Abstract:
A cassette for preparing a sample is disclosed herein. The cassette includes a housing, which encloses the structures and the processes used to prepare the sample.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. application Ser. No. 12/789,831, filed May 28, 2010, which is a continuation of U.S. application Ser. No. 11/582,651, now U.S. Pat. No. 7,727,473, filed Oct. 17, 2006, entitled “CASSETTE FOR SAMPLE PREPARATION,” which claims the benefit of U.S. Provisional Application No. 60/728,569, filed Oct. 19, 2005, entitled “METHOD AND APPARATUS FOR ISOLATING NUCLEIC ACID,” U.S. Provisional Application No. 60/753,622, filed Dec. 22, 2005, entitled “CASSETTE FOR SAMPLE PREPARATION,” and U.S. Provisional Application No. 60/753,618, filed Dec. 22, 2005, entitled “CASSETTE FOR SAMPLE PREPARATION,” each of which is hereby incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    1). Field of the Invention 
         [0003]    The present invention relates to the field of biotechnology devices and, in particular, to devices and methods for preparing samples. 
         [0004]    2). Discussion of Related Art 
         [0005]    DNA can be used to develop new drugs or to link someone to a crime. However, before this can be done, the DNA must be isolated from a sample. These samples include, for example, blood, urine, human cells, hair, bacteria, yeast and tissue. Each of these samples include cells, which include nucleic acid. Nucleic acid is a nucleotide chain, which conveys genetic information. The most common forms of nucleic acid are DNA and RNA. 
         [0006]    In order to isolate the nucleic acid from the samples, prior art devices use a tray having several exposed cavities. The sample is placed into one of the cavities and conventional processing steps are used to isolate the DNA from the sample. 
         [0007]    This prior art system has several disadvantages, including contamination. Since the cavities are exposed, contaminants can easily affect the DNA. In addition, the prior art system requires the preparation of several samples at one time. It is difficult to prepare one or two samples at a time using the prior art devices. 
       SUMMARY 
       [0008]    A cassette for preparing a sample is disclosed herein. The cassette includes at least one mixing chamber for receiving a sample of cells; a first holding chamber; an enzyme in the first holding chamber, the enzyme being transferable into the at least one mixing chamber to break the cells and release nucleic acid from the cells to create bulk material and the nucleic acid in the bulk material; a second holding chamber; magnetic particles in the second holding chamber, the magnetic particles being transferable to the at least one mixing chamber to bind with the nucleic acid; and at least one magnet, positionable to attract the magnetic particles together with the nucleic acid and at least partially separate the nucleic acid from the bulk material in the at least one mixing chamber. 
         [0009]    The mixing chamber has a top surface, the top surface having an opening therein. A removable lid for accessing the opening of the mixing chamber is also provided. The enzyme may be proteinase K. First and second plungers in the first holding chamber and second holding chamber may also be provided, each plunger being movable to transfer the enzyme and magnetic particles, respectively, into the mixing chamber. A thin film that is breakable to transfer the enzyme and magnetic particles through respective ruptures in the thin film into the mixing chamber may also be provided. First and second plungers in the first holding chamber and second holding chamber, each plunger being movable to break the thin film and transfer the enzyme and magnetic particles, respectively into the mixing chamber, may also be provided. A third holding chamber and a lysis solution in the third holding chamber may also be provided, the lysis solution being transferable into the mixing chamber to solubilize the bulk material. A fourth holding chamber and a binding solution in the fourth holding chamber may also be provided, the binding solution being transferable into the mixing chamber to bind the nucleic acid to the magnetic particles. A heating element for heating the mixing chamber may also be provided. 
         [0010]    The cassette may also include a first separation piece having a surface; a first transfer piece having a surface with a cavity therein, the at least one magnet transferring the magnetic particles together with the nucleic acid into the cavity in the surface of the first transfer piece, the first transfer piece being movable relative to the first separation piece so that the magnetic particles together with the nucleic acid move out of the mixing chamber and past the surface of the first separation piece; and a first receiving chamber which receives the magnetic particles and nucleic acid after moving past the surface of the first separation piece. The cassette may further include a second separation piece having a surface; a second transfer piece having a surface with a cavity therein, the second transfer piece being movable relative to the second separation piece so that the magnetic particles together with the nucleic acid move out of the first receiving chamber and past the surface of the second separation piece; and a second receiving chamber which receives the magnetic particles and nucleic acid after moving past the surface of the second separation piece. The cassette may yet further include a third separation piece having a surface; a third transfer piece having a surface with a cavity therein, the third transfer piece being movable relative to the third separation piece so that the magnetic particles together with the nucleic acid move out of the second receiving chamber and past the surface of the third separation piece; and a third receiving chamber which receives the magnetic particles and nucleic acid after moving past the surface of the third separation piece. 
         [0011]    The first receiving chamber may be a washing chamber, and the cassette may further include a washing solution in the washing chamber. The second receiving chamber may be a washing chamber, and the cassette may further include a washing solution in the washing chamber. The third receiving chamber may be an elution chamber, and the cassette may further include an elution buffer in the elution chamber for separating the magnetic particles and the nucleic acid. 
         [0012]    A cassette for preparing a sample is disclosed herein. The cassette includes at least one mixing chamber for receiving a sample of cells, an enzyme being added in the mixing chamber to break the cells and release nucleic acid from the cells to create bulk material and nucleic acid in the bulk material, magnetic particles being added to the mixing chamber to bind with the nucleic acid; a first separation piece having a surface; a first transfer piece having a surface with a cavity therein; a magnet, positionable to attract the magnetic particles together with the nucleic acid and at least partially separate the nucleic acid from the bulk material in the at least one mixing chamber and to transfer the magnetic particles together with the nucleic acid into the cavity in the surface of the first transfer piece, the first transfer piece being movable relative to the first separation piece so that the magnetic particles together with the nucleic acid move out of the mixing chamber and past the surface of the first separation piece; and a first receiving chamber which receives the magnetic particles and nucleic acid after moving past the surface of the first separation piece. 
