Apparatus and method for using bi-directional capillary electrophoresis

A microfluidic bi-directional capillary electrophoresis device, comprising:

• a middle column;
• the middle column intersecting a first uncharged channel and a second uncharged channel at an intersection point wherein the middle column is approximately perpendicular to the first uncharged channel and the second uncharged channel;
• and
• a negative electrode in communication with the first uncharged channel and a positive electrode in communication with the second uncharged channel,
• wherein a mixture of anions and cations may be separated by drawing the cations toward the negative electrode and drawing the anions towards the positive electrode.

A method of separating a sample of anions and cations, comprising:

• delivering the sample to a middle column of a bi-directional capillary electrophoresis device;
• providing a first uncharged channel and a second uncharged channel approximately perpendicular to the middle column wherein the middle column intersects the first uncharged channel and the second uncharged channel at an intersection point;
• positioning a negative electrode in communication with the first uncharged channel thereby drawing cations into the first uncharged channel;
• and
• positioning a positive electrode in communication with the second uncharged channel thereby drawing anions into the second uncharged channel.

A method of separating a sample of anions and cations on a microfluidic device, comprising:

• delivering the sample to a middle column of a b-idirectional capillary electrophoresis device;
• providing a first uncharged channel and a second uncharged channel approximately perpendicular to the middle column wherein the middle column intersects the first uncharged channel and the second uncharged channel at an intersection point;
• positioning a negative electrode in communication with the first uncharged channel thereby drawing cations into the first uncharged channel;
• and
• positioning a positive electrode in communication with the second uncharged channel thereby drawing anions into the second uncharged channel.