Radiation Safety
DNA samples for denaturing gel electrophoresis must be denatured prior to loading, to avoid time dependent denaturation artifacts on the gel. This is usually carried out by diluting the sample into 95% formamide and heating…
The electrophoretic analysis of single-stranded nucleic acids is complicated by the secondary structures assumed by these molecules. Separation on the basis of molecular weight requires the inclusion of denaturing agents which unfold the DNA or…
Tube gels were used frequently in the development of gel electrophoresis. Although they are still used for some applications (most notably for isoelectric focusing as part of 2D electrophoresis), tube gels have been superseded by…
A typical vertical apparatus used for sequencing is shown in the figure below. This system shows the components common to all vertical slab systems. The gel is cast between two glass plates, separated by spacers,…
A gel electrophoresis apparatus must allow the researcher to maintain a uniform electric field across the gel, provide cooling to prevent thermal artifacts, and allow access to the gel for sample loading and monitoring the…
Disulfide bonds between or within sample protein molecules can lead to the formation of aggregates as well as play a role in the binding of the subunits of many proteins. It is usually desirable to…
A crucial initial step in the electrophoretic separation of proteins is the solubilization of the sample molecules. This is especially true if there are extensive nonpolar interactions. Although urea in high concentration was often employed…
In most forms of electrophoresis, the solution perfusing the gel matrix typically contains one or more substances in addition to the buffer salts. Serving the purpose of modifying the properties of sample molecules, these additives…
Isotachophoresis is a method of electrophoresis that employs the basic principles of the stacking gel phase of multiphasic systems discussed in the preceding section. Employing nonsieving media, often low percentage polyacrylamide, isotachophoresis in its simplest…
Employing gel and buffer discontinuities to produce sharp separation among sample components, multiphasic electrophoresis design can improve the resolution of electrophoresis (especially protein electrophoresis). The system employs a separating gel in which the sample is…