Devices and methods for enrichment and alteration of cells and other particles
The invention features a device for the deterministic separation of analytes coupled to a reservoir containing a reagent that alters a magnetic propert of the analyte. Exemplary methods include the enrichment of a sample in a desired analyte (e.g., using deterministic separation) or the alteration of a desired analyte in the device. The devices and methods may be advantageously employed to enrich for rare cells, e.g., fetal cells or epithelial cells, present in a sample, e.g., maternal blood.
1 . A device for producing a sample enriched in an analyte, said device comprising:
(a) a first channel comprising a structure that deterministically deflects particles having a hydrodynamic size above a critical size in a direction not parallel to the average direction of flow in said structure, wherein said particles are analyte particles or are a non-analyte component of said sample; and
(b) a reservoir fluidly coupled to an output of said first channel through which said analyte passes into said reservoir, wherein said reservoir comprises a reagent that alters a magnetic property of said analyte.
2 . The device of claim 1 , wherein said first channel is a microfluidic channel.
3 . The device of claim 1 , wherein said structure comprises an array of obstacles that form a network of gaps, wherein a fluid passing through said gaps is divided unequally into a major flux and a minor flux so that the average direction of the major flux is not parallel to the average direction of fluidic flow in said channel.
4 . The device of claim 3 , wherein said array of obstacles comprises first and second rows, wherein the second row is displaced laterally relative to the first row so that fluid passing through a gap in the first row is divided unequally into two gaps in the second row.
5 . The device of claim 1 , wherein said analyte has a hydrodynamic size greater than said critical size.
6 . The device of claim 1 , wherein said analyte has a hydrodynamic size smaller than said critical size.
7 . The device of claim 1 , further comprising a magnetic force generator capable of generating a magnetic field.
8 . The device of claim 7 , wherein said magnetic force generator comprises a region of magnetic obstacles disposed in a second channel.
9 . The device of claim 8 , wherein at least a portion of said magnetic obstacles comprise a permanent magnet.
10 . The device of claim 8 , wherein at least a portion of said magnetic obstacles comprise a non-permanent magnet.
11 . The device of claim 8 , wherein said obstacles are ordered in a two-dimensional array.
12 . The device of claim 8 , wherein said second channel is a microfluidic channel.
13 . The device of claim 1 , wherein said reservoir further comprises a second channel comprising a magnet.
14 . The device of claim 1 , wherein said reagent alters an intrinsic magnetic property of said one or more analytes.
15 . The device of claim 14 , wherein said reagent comprises sodium nitrite.
16 . The device of claim 1 , wherein said reagent binds to said one or more analytes.
17 . The device of claim 16 , wherein said reagent comprises a magnetic particle.
18 . The device of claim 17 , wherein said magnetic particle comprises an antibody or an antigen-binding fragment thereof.
19 . The device of claim 18 , wherein said antibody is anti-CD71, anti-CD36, anti-CD45, anti-GPA, anti-antigen i, anti-CD34, or anti-fetal hemoglobin.
20 . The device of claim 16 , wherein said reagent comprises holo-transferrin.
21 . A method for producing a sample enriched in a first analyte relative to a second analyte, said method comprising:
(a) applying at least a portion of said sample to a device comprising a structure that deterministically deflects particles having a hydrodynamic size above a critical size in a direction not parallel to the average direction of flow in said structure, thereby producing a second sample enriched in said first analyte and comprising said second analyte;
(b) combining said second sample with a reagent that alters a magnetic property of said first analyte to produce an altered first analyte; and
(c) applying a magnetic field to said second sample, wherein said magnetic field generates a differential force to physically separate said altered first analyte from said second analyte, thereby producing a sample enriched in said first analyte.
22 . The method of claim 21 , wherein said reagent binds to said first analyte.
23 . The method of claim 21 , wherein said reagent alters an intrinsic magnetic property of said first analyte.
24 . The method of claim 23 , wherein said reagent comprises sodium nitrite.
25 . The method of claim 21 , wherein said reagent comprises a magnetic particle that binds to or is incorporated into said first analyte.
26 . The method of claim 25 , wherein said magnetic particle comprises an antibody or an antigen-binding fragment thereof.
27 . The method of claim 26 , wherein said antibody is anti-CD71, anti-GPA, anti-antigen i, anti-CD45, anti-CD34, or anti-fetal hemoglobin.
28 . The method of claim 21 , wherein said analyte has a hydrodynamic size greater than said critical size.
29 . The method of claim 21 , wherein said analyte has a hydrodynamic size smaller than said critical size.
30 . The method of claim 21 , wherein said sample comprises a maternal blood sample.
31 . The method of claim 21 , wherein said first analyte is a cell, an organelle, or a virus.
32 . The method of claim 31 , wherein said cell is a bacterial cell, a fetal cell, or a blood cell.
33 . The method of claim 32 , wherein said blood cell is a fetal red blood cell.
34 . The method of claim 31 , wherein said organelle is a nucleus.
35 . A method of producing a sample enriched in red blood cells relative to a second blood component, said method comprising:
(a) contacting a sample comprising red blood cells with a reagent that oxidizes iron to produce oxidized hemoglobin; and
(b) applying a magnetic field to said sample, wherein said red blood cells having oxidized hemoglobin are attracted to said magnetic field to a greater extent than said second blood component, thereby producing said sample enriched in said red blood cells.
36 . The method of claim 35 , wherein said red blood cells are fetal red blood cells.
37 . The method of claim 36 , wherein said second blood component is a maternal blood cell.
38 . The method of claim 35 , wherein prior to said step (a), said sample is enriched for said red blood cells.
39 . The method of claim 38 , wherein said enriching is performed by applying at least a portion of said sample to a device comprising a structure that deterministically deflects particles having a hydrodynamic size above a critical size in a direction not parallel to the average direction of flow in said structure.
40 . The method of claim 39 , wherein fetal red blood cells are enriched relative to maternal red blood cells.
41 . A device for producing a sample enriched in red blood cells, said device comprising:
(a) an analytical device that enriches said red blood cells based on size, shape, deformability, or affinity; and
(b) a reservoir comprising a reagent that oxidizes iron, wherein said reagent increases the magnetic responsiveness of said red blood cells.
42 . The device of claim 41 , wherein said analytical device comprises a first channel comprising a structure that deterministically deflects particles having a hydrodynamic size above a critical size in a direction not parallel to the average direction of flow in said structure.
43 . The device of claim 41 , wherein said reagent is sodium nitrite.