         [0013]    The second piece may be rotatable relative to the first piece. The first receiving chamber may be a washing chamber, and the cassette may further include a washing solution in the washing chamber. The cassette may also include an elution chamber, and an elution buffer in the elution chamber for separating the magnetic particles and the nucleic acid. The cassette may also include a second separation piece having a surface, a second transfer piece having a surface with a cavity therein, the second transfer piece being movable relative to the second separation piece so that the magnetic particles together with the nucleic acid move out of the first receiving chamber and past the surface of the second separation piece, the elution chamber receiving the magnetic particles and nucleic acid after moving past the surface of the first separation piece. The second transfer piece may be movable relative to the second separation piece so that the magnetic particles move out of the elution chamber, leaving the nucleic acid in the elution chamber. 
         [0014]    The secondary chamber may be an elution chamber and the cassette may further include an elution buffer in the elution chamber for separating the magnetic particles and the nucleic acid. The cassette may also include a second separation piece having a surface, a second transfer piece having a surface with a cavity therein, the second transfer piece being movable relative to the second separation piece so that the magnetic particles together with the nucleic acid move out of the first receiving chamber and past the surface of the second separation piece, and a second receiving chamber which receives the magnetic particles and nucleic acid after moving past the surface of the second separation piece. The cassette may further include a third separation piece having a surface, a third transfer piece having a surface with a cavity therein, the third transfer piece being movable relative to the third separation piece so that the magnetic particles together with the nucleic acid move out of the second receiving chamber and past the surface of the third separation piece, and a third receiving chamber which receives the magnetic particles and nucleic acid after moving past the surface of the third separation piece. The second receiving chamber may be a washing chamber, and the cassette may further include a washing solution in the washing chamber. The third receiving chamber may be an elution chamber, and the cassette may further include an elution buffer in the elution chamber for separating the magnetic particles and the nucleic acid. 
         [0015]    A cassette for preparing samples is disclosed herein. The cassette includes an enclosure, the enclosure comprising a mixing chamber, the mixing chamber including an opening for receiving a sample of cells having nucleic acid; a plurality of holding chambers having contents, the contents of one of the plurality of holding chambers comprising magnetic particles, and the contents of one of the plurality of holding chambers comprising a proteinase K solution; a plurality of plungers, each of the plurality of plungers corresponding to one of the plurality of holding chambers, for transferring the contents of the plurality of holding chambers into the mixing chamber, the proteinase K solution breaking up the cells to release the nucleic acid and the nucleic acid binding to the magnetic particles in the mixing chamber; a first valve, coupled to the mixing chamber, the first valve including a positionable magnet for attracting the magnetic particles; a washing chamber, coupled to the first valve; a second valve, coupled to the first washing chamber, the second valve including a positionable magnet for attracting the magnetic particles; and an elution chamber, coupled to the second valve, the elution chamber including an opening for removing the nucleic acid from the elution chamber. 
         [0016]    One of the plurality of holding chambers may include a binding solution and one of the plurality of holding chambers may include a lysis solution, and wherein one of the plurality of plungers may transfer the binding solution into the mixing chamber and wherein one of the plurality of plungers may transfer the lysis solution into the mixing chamber. 
         [0017]    A cassette for preparing a sample is disclosed herein. The cassette includes a reaction chamber for receiving a sample of cells; a first holding chamber; an enzyme in the first holding chamber, the enzyme being transferable into the reaction chamber to break the cells and release nucleic acid from the cells to create bulk material and the nucleic acid in the bulk material; a particle chamber; particles to bind with the nucleic acid in the particle chamber; a second holding chamber; an elution buffer in the second holding chamber to release the nucleic acid from the particles; and an elution chamber for receiving the elution buffer and the released nucleic acid, wherein the elution buffer is transferable from the holding chamber to the reaction chamber, through the particle chamber, and into the elution chamber. 
         [0018]    The cassette may include a third holding chamber and a lysis solution in the third holding chamber, the lysis solution being transferable into the reaction chamber to solubilize the bulk material. 
         [0019]    The cassette may include a fourth holding chamber and a binding solution in the fourth holding chamber, the binding solution being transferable into the reaction chamber to bind the nucleic acid to the particles. 
         [0020]    The reaction chamber may be aligned with the particle chamber and the elution chamber may be alignable with the particle chamber. 
         [0021]    The cassette may include a waste chamber for receiving the enzyme and bulk material. 
         [0022]    The cassette may include a plunger to transfer the contents of the reaction chamber through the particle chamber and into the waste chamber. 
         [0023]    The cassette may include a plunger to transfer the contents of the reaction chamber through the particle chamber and into the elution chamber. 
         [0024]    The cassette may include a valve in each of the first and second holding chambers to transfer the contents of each of the first and second holding chambers into the reaction chamber. 
         [0025]    The valve may include a plunger to transfer the contents from the valve into the reaction chamber. 
         [0026]    Another cassette for preparing samples is also disclosed herein. The cassette includes an enclosure, the enclosure including a reaction chamber, the reaction chamber including an opening for receiving a sample of cells having nucleic acid; a plurality of holding chambers; an enzyme in one of the plurality of holding chambers; a lysis buffer in one of the plurality of holding chambers; a binding buffer in one of the plurality of holding chambers; an elution buffer in one of the plurality of holding chambers; a particle chamber; particles in the particle chamber, the particles to releasably bind with the nucleic acid; and an elution chamber to receive the released nucleic acid, the elution chamber including an opening for removing the nucleic acid from the enclosure. 
         [0027]    The enclosure may include a waste chamber. 
         [0028]    Each of the plurality of holding chambers may include a plunger for transferring contents of the plurality of holding chambers to the reaction chamber. 
         [0029]    The cassette may include one or more washing buffers in one or more of the plurality of holding chambers. 
         [0030]    The reaction chamber may be aligned with the particle chamber and wherein the elution chamber may be alignable with the particle chamber. 
