Electrophoresis is a method to separate body substances; this technique isolates them by placing the sample in an electric field. This phenomenon was first observed in 1807 by Reuss from Moscow State University who noticed that a constant electric field caused clay particles dispersed in water to migrate. It is caused by the presence of charges of the surface of the particle and the surrounding fluid. This was perfected in 1937 by Arne Tiselius (1902-1971). It is used in forensic medical laboratories; for example, to detect food-adulteration, such as soya in pork products. It also has many diagnostic applications, for instance, demonstrating the presence of abnormal blood-proteins, which are associated with some cancers. It is a very useful method that has also been used to detect the E-coli virus that attacked the crops in Germany. Using a simple concept that the substances are made of proteins, which are made of amino acids with positive and negative charges, scientists are able to separate the charges using an electric field. This is done using the gel electrophoresis apparatus where the sample of substance is dispensed into a well in the gel material. The gel is then placed in an electrophoresis chamber, which is connected to electricity. When the current is applied, the larger molecules move more slowly through the gel and the smaller molecules move faster. The different sized molecules form distinct bands on the gel which will be analysed by scientists.
During the latter day of the 19 century, several physicists, among them Sir William Crooks (1832-1919) in Britain and Heinrich Hertz (1857-1894) with his assistant Phillip Lenard (1862-1947) in Germany, were interested in the discharges produced by passing through partially evacuated glass tubes. On 8 November 1905, Wilhelm Röntgen (1845-1923), Professor of Physics at the German University of Wurzburg, made similar experiments. His almost chance observation that the discharge from...
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