Separation media for electrophoresis

In an electrophoretic device comprising an electrophoretic medium, the improvement which comprises:

• an electrophoretic medium comprising polymer chains having hydrophobic and hydrophilic moieties, wherein said medium is reversibly convertible between an electrophoretically sieving high viscosity state and a pumpable low viscosity state, said high viscosity state characterized by a viscosity of at least 100% greater than the viscosity of said medium in said low viscosity state, and wherein the conversion of said low viscosity state to said high viscosity state can be affected by a change in temperature, pH, solvent concentration, ionic strength, presence and concentration of a specific ion, or other property or combinations of properties of said medium which cause coalescence of said hydrophobic or hydrophilic groups on contiguous polymeric chains to form effective crosslinks of chains in said medium.

In an electrophoretic device comprising an electrophoretic medium, the improvement which comprises:

• an electrophoretic medium comprising polymer chains having ionic moieties and counter-ions, wherein said medium is reversibly convertible between an electrophoretically sieving high viscosity state and a pumpable low viscosity state, said high viscosity state characterized as having a viscosity of at least 100% greater as compared to the viscosity of said medium in said low viscosity state, and wherein the conversion of said low viscosity state to said high viscosity state is affected by exchange of said counter-ions with counter-ions of higher valency whereby ionic moieties on contiguous polymeric chains associate with said counter-ions of higher valency to form effective crosslinks of chains in said medium.

In an electrophoretic device comprising an electrophoretic medium, the improvement which comprises:

• an electrophoretic medium comprising polymer chains having chelatable ligand, wherein said medium is reversibly convertible between an electrophoretically sieving high viscosity state and a pumpable low viscosity state, said high viscosity state characterized as having a viscosity of at least 100% greater as compared to the viscosity of said medium in said low viscosity state, and wherein the conversion of said low viscosity state to said high viscosity state is affected by addition of a chelating agent whereby chelatable ligands on contiguous polymeric chains associate with said chelating agent to form effective crosslinks of chains in said medium.

In an electrophoretic device comprising an electrophoretic medium, the improvement which comprises:

• said electrophoretic medium comprising a composition reversibly convertible going from a first pumpable state to a second continuous electrophoretic gel state, wherein in said first pumpable state said composition is discrete particles of a cross-linked N-substituted polyacrylamide of a size in the range of 10 nm to 2 mm in an aqueous medium;
• and in said second state said particles are swollen and form a continuous gel, wherein said change from one state to another state occurs with a change in temperature.

In an electrophoretic device comprising an electrophoretic medium, the improvement which comprises:

• an electrophoretic medium comprising a dispersion of a particulate chemically-crosslinked microgel having particle sizes with a distribution of particles no smaller than about 10 nm and no larger than about 2 mm, wherein the weight concentration of said microgel in said dispersion is between about 1% and 50%, agarose, and wherein said medium is reversibly convertible between a pumpable low viscosity state and an electrophoretically sieving gel slab state, and wherein the conversion of said low viscosity state to said gel slab state occurs with a change in temperature.