         [0031]    A further cassette for preparing a sample is also disclosed herein. The cassette includes a reaction chamber for receiving a sample of cells; a first holding chamber; an enzyme in the first holding chamber, the enzyme being transferable into the reaction chamber to break the cells and release nucleic acid from the cells to create bulk material and the nucleic acid in the bulk material; a particle chamber; particles to bind with the nucleic acid in the particle chamber; a second holding chamber; an elution buffer in the second holding chamber to release the nucleic acid from the particles; and an elution chamber for receiving the elution buffer and the released nucleic acid, wherein each of the holding chambers comprises an outer housing having a first chamber therein and at least one opening, the first chamber receiving a valve, the valve comprising: an inner housing having a second chamber therein and at least one opening, the inner housing rotatable relative to the outer housing/the at least one opening of the inner housing alignable with the at least one opening of the outer housing, the second chamber having contents; and a plunger in the second chamber to transfer the contents of the second chamber through the at least one opening of the inner housing and the at least one opening of the outer housing when the at least one opening of the inner housing and the at least one opening of the outer housing are aligned. 
         [0032]    The cassette may include a third holding chamber and a lysis solution in the third holding chamber, the lysis solution being transferable into the reaction chamber to solubilize the bulk material. 
         [0033]    The cassette may include a fourth holding chamber and a binding solution in the fourth holding chamber, the binding solution being transferable into the reaction chamber to bind the nucleic acid to the particles. 
         [0034]    The cassette may include a waste chamber for receiving the enzyme and bulk material. 
         [0035]    The cassette may include a plunger to transfer the contents of the reaction chamber through the particle chamber and into the waste chamber. 
         [0036]    The cassette may include a plunger to transfer the contents of the reaction chamber through the particle chamber and into the elution chamber. 
         [0037]    The reaction chamber may be aligned with the particle chamber and wherein the elution chamber may be alignable with the particle chamber. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0038]    The invention is described by way of example with reference to the accompanying drawings, wherein: 
           [0039]      FIG. 1  is a cross-sectional side view of a cassette for preparing samples according to an embodiment of the invention; 
           [0040]      FIG. 2  is a perspective view of a cassette for preparing samples according to an embodiment of the invention; 
           [0041]      FIG. 3  is a cross-sectional side view showing a sample being placed into the cassette using a pipette, according to an embodiment of the invention; 
           [0042]      FIG. 4  is a perspective view of a magazine, in which the cassette of  FIG. 1  is used, according to an embodiment of the invention; 
           [0043]      FIG. 5  is a perspective view of an instrument, in which the magazine of  FIG. 4  is used, according to an embodiment of the invention; 
           [0044]      FIG. 6  is a cross-sectional side view of the cassette of  FIG. 1 , showing the transfer of a PK solution into a mixing chamber, according to an embodiment of the invention; 
           [0045]      FIG. 7  is a cross-sectional side view of the cassette of  FIG. 1 , showing the transfer of a lysis solution into a mixing chamber, according to an embodiment of the invention; 
           [0046]      FIG. 8  is a cross-sectional side view of the cassette of  FIG. 1 , showing the transfer of a binding solution into a mixing chamber, according to an embodiment of the invention; 
           [0047]      FIG. 9  is a cross-sectional side view of the cassette of  FIG. 1 , showing the transfer of metallic beads into the mixing chamber, according to an embodiment of the invention; 
           [0048]      FIG. 10  is a cross-sectional side view of the cassette of  FIG. 1 , showing metallic beads bound to a first valve, according to an embodiment of the invention; 
           [0049]      FIG. 11  is a cross-sectional side view of the cassette of  FIG. 1 , showing the transfer of metallic beads from a mixing chamber to a washing chamber, according to an embodiment of the invention; 
           [0050]      FIG. 12  is a perspective end view of a valve for use in the cassette of  FIG. 1  according to an embodiment of the invention; 
           [0051]      FIG. 13  is a cross-sectional side view of the cassette of  FIG. 1 , showing metallic beads bound to a second valve, according to an embodiment of the invention; 
           [0052]      FIG. 14  is a cross-sectional side view of the cassette of  FIG. 1 , showing the transfer of metallic beads from a first washing chamber to a second washing chamber, according to an embodiment of the invention; 
           [0053]      FIG. 15  is a cross-sectional side view of the cassette of  FIG. 1 , showing metallic beads bound to a third valve, according to an embodiment of the invention; 
           [0054]      FIG. 16  is a cross-sectional side view of the cassette of  FIG. 1 , showing the transfer of metallic beads from a second washing chamber to an elution chamber, according to an embodiment of the invention; 
           [0055]      FIG. 17  is a cross-sectional side view of the cassette of  FIG. 1 , showing transfer of metallic beads from an elution chamber to a second washing chamber, according to an embodiment of the invention; 
           [0056]      FIG. 18  is a cross-sectional side view of the cassette of  FIG. 1 , showing removal of a prepared sample from an elution chamber, according to an embodiment of the invention; 
           [0057]      FIG. 19  is a perspective view of a magazine in which a multi-channel pipette is used to access a plurality of samples from a plurality of cassettes; 
           [0058]      FIG. 20  is a cross-sectional perspective view of an alternative embodiment of the cassette of  FIG. 1  according to an embodiment of the invention; 
           [0059]      FIG. 21  is a detailed perspective view of an assembly component of the cassette of  FIG. 20  according to an embodiment of the invention; 
           [0060]      FIG. 22  is a detailed perspective view of a plunger of the cassette of  FIG. 20  according to an embodiment of the invention; 
           [0061]      FIG. 23  is a detailed perspective view of a valve of the cassette according to an embodiment of the invention; and 
           [0062]      FIG. 24  is a detailed perspective view of the valve of  FIG. 23  according to an embodiment of the invention. 
