Method of separation of polymers
A method of using electrokinetics for separating particles in a buffer solution is provided, where a chromatographic column is provided having a non-uniform internal longitudinal cross-section. At least one main inlet for inputting solution and at least one main outlet for outputting solution are provided. At least one sample inlet and at least one sample outlet are provided. The particle is introduced to the column from the sample inlet and fractionated samples are eluted from the sample outlet, where quality control and further analysis are enabled. An electric field is applied to the solution in the column to generate a charged double layer at a solid-liquid interface within the column. The electric filed moves ions within the double layer, and a non-uniform velocity profile is induced to the buffer solution. The moving ions carry the particles along the column and the particles are separated according to size or charge.
1. A method of using electrokinetics for separating charged and uncharged particles in a buffer solution, the method comprising:
a. providing a chromatographic column, wherein said column comprises a channel having a continuously varying geometry along an x-axis, wherein said continuously varying geometry is disposed to provide a continuous distribution of velocities along a y-axis of said channel of a moving buffer solution, wherein said moving buffer solution moves in a continuous x-direction, wherein curved channel walls provide longer path lengths along said channel walls than path lengths along a center of said channel;
b. providing at least one main inlet and at least one main outlet, wherein said buffer solution is input to said main inlet and output from said main outlet;
c. applying an electric field to said solution in said column, wherein said electric field moves said buffer solution along said curved channel walls by electroosmosis, wherein a charged double layer is disposed at channel-buffer solution interface, wherein said charged double layer is disposed to drag said buffer solution along said curved channel walls in said continuous x-direction from said inlet to said outlet; and
d. providing at least one sample inlet and at least one sample outlet, wherein said sample comprises charged and uncharged particles having varying sizes, wherein said uncharged particles are impervious to said electric field, wherein said curved channel walls are disposed to provide non-uniform flow of said buffer solution that moves in said continuous x-direction, wherein said non-uniform flow of said buffer solution moves said charged particles and said uncharged particles at different velocities along said curved channel walls in said continuous x-direction according to their charge and size along said column and said particles are eluted from said sample outlet according to size and charge.
2. The method of claim 1 , wherein said channel having said continuously varying geometry along said x-axis comprises a generally counter undulating-shape profile, whereby said counter undulation is between a first wall cross-section and a second wall cross-section.
3. The method of claim 2 , wherein said undulation has a peak to peak distance, wherein said peak to peak distance is in a range from 1 μm to 500 μm.
4. The method of claim 2 , wherein said undulation has an undulation linear density ranging from 0.05 peaks/μm to 1 peak/μm.
5. The method of claim 2 , wherein said undulation first wall cross-section and said second wall cross-section have a ratio of a widest separation and a narrowest separation, wherein said ratio is greater than or equal to one.
6. The method of claim 1 , wherein said column has a shape selected from the group consisting of curved, circular, and spiral.
7. The method of claim 1 , wherein said solution is selected from the group consisting of water, phosphate buffered saline, TTE (0.5 M Tris, 0.5 M TAPS, 0.02 M EDTA) and any water-based solution.
8. The method of claim 1 , wherein said particles have a particle size ranging from 1 nm to 500 μM.