Small separation apparatus

Abstract

An apparatus for processing compounds in small volumes by electrophoresis, the apparatus comprising: (a) a cathode in a static cathode buffer zone or compartment; (b) an anode in a static anode buffer zone or compartment, the anode disposed relative to the cathode 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 first separation barrier disposed in the electric field area; (d) a second 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 interstitial volume or chamber therebetween; wherein in use, electrophoretic buffer is disposed in the cathode buffer zone and the anode buffer zone, a sample constituent is provided to the first interstitial volume; wherein upon application of the voltage potential, a selected separation product is removed from the sample constituent through a selected one of the first and second separation barriers, and provided to a selected one of the cathode buffer and anode buffer zones; and wherein there is substantially no circulation of buffer or sample constituent in the buffer zones or the first interstitial volume.

1 . An apparatus for processing compounds in small volumes by electrophoretic separation, the apparatus comprising: 
 (a) a cathode in a static cathode buffer zone;    (b) an anode in a static anode buffer zone, the anode disposed relative to the cathode 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 first separation barrier disposed in the electric field area;    (d) a second 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 interstitial volume therebetween;    wherein in use, electrophoretic buffer is disposed in the cathode buffer zone and the anode buffer zone, a sample constituent is provided to the first interstitial volume; wherein upon application of the voltage potential, a selected separation product is removed from the sample constituent through a selected one of the first and second separation barriers and provided to a selected one of the cathode buffer and anode buffer zones; and wherein there is substantially no circulation of buffer or sample constituent in the buffer zones or the first interstitial volume.    
   
   
       2 . The apparatus according to  claim 1  wherein the small volume is less than about 5 mL.  
   
   
       3 . The apparatus according to  claim 2  wherein the small volume is up to about 2 mL.  
   
   
       4 . The apparatus according to  claim 3  wherein the small volume is from about 0.02 mL to about 0.1 mL.  
   
   
       5 . The apparatus according to  claim 1  wherein a ratio of sample to barrier surface area is less than about 1 mL/cm 2 .  
   
   
       6 . The apparatus according to  claim 5  wherein the ratio is up to about 0.5 mL/cm 2 .  
   
   
       7 . The apparatus according to  claim 6  wherein the ratio is up to about 0.1 mL/cm 2 .  
   
   
       8 . The apparatus according to  claim 7  wherein the ratio is about 0.02 mL/cm 2 .  
   
   
       9 . The apparatus according to  claim 1  wherein the first and second barriers are membranes and wherein such membranes are selected from the group consisting of electrophoresis separation membranes having a defined pore size or restriction membranes which allow flow of ions into and out of a chamber or compartment under the influence of an electric field but do not allow movement of macromolecules, or a combination thereof.  
   
   
       10 . The apparatus according to  claim 9  wherein at least one of the first and second membranes is an ion-permeable electrophoresis separation membrane comprised of polyacrylamide and having a molecule mass cut-off from about 1 kDa to about 1500 kDa.  
   
   
       11 . The apparatus according to  claim 10  wherein a selected one of the first and second membranes is an ion-permeable electrophoresis separation membrane comprised of polyacrylamide and having a molecule mass cut-off from about 1 kDa to about 1500 kDa and the other membrane is a restriction membrane comprised of polyacrylamide and having a molecular mass cut-off less than the separation membrane.  
   
   
       12 . The apparatus according to  claim 1  wherein the first and second separation barriers are membranes and such membranes are comprised of materials selected from the group consisting of ultrafiltration materials, electrodialysis materials, haemodialysis materials, and combinations thereof.  
   
   
       13 . The apparatus according to  claim 1  wherein the first and second separation barriers are adapted to be removed from the apparatus.  
   
   
       14 . The apparatus according to  claim 1  comprising a plurality of separation barriers spaced apart defining a plurality of interstitial volumes.  
   
   
       15 . An apparatus for processing compounds in small volumes by electrophoretic separation, the apparatus comprising: 
 (a) a cathode in a static cathode buffer zone;    (b) an anode in a static anode buffer zone, the anode disposed relative to the cathode 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 first separation barrier disposed in the electric field area;    (d) a second separation barrier disposed between the cathode buffer zone and the anode buffer zone and the first barrier so as to define a first interstitial volume therebetween;    (e) a third separation barrier disposed between the anode buffer zone and the first barrier so as to define a second interstitial volume therebetween;    wherein in use, electrophoretic buffer is disposed in the cathode buffer zone, the anode buffer zone and at least one of the first interstitial and second interstitial volumes, a sample constituent is provided to a selected one of the first interstitial and second interstitial volumes; wherein upon application of the voltage potential, a selected separation product is removed from the sample constituent, through the first separation barrier, and provided to the other of the first interstitial and second interstitial volumes; and wherein there is substantially no circulation of buffer or sample constituent in the buffer zones, the first interstitial volume or the second interstitial volume.    
   
   
       16 . The apparatus according to  claim 15  wherein the small volume is less than about 5 mL.  
   
   
       17 . The apparatus according to  claim 15  wherein the small volume is up to about 2 mL.  
   
   
       18 . The apparatus according to  claim 17  wherein the small volume is from about 0.02 mL to about 0.1 mL.  
   
   
       19 . The apparatus according to  claim 15  wherein a ratio of sample to barrier surface area is less than about 1 mL/cm 2 .  
   
   
       20 . The apparatus according to  claim 19  wherein the ratio is up to about a 0.5 mL/cm 2 .  
   
   
       21 - 36 . (canceled)