           [0063]      FIG. 25  is a perspective view of a cassette for preparing samples according to one embodiment of the invention; 
           [0064]      FIG. 26  is a partial cross-sectional view of the cassette of  FIG. 25 ; 
           [0065]      FIG. 27  is a partial cross-sectional perspective view of a valve for use in the cassette of  FIG. 25 ; 
           [0066]      FIG. 28  is a partial cross-sectional side view of the valve of  FIG. 25 ; 
           [0067]      FIG. 29  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing the addition of a sample into a mixing chamber, according to an embodiment of the invention; 
           [0068]      FIG. 30  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing the transfer of a PK solution into a mixing chamber, according to an embodiment of the invention; 
           [0069]      FIG. 31  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing the transfer of a lysis solution into a mixing chamber, according to an embodiment of the invention; 
           [0070]      FIG. 32  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing the transfer of a binding solution into a mixing chamber, according to an embodiment of the invention; 
           [0071]      FIG. 33  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing transfer of a sample through particles and into a waste chamber, according to an embodiment of the invention; 
           [0072]      FIG. 34  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing the pumping of a wash buffer into the mixing chamber, according to an embodiment of the invention; 
           [0073]      FIG. 35  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing the pumping of the wash buffer through the particles, according to an embodiment of the invention; 
           [0074]      FIG. 36  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing the pumping of a second wash buffer into the mixing chamber, according to an embodiment of the invention; 
           [0075]      FIG. 37  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing the pumping of the second wash buffer through the particles, according to an embodiment of the invention; 
           [0076]      FIG. 38  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing the pumping of an elution buffer into the mixing chamber, according to an embodiment of the invention; 
           [0077]      FIG. 39  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing the pumping of the elution buffer through the particles and into the elution chamber, according to an embodiment of the invention; and 
           [0078]      FIG. 40  is a cross-sectional perspective view of the cassette of  FIG. 25 , showing the removal of the sample from the elution chamber, according to an embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0079]      FIG. 1  illustrates a cassette  10 , which can be used to prepare cell samples. The cassette  10  includes a housing  12 , a mixing chamber  14 , first, second third and fourth holding chambers  16 ,  18 , 20  and  22 , first, second, third and fourth plungers  24 , 26 , 28  and  30 , first, second and third valves  32 ,  34  and  36 , first and second washing chambers  38  and  40 , an elution chamber  42 , first, second, third and fourth pumps  44 ,  46 ,  48  and  50 , first and second lids  52  and  54 , first and second heating elements  56  and  58  and a magnet  60 . 
         [0080]    Each of the chambers  14 ,  16 ,  18 ,  20 ,  22 ,  38 ,  40  and  42 , plungers  24 ,  26 ,  28  and  30 , valves  32 ,  34  and  36 , pumps  44 ,  46 ,  48  and  50 , and heating elements  56  and  58  are enclosed within the housing. The lids  52  and  54  are movably attached to the housing  12 . The magnet  60  is removably positionable in the first valve  32 , second valve  34  and third valve  36 . 
         [0081]    The mixing chamber  14  has a top surface  62 , a bottom surface  64  and opposing side surfaces  66 ,  68 . The top surface  62  of the mixing chamber includes an opening  70  therein. 
         [0082]    The first lid  52  is configured to provide access to the opening  70  in the top surface  62  of the mixing chamber. The first lid  52  and the opening  70  are coaxial. The first lid  52  is shown being movably attached to the housing  12 , such that when the lid  52  is open or off, the opening  70  is accessible and if the lid  52  is closed or on, the opening  70  is not accessible. 
         [0083]    A thin film  74  forms one wall of the mixing chamber  14 . The thin film  74  is breakable, such that the mixing chamber  14  is accessible when the thin film  74  has been broken or ruptured. 
         [0084]    The first holding chamber  16 , second holding chamber  18 , third holding chamber  20  and fourth holding chamber  22  are shown located next to the mixing chamber  14  and aligned vertically with one another. Each of the holding chambers  16 ,  18 , 20 ,  22  has an opening  76  next to the thin film  74  of the mixing chamber  14 . 
         [0085]    The cassette  10  further includes magnetic iron particles in the form of magnetic iron beads in the first holding chamber  16 . The cassette  10  further includes a binding solution in the second holding chamber  18 . The cassette  10  further includes a lysis solution in the third holding chamber  20 . The cassette  10  further includes a proteinase K (PK) solution in the fourth holding chamber  22 . 
         [0086]    The first, second, third and fourth plungers  24 ,  26 ,  28  and  30  are located in the first, second, third and fourth holding chambers  16 ,  18 ,  20  and  22 , respectively. 
         [0087]    Each of the plungers  16 ,  18 , 20 , 22  includes a base  78 , a shaft  80  and a piercing element  82 . The shaft  80  extends from the base  78 . The piercing element  82  is at the end of the shaft  80  opposing the base  78  and is pointed. The piercing element  82  is configured to break or rupture the thin film  74  of the mixing chamber  14 . 
         [0088]    The first pump  44  is a bellows pump having a pumping portion and a nozzle portion. The nozzle portion of the first pump  44  is located inside the mixing chamber  14 . The pumping portion of the first pump  44  is located outside the mixing chamber, such that the pumping portion is actuatable. 
         [0089]    A heating element  56  is provided at the bottom surface  64  of the mixing chamber  14  for heating the contents of the mixing chamber  14 . The heating element  56  may be a variable heating element. 
         [0090]    The opposing side surface  68  of the mixing chamber  14  also includes an opening  84 . A first valve  32  is provided between the opening  84  in the side  68  of the mixing chamber  14  and the first washing chamber  38 . 
         [0091]    The first valve  32  has a first stationary piece  86  and a second movable piece  88 , the second piece  88  being movable relative to the first piece  86 . The first stationary piece  86  includes a first opening  90  and a second opening  92  and has a surface  94 . The second piece  88  has an opening  94  therein for receiving the magnet  60 . The second piece  88  has a surface  96  with a cavity  98  therein. The magnet  60  is shaped to correspond to the opening  94  in the second piece  88 . The magnet  60  is movable in the opening  94  of the second piece  88 , and is removable from the second piece  88 . 
