been developed. Preparative scale PAGE is operational for milligram loads and feasible for gram quantities.

Acrylic Resins↗

Unified theory for gel electrophoresis and gel filtration.

Unified theory for gel electrophoresis and gel filtration: The behavior of macromolecules in gel filtration and gel electrophoresis may be predicted from Ogston's model for a random meshwork of fibers. This model has been generalized to apply to nonspherical molecules and to several gel types. The model provides equations for inter-relationships between mobility, partition coefficient, gel concentration, and molecular radius; it gives a non-Gaussian distribution of pore sizes as a function of gel concentration. The theory defines conditions for optimal separation and optimal resolution in gel filtration and gel electrophoresis. The difference in resolving power between the two fractionation methods is accounted for by the fact that gel filtration is a form of partition chromatography.

Chromatography, Gel↗