SSC buffer

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In biochemistry and molecular biology, saline-sodium citrate (SSC) buffer is used as a hybridization buffer, to control stringency for washing steps in protocols for Southern blotting, in situ hybridization, DNA Microarray or Northern blotting. 20X SSC may be used to prevent drying of agarose gels during a vacuum transfer.

A 20X stock solution consists of 3 M sodium chloride and 300 mM trisodium citrate (adjusted to pH 7.0 with HCl).

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Northern blot Molecular biology technique

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DNA microarray Collection of microscopic DNA spots attached to a solid surface

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Southwestern blot Molecular biology technique

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Edwin Southern

Sir Edwin Mellor Southern is an English Lasker Award-winning molecular biologist, Emeritus Professor of Biochemistry at the University of Oxford and a fellow of Trinity College, Oxford. He is most widely known for the invention of the Southern blot, published in 1975 and now a common laboratory procedure.

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The following outline is provided as an overview of and topical guide to genetics:

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The northwestern blot, also known as the northwestern assay, is a hybrid analytical technique of the western blot and the northern blot, and is used in molecular biology to detect interactions between RNA and proteins. A related technique, the western blot, is used to detect a protein of interest that involves transferring proteins that are separated by gel electrophoresis onto a nitrocellulose membrane. A colored precipitate clusters along the band on the membrane containing a particular target protein. A northern blot is a similar analytical technique that, instead of detecting a protein of interest, is used to study gene expression by detection of RNA on a similar membrane. The northwestern blot combines the two techniques, and specifically involves the identification of labeled RNA that interact with proteins that are immobilized on a similar nitrocellulose membrane.

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