         [0092]    The cassette  10  includes a washing solution in the first washing chamber  38 . The second pump  46  is also a bellows pump, and the nozzle portion of the second pump  46  is located in the first washing chamber  38 . 
         [0093]    The second valve  34  is provided between the first washing chamber  38  and the second washing chamber  40 . The second valve  34  is structurally and functionally the same as the first valve  43 , and also includes a first stationary piece  86  and a second movable piece  88 . The first stationary piece  86  includes a first opening  90  and a second opening  92  and has a surface  94 . The second movable piece  88  has a surface  96  with a cavity  98  therein. 
         [0094]    The cassette  10  includes a washing solution in the second washing chamber  40 . The third pump  48  is also a bellows pump, and the nozzle portion of the third pump  48  is located in the second washing chamber  40 . 
         [0095]    The third valve  36  is provided between the second washing chamber  40  and the elution chamber  42 . The third valve  36  is structurally and functionally the same as the first valve  32  and the second valve  34 , and also includes a first stationary piece  86  and a second movable piece  88 . The first stationary piece  86  includes a first opening  90  and a second opening  92  and has a surface  94 . The second movable piece  88  has a surface  96  with a cavity  98  therein. 
         [0096]    The cassette  10  includes a washing solution in the elution chamber  42 . The fourth pump  50  is also a bellows pump, and the nozzle portion of the fourth pump  50  is located in the elution chamber  42 . 
         [0097]    A heating element  58  is provided at the bottom surface of the elution chamber  42  for heating the contents of the elution chamber  42 . The heating element  58  may be a variable heating element. 
         [0098]    The elution chamber  42  includes an opening  100  at its top surface for accessing the contents of the elution chamber  42 . 
         [0099]    The second lid  54  is configured to provide access to the opening  100  in the top surface of the elution chamber  42 . The second lid  54  is coaxial with the opening  100 . The second lid  54  is shown being movably attached to the housing  12 , such that when the lid  54  is open or off, the opening  100  is accessible and if the lid  54  is closed or on, the opening  100  is not accessible. 
         [0100]    With reference to  FIG. 2 , as described above, the cassette  10  includes a housing  12 . The housing  12  includes a first assembly component  102 , a second assembly component  104  and a third assembly component  106 . 
         [0101]    The first assembly component  102  includes the mixing chamber  14 , the washing chambers  38  and  40 , the elution chamber  42  and the first stationary piece  86  of each of the valves  32 ,  34  and  36 . The first assembly component  102  also includes attachment parts  108 ,  110  (see  FIG. 1 ) at one of its ends and an attachment piece  112  (see  FIG. 1 ). 
         [0102]    The second assembly component  104  includes the holding chambers  16 ,  18 ,  20  and  22  and an opening for receiving the first pump  44 . The second assembly component  104  also includes attachment receiving parts  114 ,  116  (see  FIG. 1 ). 
         [0103]    The third assembly component  106  includes openings for receiving the second, third and fourth pumps  46 ,  48  and  50 , respectively, and includes lids  52  and  54 . 
         [0104]    The cassette  10  is assembled by inserting the attachment components  108 ,  110  of the first assembly component  102  into the attachment receiving components  114 , 116  of the second assembly component  104 , respectively. The third assembly component  106  is then secured to the first assembly component using the attachment piece  112 , thereby forming the assembled cassette  10 , as illustrated in  FIG. 2 . The plungers  24 ,  26 ,  28  and  30 , pumps  44 ,  46 ,  48  and  50 , and the second movable piece  88  of each of the valves  32 ,  34  and  36 , are inserted into the cassette  10 . 
         [0105]    In use, as shown in  FIG. 3 , the first lid  52  is removed to provide access to the opening  70  of the mixing chamber  14 . A sample of cells is placed into an assembled cassette  10  using a pipette  118 . The cells in the sample include nucleic acid. The pipette  118  having the sample therein is placed in the mixing chamber  14 . The sample is released from the pipette  118 . 
         [0106]    As shown in  FIG. 4 , the cassette  10  is closed by closing the first lid  52 . The cassette  10  is then placed together with similar cassettes  10  into a magazine  120 , or rack, for containing a series of cassettes  10 . 
         [0107]    As shown in  FIG. 5 , the magazine  120  is placed into an instrument  122 . A protocol may be selected for preparing the sample in the cassette  10  in the instrument  122 . 
         [0108]    As shown in  FIG. 6 , the PK solution is added to the sample. The PK solution is added by moving the plunger  30  in the fourth holding chamber  22 . A force is applied to the base  78  of the plunger  30  to move the plunger  30 . As the piercing element  82  of the plunger  30  advances toward the mixing chamber  14 , the piercing element  82  punctures and ruptures the thin film  74 . The break in the thin film  74  provides access to the mixing chamber  14 . Continued motion of the plunger  30  transfers the contents (e.g., PK solution) of the first holding chamber  22  into the mixing chamber  14 . 
         [0109]    The PK solution is mixed with the sample by pumping the mixture with the first pump  44 . The PK solution destroys the walls of the cells of the sample, creating bulk material and nucleic acid in the bulk material. 
         [0110]    As shown in  FIG. 7 , the lysis solution is added to the sample. Plunger  28  operates in the same manner as plunger  30  to transfer the lysis solution in the third holding chamber  20  into the mixing chamber  14 . The sample is pumped to mix the lysis buffer with the PK solution and sample of cells. The lysis solution is typically a salt or detergent. The lysis solution is used to solubilize the bulk material. The lysis solution typically does not solubilize proteins. 
         [0111]    The heating element  56  may be used to heat the lysis solution and sample. The heating element  56  may be controlled by the instrument  122 . As described hereinabove, the temperature of the heating element  56  may be variable, and is selected to optimize the effectiveness of the lysis solution. 
