gp 80 – form tight aggregate

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#Unit 13. Methods in Biology

Three basically different electrophoretic separation methods are performed in practice nowadays

 Electrophoresis, sometimes called Zone Electrophoresis (ZE) GE

 Isotachophoresis (ITP) SDS PAGE

Isoelectric focusing (IEF).

#Id: 2473

#Unit 13. Methods in Biology

In ZE a homogeneous buffer system is used over the whole separation time and range so as to ensure a constant pH value.

#Id: 2474

#Unit 13. Methods in Biology

In ITP, the separation is carried out in a discontinuous buffer system. The ionized sample migrates between a leading electrolyte with a high mobility and a terminating – sometimes called trailing – ion with a low mobility, all of them migrating with the same speed.

#Id: 2475

#Unit 13. Methods in Biology

IEF takes place in a pH gradient and can only be used for amphoteric substances such as peptides and proteins. The charged molecules move toward the anode or the cathode until they reach a position in the pH gradient where their net charges are zero. This pH value is the “isoelectric point” (pI) of the substance.

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#Unit 13. Methods in Biology

Agarose is one of the components of agar, which is a mixture of polysaccharides isolated from certain seaweeds and usually used at concentrations of between 1% and 3% in labs. 

#Id: 2477

#Unit 13. Methods in Biology

Agarose gels are formed  by suspending dry agarose in aqueous buffer, then boiling the mixture until a clear solution forms.