<P> In medicine, protein electrophoresis is a method of analysing the proteins mainly in blood serum . Before the widespread use of gel electrophoresis, protein electrophoresis was performed as free - flow electrophoresis (on paper) or as immunoelectrophoresis . </P> <P> Traditionally, two classes of blood proteins are considered: serum albumin and globulin . They are generally equal in proportion, but albumin as a molecule is much smaller and lightly, negatively - charged, leading to an accumulation of albumin on the electrophoretic gel . A small band before albumin represents transthyretin (also named prealbumin). Some forms of medication or body chemicals can cause their own band, but it usually is small . Abnormal bands (spikes) are seen in monoclonal gammopathy of undetermined significance and multiple myeloma, and are useful in the diagnosis of these conditions . </P> <P> The globulins are classified by their banding pattern (with their main representatives): </P> <Ul> <Li> The alpha (α) band consists of two parts, 1 and 2: <Ul> <Li> α - α - antitrypsin, α - acid glycoprotein . </Li> <Li> α - haptoglobin, α - macroglobulin, α - antiplasmin, ceruloplasmin . </Li> </Ul> </Li> <Li> The beta (β) band - transferrin, LDL, complement </Li> <Li> The gamma (γ) band - immunoglobulin (IgA, IgD, IgE, IgG and IgM). Paraproteins (in multiple myeloma) usually appear in this band . </Li> </Ul>

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