         [0112]    As shown in  FIG. 8 , the binding solution is added to the sample, PK solution and lysis buffer solution. Plunger  26  operates in the same manner as plunger  30  to transfer the binding solution in the second holding chamber  18  into the mixing chamber  14 . The solution is pumped to mix the binding solution with the PK solution, lysis solution and sample. The binding solution is typically hydrophobic and increases salt in the solution. The binding solution causes the nucleic acid to be magnetically charged. 
         [0113]    As shown in  FIG. 9 , the magnetic beads are added to the solution and pumped for about two minutes. Plunger  24  operates in the same manner as plunger  30  to transfer the lysis solution in the first holding chamber  18  into the mixing chamber  14 . The magnetic beads bind to the magnetically charged nucleic acid. 
         [0114]    As shown in  FIG. 10 , the magnetic beads, together with the nucleic acid, are bound to the first valve  32 . The removable positionable magnet  60  is placed in the first valve  32  and slid to a position in the first valve  32  to attract the magnetic beads, which are bound to the nucleic acid, from the mixing chamber  14  to the first valve  32 . 
         [0115]    As shown in  FIG. 11 , the magnetic beads, together with the nucleic acid, are then moved from the mixing chamber  14  and received in the first washing chamber  38 . 
         [0116]      FIG. 12  is a detailed view of the valves  32 ,  34 ,  36  illustrating the movement of the magnetic beads from the mixing chamber  14  to the first washing chamber  38 . As discussed above each of the valves  32 ,  34  and  36  include a first stationary piece  86  and a second movable piece  88 , the second piece  88  being movable relative to the first piece  86 . 
         [0117]    The magnet  60  is inserted into the opening  94  of the second piece  88 . The magnet  60  is inserted to a position corresponding to the openings  90  and  92  of the first piece  86 . The magnet  60  attracts the magnetic beads from the mixing chamber  14  through the opening  90  in the first piece  86  and into the cavity  98  in the second piece  88 . The second piece  88  is rotated such that the magnetic beads are sealed in the cavity  98  of the second piece  88 , between surfaces of the second piece  88  and the first piece  86 . The second piece  88  is rotated past the surface  94  of the first piece  86 , such that the cavity  98  is accessible in the opening  92  of the first piece  86 . The magnet  60  is then removed from the opening  94  in the second piece  88  to release the magnetic beads from the cavity  98  in the second piece  88 . 
         [0118]    As shown in  FIG. 13 , the magnetic beads and nucleic acid are then washed with the washing solution by pumping the solution with the second pump  46 . The magnetic beads, together with the nucleic acid, are then bound to the second valve  34  by inserting the magnet  60  into the second valve  34 , as described above with reference to  FIG. 12 . 
         [0119]    As shown in  FIG. 14 , the magnetic beads, together with the nucleic acid, are then moved from the first washing chamber  38  to the second washing chamber  40  using the second valve  34 . The second valve  34  transfers the magnetic beads and nucleic acid from the first washing chamber  38  to the second washing chamber  40 , as described above with reference to  FIG. 12 . 
         [0120]    As shown in  FIG. 15 , the magnetic beads and nucleic acid are then washed with the washing solution a second time by pumping the solution with the third pump  48 . The magnetic beads, together with the nucleic acid, are then bound to the third valve  36  by positioning the magnet  60  in the third valve  36 , as described above with reference to  FIG. 12 . 
         [0121]    As shown in  FIG. 16 , the magnetic beads and nucleic acid are then moved from the second washing chamber  40  to the elution chamber  42 . The magnetic beads and nucleic acid are transferred from the second washing chamber  40  to the elution chamber  42  using the procedure described above with reference to  FIG. 12 . 
         [0122]    An elution buffer solution is then mixed with the magnetic beads and nucleic acid by pumping the solution with the fourth pump  50 . The heating element  58  may be used to heat the elution buffer, magnetic beads and nucleic acid. The heating element  58  may be controlled by the instrument  122 . The temperature may be variable and may be selected to optimize release of the nucleic acid from the magnetic beads. 
         [0123]    The magnetic beads alone are then bound again to the third valve  36  by positioning the magnet  60  in the third valve  36  as described above with reference to  FIG. 12 . 
         [0124]    As shown in  FIG. 17 , the magnetic beads alone are then moved from the elution chamber  42  back into the second washing chamber  40 , leaving the nucleic acid in the elution chamber  42 . The magnetic beads are transferred from the elution chamber  42  to the second washing chamber  40  using the procedure described above with reference to  FIG. 12 . 
         [0125]    As shown in  FIG. 18 , the prepared sample of nucleic acid may be accessed using a second pipette  124 . The second lid  54  is removed to provide access to the opening  100  in the elution chamber  42 . The pipette  124  is inserted into the opening  100  and the prepared sample of nucleic acid is withdrawn. 
         [0126]    As shown in  FIG. 19 , a multi-channel pipette  126  may be used to access a plurality of samples from a plurality of cassettes  10 . 
         [0127]      FIG. 20  illustrates an alternative embodiment of the cassette  10 . The cassette  10   a  illustrated in  FIG. 20  differs from the cassette  10  illustrated in  FIG. 1  in that the assembly component  104   a  includes a seal  130 , the plungers  24   a,    26   a,    28   a  and  30   a  each include seals  132 ,  134 ,  136  and  138 , respectively, and the valves  32   a,    34   a  and  36   a  have a different arrangement, as discussed hereinafter. 
         [0128]      FIG. 21  illustrates the assembly component  104   a  in more detail. The assembly component  104   a  includes a seal  130 . The illustrated seal  130  is a double elastomer, which extends along the circumference of the assembly component  104   a.    
         [0129]      FIG. 22  illustrates the plunger  24   a  in more detail. The plunger  24   a  includes a seal  132 . The illustrated seal  132  is also a double elastomer, which extends along the circumference of the plunger  24   a.  It will be appreciated that each of plungers  26   a,    28   a  and  30   a  may also have a similar arrangement. 
