Method for extracting DNA

1. A method for extracting DNA, comprising the steps:

lysing cells in a first sample vessel ( 2 ) to form a lysate,

filtering the lysate through a lysate filter element ( 4 ) into a second sample vessel ( 1 ) to form a filtered lysate ( 11 ) comprising DNA released from the cells,

adding a DNA-adsorbing substance ( 15 ) to the second sample vessel ( 1 ) comprising the DNA released from the cells, wherein the DNA-adsorbing substance binds to and forms a complex with at least some of the DNA released from the cells,

closing the second sample vessel ( 1 ) with a wash filter element ( 3 ) formed of the same material as the lysate filter element ( 4 ),

delivering a wash fluid ( 12 ) into the second sample vessel ( 1 ) through the wash filter element ( 3 ), and

discharging the wash fluid ( 12 ) from the second sample vessel ( 1 ) through the wash filter element ( 3 ), wherein the complex is retained within the second sample vessel ( 1 ) by the wash filter element ( 3 ), and wherein any DNA that is not bound to the DNA-adsorbing substance is not retained by the wash filter element ( 3 ),

introducing an additional substance into the second sample vessel ( 1 ) in order to separate the DNA-adsorbing substance ( 15 ) from the DNA, producing free DNA, and

separating the DNA-adsorbing substance from the free DNA in the second sample vessel ( 1 ), leaving the free DNA in the second sample vessel ( 1 ).

2. The method as claimed in claim 1 , characterized in that the step of lysing cells to form a lysate comprises the following steps:

introducing cellular material ( 13 ) and a grinding element ( 14 ) into the first sample vessel ( 2 ), and

breaking down the cellular material ( 13 ) by moving the first sample vessel ( 2 ).

3. The method as claimed in claim 1 , characterized in that the wash filter element ( 3 ) or the lysate filter element ( 4 ) is arranged in a plunger ( 5 ), the plunger ( 5 ) being insertable into the second sample vessel ( 1 ) or the first sample vessel ( 2 ), and, through the plunger ( 5 ),

the wash fluid ( 12 ) being sucked into the second sample vessel ( 1 ) and pressed out of the second sample vessel ( 1 ), or

the lysate ( 11 ) being pressed out from the first sample vessel ( 2 ) into the second sample vessel ( 1 ).

4. The method as claimed in claim 3 , characterized in that the plunger ( 5 ) and the second sample vessel ( 1 ) or the first sample vessel ( 2 ) form a syringe.

5. The method as claimed in claim 1 , characterized in that the second sample vessel ( 1 ) is held in a holding device ( 6 ) throughout the entire method, and/or the first sample vessel ( 2 ) is held in an additional holding device at least during the step of filtering the lysate ( 11 ).

6. The method as claimed in claim 5 , characterized in that the holding element ( 6 ) simultaneously holds a multiplicity of second sample vessels ( 1 ), and/or the additional holding element simultaneously holds a multiplicity of first sample vessels ( 2 ), so that the method is applied simultaneously to the multiplicity of second sample vessels ( 1 ) and/or first sample vessels ( 2 ).

7. The method as claimed in claim 4 , characterized in that a multiplicity of plungers ( 5 ) are fixed on a carrier element ( 7 ), so that, at the same time, the multiplicity of plungers ( 5 ) are inserted simultaneously into the multiplicity of second sample vessels ( 1 ) and/or first sample vessels ( 2 ).

8. The method as claimed in claim 7 , characterized in that the step of delivering the wash fluid ( 12 ) and/or the step of discharging the wash fluid ( 12 ), and/or the step of filtering the lysate ( 11 ), are carried out by moving the carrier element ( 7 ) and the holding element ( 6 ) and/or the additional holding element relative to one another.

9. The method as claimed in claim 7 , characterized in that the step of delivering the wash fluid ( 12 ) is carried out by simultaneous suction of wash fluid ( 12 ) through the multiplicity of plungers ( 5 ) from a common reservoir ( 8 ) or from an individual reservoir ( 9 ) provided for each plunger ( 5 ).

10. The method as claimed in claim 9 , characterized in that the reservoir ( 8 ) is subdivided by at least one subdivision element ( 10 ) into individual subreservoirs ( 11 ) for each plunger ( 5 ).

11. The method as claimed in claim 1 , characterized in that the steps of delivering the wash fluid ( 12 ) and of discharging the wash fluid ( 12 ) are carried out repeatedly.

12. The method as claimed in claim 1 , characterized in that after the step of delivering the wash fluid ( 12 ) and before the step of discharging the wash fluid ( 12 ), air is delivered to the second sample vessel ( 1 ).

13. The method as claimed in claim 1 , characterized in that after the step of delivering the wash fluid ( 12 ) and before the step of discharging the wash fluid ( 12 ), the second sample vessel ( 1 ) is moved circularly or alternatingly.

14. The method as claimed in claim 1 , characterized in that the wash filter element ( 3 ) and the lysate filter element ( 4 ) are identical, and/or the second sample vessel ( 1 ) and the first sample vessel ( 2 ) are constructed identically.

15. The method as claimed in claim 1 , characterized in that the step of lysing cells to form a lysate ( 11 ) comprises the following steps:

introducing cellular material ( 13 ) and a grinding ball ( 14 ) into the first sample vessel ( 2 ), and

breaking down the cellular material ( 13 ) by moving the first sample vessel ( 2 ) with frequency in an alternating movement.

16. The method as claimed in claim 9 , characterized in that the reservoir ( 8 ) is subdivided by at least one retractable subdivision element ( 10 ) into individual subreservoirs ( 11 ) for each plunger ( 5 ).

17. The method as claimed in claim 1 , characterized in that after the step of delivering the wash fluid ( 12 ) and before the step of discharging the wash fluid ( 12 ), air is delivered to the second sample vessel ( 1 ), the air being delivered to the second sample vessel ( 1 ) in the same way as the wash fluid ( 12 ).

18. The method as claimed in claim 1 , characterized in that after the step of delivering the wash fluid ( 12 ) and before the step of discharging the wash fluid ( 12 ), the second sample vessel ( 1 ) is moved with a frequency, circularly or alternatingly.

19. The method as claimed in claim 1 , characterized in that the additional substance is a chaotropic salt disrupts binding between the DNA and DNA-adsorbing substance to form a mixture of free DNA and the DNA-adsorbing substance.

20. The method as claimed in claim 19 , characterized in that the DNA-adsorbing substance is coated on magnetic beads, and wherein a magnet is used to separate the DNA-adsorbing substance from the free DNA in the second sample vessel ( 1 ).