Processes for the preparation and separation of macromolecules

A process for the electrophoretic separation of charged macromolecules which comprises applying to said macromolecules a periodic sequence of pulses with each period comprising a multiplicity of electric field pulses of negative polarities and positive polarities wherein the negative polarity pulses are applied for a longer time duration than the positive polarity pulses, and the average intensity of the negative polarity pulses is less than the average intensity of the positive polarity pulses and wherein zero integrated field electrophoresis is applied whereby the net integrated value of the electric field pulses during one complete period is zero.

A process for the electrophoretic separation of charged macromolecules which comprises applying to said macromolecules a periodic sequence of pulses with each period comprising a multiplicity of electric field pulses of negative polarities and positive polarities wherein the negative polarity pulses are applied for a longer time duration than the positive polarity pulses, and the average intensity of the negative polarity pulses is less than the average intensity of the positive polarity pulses and wherein field pulse durations, and field intensities are changed during the process.

A process for the separation of charged macromolecules which comprises repeatedly applying to said macromolecules contained in an electrophoresis device a periodic sequence of pulses with each period comprising pulses of a first electric field and pulses of a second electric field, and wherein the fields are of opposite polarity and along a single dimension;

• the second field is of lower intensity than the first field;
• and the second field is applied for a longer duration than the first field for each period.

A process for the separation of charged macromolecules which comprises repeatedly applying to said macromolecules contained in an electrophoresis device a periodic sequence of pulses with each period comprising pulses of a first electric field and pulses of a second electric field and wherein the fields are of opposite polarity and along a single dimension;

• the second field is of lower intensity than the first field;
• and the second field is applied for a longer duration than the first field for each period and wherein zero integrated field electrophoresis is applied whereby the net integrated value of the first and second electric fields during one complete period is about zero.