         [0130]      FIGS. 23 and 24  illustrate the valve  32   a  in more detail. It will be appreciated that valves  34   a  and  36   a  also have a similar arrangement. The valve  32   a  includes a magnet  60   a,  a housing  142 , and a shaft  144 . The housing  142  includes a first opening (not shown) to receive the magnet  60   a  and a second opening  148  to expose the magnet  60   a  and receive the particles  146 . The magnet  60   a  is shaped to correspond to the opening  148  and is selected to attract the particles  146 . The housing  142  also includes a third opening (not shown) for receiving the shaft  144 . As shown in  FIG. 24 , the shaft  144  may include a keyed element  150 . The keyed element  150  is shaped to engage the cassette  10   a.  It will be appreciated that the shaft may be removable or an integrated element of the valve  32   a.  It will also be appreciated that the housing  142  may, alternatively, include the keyed element. 
         [0131]    The shaft  144  is engageable with the housing  142  and magnet  60   a  to rotate the housing  142  and magnet  60   a  relative to the cassette  10   a  to move the particles  146  from the mixing chamber  14   a  to the washing chamber  38   a.  It will be appreciated that valves  34   a  and  36   a  operate in a similar manner to transfer the particles  146  from the washing chamber  38   a  to the washing chamber  40   a  and from the washing chamber  40   a  to the elution chamber  42   a,  respectively. 
         [0132]    In one embodiment, a total of about 200 μL sample is placed into the cassette. The sample is mixed with a total of about 50 μL of the PK solution by pumping the mixture of the sample and PK solution for about one minute. A total of about 200 μL of the lysis solution is added to the sample and PK solution, and the solutions are pumped for about one minute to mix the solutions. The mixture is then heated at about 60° C. for about ten minutes, and the mixture is allowed to cool for about 5 minutes. The mixture is further pumped while it cools. A total of about 500 μL of binding solution is added to the mixture. The solutions are pumped for about one minute. The magnetic beads are added to the solution and pumped for about two minutes. The magnetic beads are transferred and washed as described above. A total of about 700 μL of washing solution is provided in each of the washing chambers. A total of about 200 μL of elution solution is provided in the elution chamber. The magnetic beads are mixed with the elution solution by pumping the mixture for about one minute. The mixture is then heated at about 90° C. for about two minutes. The process continues as previously described. 
         [0133]    Although the cassette  10  has been described as having a mixing chamber  14 , two washing chambers  38  and  40  and an elution chamber  42 , it is envisioned that only one washing chamber or no washing chamber may alternatively be provided. 
         [0134]    Although the cassette has been described as using a single removable magnet  60 , it is envisioned that each valve may include a positionable magnet, such that the magnet does not need to be removed. The magnet  60  may be rotatable, and used to rotate the second piece of the valves. Alternatively, the magnet may only slide inside of each of the valves, and the second piece is rotated independent of the magnet. 
         [0135]    It is envisioned that a cassette  10  that does not use valves as described herein may be used to transfer the magnetic particles from the mixing chamber to the elution chamber. In such an embodiment, a slideable magnet may be provided to transfer the magnetic particles from one chamber to the next. 
         [0136]    Although the cassette  10  has been described as using a PK solution, lysis solution, binding solution and magnetic beads to release the nucleic acid and magnetic beads, it is envisioned that it may be possible to practice the invention without using each of the above solutions. In addition, although the solution was described as using a PK solution to break up the cells, it is envisioned that any enzyme which causes cells to break up to release nucleic acid may be used with the invention. 
         [0137]    It is envisioned that the housing  12  may be transparent, such that the procedure can be viewed. 
         [0138]    In one embodiment the thin film  74  is a lamination. 
         [0139]    In one embodiment, the lids  52  and  54  may be screw-top lids. In one embodiment, the lids  52 ,  54  include a hydrophobic membrane, which allows gasses to vent through the lid, but does not allow the liquids to escape the cassette  100 . 
         [0140]    In one embodiment, pump  50  is insertable into opening  100 . In one embodiment, pump  50  can also be used as a pipette to remove the sample from the cassette  10 . 
         [0141]    It is also envisioned that the mixing chamber  14  may be provided without a puncturable thin film  74 . In such an embodiment, the plungers  24 ,  26 ,  28  and  30  would not need a piercing element  82 . Instead, the plungers  24 ,  26 ,  28  and  30  would have a sealing element to prevent leakage of the contents of the holding chamber  16 ,  18 ,  20  and  22 , associated with each plunger  24 ,  26 ,  28  and  30 , respectively, until the plunger was moved. 
         [0142]      FIG. 25  illustrates a cassette  200 , which can be used to prepare cell samples. The cassette  200  includes a housing  202 , first, second, third, fourth, fifth, sixth, seventh and eighth holding chambers  204   a - h,  respectively. Each of the holding chambers  204   a - h  includes a valve assembly  206   a - h  therein. A locking element  207  may also be provided. 
         [0143]      FIG. 26  illustrates the cassette  200  in more detail. The cassette  200  further includes a reaction chamber  208 , a particle chamber  210 , a waste chamber  212 , a waste overflow chamber  214 , an elution chamber  216 , a plunger  218 , and first and second lids  220  and  222 , respectively. The cassette  200  may also include one or more heating elements (not shown). 
         [0144]    Each of the holding chambers  204   a - h,  valve assemblies  206   a - h,  reaction chamber  208 , particle chamber  210 , waster chamber  212 , waster overflow chamber  214 , and plunger  218  are enclosed within the housing  202 . The lids  222 ,  224  are movably or removably attached to the housing  202 . 
         [0145]    The reaction chamber  208  has a top surface  226 , a bottom surface  228  and opposing side surfaces  230 ,  232 . 
         [0146]    The top surface  226  of the reaction chamber  208  includes an opening  234  therein. The first lid  222  is configured to provide access to the opening  234  in the top surface  226  of the reaction chamber  208 . The illustrated lid  222  is a screw-top lid; however, any other lid which (removably) provides access to the opening  234 . 
