Methods and systems for differential extraction

1. A method comprising:

(a) placing a biological sample in a first compartment of a system, wherein the first compartment comprises a cell-trapping matrix, wherein the compartment is exposed to a magnetic force external to the compartment;

(b) capturing the sperm cells and the non-sperm cells with the cell-trapping matrix;

(c) incubating the cell-trapping matrix and the captured sperm cells and non-sperm cells in a selective sperm lysis buffer to form a sperm cell lysate, the selective sperm lysis buffer comprising about 1 M KCl and 200 mM DTT;

(d) binding sperm cell DNA from the sperm cell lysate to a plurality of DNA-binding particles; and

(e) eluting the sperm cell DNA from the DNA-binding particles.

2. The method of claim 1 , wherein the capturing the sperm cells and the non-sperm cells with the cell-trapping matrix comprises applying a Magnetic force to the cell-trapping matrix.

3. The method of claim 1 , wherein the incubating the cell-trapping matrix and the captured sperm cells and non-sperm cells in a selective sperm lysis buffer occurs in the first compartment of system.

4. The method of claim 3 , wherein the binding the sperm cell DNA to a plurality of DNA-binding particles occurs in a second compartment of the system.

5. The method of claim 4 , wherein the eluting the sperm cell DNA from the DNA-binding particles occurs in the second compartment of the system.

6. The method of claim 4 , wherein the sperm cell lysate is moved from the first compartment to the second compartment.

7. The method of claim 1 , wherein the incubating the cell-trapping matrix and the captured sperm cells and non-sperm cells in a selective sperm lysis buffer occurs in a second compartment of the system.

8. The method of claim 7 , wherein the binding the sperm cell DNA to a plurality of DNA-binding particles occurs in a second compartment of the system.

9. The method of claim 8 , wherein the eluting the sperm cell DNA from the DNA-binding particles occurs in a third compartment of the system.

10. The method of claim 7 , wherein the cell-trapping matrix and the captured sperm cells and non-sperm cells are moved from the first compartment to the second compartment using a magnetic force.

11. The method of claim 1 , wherein the non-sperm cells remain captured on the cell-trapping matrix after incubating the cell-trapping matrix in the selective sperm lysis buffer.

12. The method of claim 11 , wherein the non-sperm cells are lysed and the non-sperm cell DNA is bound to the cell-trapping matrix.

13. The method of claim 11 , wherein the non-sperm cells are lysed and the non-sperm cell DNA is bound to a second plurality of DNA-binding particles.

14. A kit comprising: a multi-compartment container, wherein at least one compartment is exposed to a magnetic force external to the compartment and wherein at least one compartment comprises a selective sperm lysis buffer, the selective sperm lysis buffer comprising about 1 M KCl and 200 mM DTT.

15. The kit for differential extraction of sperm cells of claim 14 , wherein at least one compartment of the multi-compartment container comprises a cell-trapping matrix.

16. The kit for differential extraction of sperm cells of claim 14 , wherein at least one compartment of the multi-compartment container comprises a plurality of DNA-binding particles.

17. The kit for differential extraction of sperm cells of claim 14 , wherein at least one compartment of the multi-compartment container comprises an elution buffer.

18. The kit for differential extraction of sperm cells of claim 14 ,

wherein the multi-compartment container comprises:

a first compartment comprising a cell-trapping matrix;

a second compartment comprising a cell wash buffer;

a third compartment comprising the selective sperm lysis buffer;

a fourth compartment comprising a plurality of DNA binding particles;

a fifth compartment comprising a DNA wash buffer; and

a sixth compartment comprising an elution buffer.