Small separation apparatus

An electrophoresis apparatus for processing compounds in small sample volumes comprising:

• (a) a cathode in a static cathode buffer zone or compartment;
• (b) an anode in a static anode buffer zone or compartment, the cathode disposed relative to the anode so as to be adapted to generate an electric field in an electric field area therebetween upon application of a voltage potential between the cathode and anode;
• (c) a removable cartridge disposed in the electric field area between the anode and cathode, the cartridge comprising a first non-isoelectric separation barrier;
• a second non-isoelectric separation barrier disposed between the cathode buffer zone and the first barrier so as to define a first chamber having an interstitial volume of less than 5 mL therebetween;
• and also a third non-isoelectric separation barrier disposed between the anode buffer zone and the first barrier so as to define a second chamber having a interstitial volume of less than 5 mL therebetween;
• wherein in use, the removable cartridge containing the non-isoelectric separation barriers is disposed in the apparatus forming the cathode buffer zone and the anode buffer zone, electrophoretic buffer is disposed in the cathode buffer zone, the anode buffer zone and at least one of the first and second chambers, a sample containing one or more compounds is provided to a selected one of the first and second chambers;
• wherein upon application of the voltage potential, a selected compound is removed from the sample through the first separation barrier, and provided to the other of the first and second chambers;
• and wherein there is substantially no circulation of buffer or sample in the buffer zones, the first chamber or the second chamber.

An electrophoresis apparatus for processing compounds in small sample volumes comprising:

• (a) a cathode in a static cathode buffer zone or compartment;
• (b) an anode in a static anode buffer zone or compartment, the cathode disposed relative to the anode so as to be adapted to generate an electric field in an electric field area therebetween upon application of a voltage potential between the cathode and anode;
• (c) a removable cartridge disposed in the electric field area between the anode and cathode, the cartridge comprising a first non-isoelectric separation barrier;
• a second non-isoelectric separation barrier disposed between a selected one of the cathode buffer zone and the anode buffer zone and the first barrier so as to define a first chamber having an interstitial volume of less than 5 mL therebetween;
• and also
• a third non-isoelectric separation barrier disposed between the anode buffer zone an the first barrier so as to define a second chamber having an interstitial volume of less than 5 mL therebetween;
• wherein in use, the removable cartridge containing the non-isoelectric separation barriers is disposed in the apparatus forming the cathode buffer zone and the anode buffer zone, electrophoretic buffer is disposed in the cathode buffer zone and the anode buffer zone, and at least one of the first chamber and second chamber, a sample containing one or more compounds is provided to the first chamber;
• wherein upon application of the voltage potential a selected compound is removed from the sample through the first or second non-isoelectric separation barriers and provided to the second chamber;
• and wherein there is substantially no circulation of buffer or sample in the buffer zones or the first chamber.

A method for de-salting or dialysing a small volume sample containing at least one compound and one or more salts comprising:

• (a) providing an apparatus comprising a cathode in a static cathode buffer zone or compartment;
• an anode in a static anode buffer zone or compartment, the cathode disposed relative to the anode so as to be adapted to generate an electric field in an electric field area therebetween upon application of a voltage potential between the cathode and anode;
• a first non-isoelectric separation barrier disposed in the electric field area;
• and a second non-isoelectric separation barrier disposed between a selected one of the cathode buffer zone and the anode buffer zone and the first barrier so as to define a first chamber having an interstitial volume of less than 5 mL between the first separation barrier and the second separation barrier;
• (b) adding buffer to the cathode and anode buffer zones or compartments;
• (c) placing a sample in the first chamber;
• and
• (d) applying a voltage potential wherein upon application of the voltage potential, one or more salts in the sample are removed from the sample through a selected one of the first and second separation barriers and provided to a selected one of the cathode buffer zone and the anode buffer zone, wherein at least one compound is substantially retained in the first chamber, and wherein there is substantially no circulation of buffer or sample in the buffer zones and the first chamber.

A method for de-salting or dialysing a small volume sample containing at least one compound and one or more salts comprising:

• (a) providing an apparatus comprising a cathode in a static cathode buffer zone or compartment;
• an anode in a static anode buffer zone or compartment, the cathode disposed relative to the anode so as to be adapted to generate an electric field in an electric field area therebetween upon application of a voltage potential between the cathode and anode;
• a first non-isoelectric separation barrier disposed in the electric field area;
• a second non-isoelectric separation barrier disposed between the cathode buffer zone and the first barrier so as to define a first chamber having an interstitial volume of less than 5 mL between the first separation barrier and the second separation barrier;
• and a third non-isoelectric separation barrier disposed between the anode buffer zone and the first barrier so as to define a second chamber having a interstitial volume of less than 5 mL between the third separation barrier and the first barrier;
• (b) adding buffer to the cathode and anode buffer zones or compartments and to at least one of the chambers;
• (c) placing a sample in a selected one of the first and second chambers;
• and
• (d) applying a voltage potential between the first and second chambers, wherein upon application of the voltage potential one or more salts in the sample are removed from the mixture through a selected one of the first separation barrier and provided to the other of the first and second chamber, wherein at least one compound is substantially retained in first chamber from which the salt is removed, wherein there is substantially no circulation of buffer or sample in the buffer zones, the first chamber, and the second chamber.