         [0147]    The bottom surface  228  of the reaction chamber  208  includes an opening  236  therein. The opening  236  allows the reaction chamber  208  to be in fluid communication with the particle chamber  210 . 
         [0148]    The side surface  232  includes openings  238   a - h  therein. The openings  238   ah  allow the reaction chamber  208  to be in fluid communication with the holding chambers  204   a - h,  respectively. 
         [0149]    The cassette  200  includes a binding solution in a holding chamber  204   a.  The cassette  200  further includes a lysis solution in a holding chamber  204   b.  The cassette  200  further includes a proteinase K (PK) solution in a holding chamber  204   c.  The cassette  200  further includes a washing solution in one or more of the holding chambers  204   d - e.  The cassette  200  further includes an elution solution in a holding chamber  204   f.    
         [0150]    The plunger  218  and the first lid  222  are shown attached to one another to form an integral plunging system. The plunger  218  is compressible to pump the contents of the reaction chamber  208 . Alternatively, a separate pump may also be provided to pump the contents of the reaction chamber  208 . The plunger  218  is also movable within the reaction chamber  208  to push the contents of the reaction chamber  208  through the particle chamber  210 . 
         [0151]    The holding chambers  204   a - h  are formed in the housing  202  of the cassette  200 . Each of the holding chambers  204   a - h  include a guide  240   a - h  engageable with a corresponding slot in the valve assembly  206 . The holding chambers  204   a - h  also include at least one opening  242   a - h,  engageable with corresponding openings in the valve assembly  206   a - h.  The housing  202  also includes slots  244   a - h,  engageable with corresponding guides in the valve assembly  206   a - h.    
         [0152]    The particle chamber  210  includes a body  250 , having a first opening  252 , a second opening  254 , and a plurality of particles  256  thereon. The particles may be magnetic or nonmagnetic, depending on the application of the cassette  200 . The particles may be, for example, cellulose, plastic or iron. The particle chamber  210  is shown aligned with the reaction chamber  208 . 
         [0153]    The waste chamber  212  and the elution chamber  216  are integrated with one another and are rotatable relative to the housing  202 . The waste overflow chamber  214  is positioned near the waste chamber  212  and is capable of being in fluid communication with the waste chamber  212 . The waste chamber  212  and elution chamber  216  are alignable with the particle chamber and are capable of being in fluid communication with the particle chamber  210 . 
         [0154]    The waste chamber  212  has a top surface  270 , a bottom surface  272 , an inner surface  274  and an outer surface  276 . The overflow waste chamber  214  has a top surface  278 , a bottom surface  280  and opposing side surfaces  282 ,  284 . The elution chamber  216  also has a top surface  286 , a bottom surface  288 , an inner surface  290  and an outer surface  292 . 
         [0155]    It will be appreciated that the outer surface  276  of the waste chamber  212  and the outer surface  292  of the elution chamber  216  are integrated with one another. It will also be appreciated that the inner surface  274  of the waste chamber  212  is the same as the inner surface  290  of the elution chamber  216 . 
         [0156]    The top surface  270  of the waste chamber  212  and the top surface  286  of the elution chamber  216  each have an opening  294 ,  296 , respectively. These openings  294 , 296  are alignable with the opening  252  in the particle chamber  210  to provide a fluid communication route between the particle chamber  210  and the waste chamber  212  and the elution chamber  216 . 
         [0157]    The outer surface  276  of the waste chamber  212  includes an opening  298  therein. One of the side surfaces  282 , 284  of the overflow waste chamber  214  includes an opening  300  therein. The opening  298  and opening  300  are alignable, such that fluid flowing into the waste chamber  212  can flow from the waste chamber  212  and into the overflow waste chamber  214 . 
         [0158]    The bottom surface  288  of the elution chamber  216  includes an opening  302  therein. The second lid  224  is configured to provide access to the opening  302  in the bottom surface  288  of the elution chamber  216 . The illustrated lid  224  is a screw-top lid; however, any other lid which (removably) provides access to the opening  302 . 
         [0159]      FIGS. 27 and 28  illustrate the valve assembly  206  in more detail. Valve assembly  206  includes a housing  310 . The housing  310  includes a chamber  312  therein, a slot  314 , and projections  316  extending therefrom. The chamber  312  includes a pump  318  therein. A lid  320  is provided at an end of the housing to seal the chamber  310 . The lid includes first and second openings  322 ,  324 , extending therethrough and providing fluid communication with the chamber  312 . 
         [0160]    When the openings  322 ,  324  are not aligned with openings  238   a - h,  the contents of the chamber  312  are sealed within the valve assembly; however, when the openings  322 ,  324  are aligned with openings  238   a - h,  the contents of the chamber  312  are releasable from the chamber  312 . The slot  314  is used to guide the openings  322 , 324  to the location where the openings  322 ,  324  are aligned with the openings  238   a - h.  The pump  318  is used to transfer the contents from the chamber  312  and into the reaction chamber  214  through the openings  322 ,  324 . 
         [0161]    The cassette  200  is assembled by inserting the valve assemblies  206   a - h  into the holding chambers  204   a - h  of the housing. The locking element  207  may be connected to the housing to secure valve assemblies  206   a - h  in the holding chambers  204   a - h.  The waste chamber and elution chamber  216  assembly is inserted into the housing  202  and the lid  224  is secured to the housing  202 . The plunger  218  is also inserted into the reaction chamber  208  and the lid  222  is secured to the housing. 
         [0162]    In use, as shown in  FIG. 29 , the first lid  222  is removed to provide access to the opening  234  of the reaction chamber  208 . A sample of cells  350  is placed into the cassette  200  using a pipette  352 . The cells in the sample include nucleic acid. The pipette  352  having the sample therein is placed in the reaction chamber  208 . The sample is released from the pipette  352 . 
         [0163]    As shown in  FIG. 30 , the PK solution is added to the sample. The PK solution is added by rotating the valve assembly  206   c  relative to the housing  202 . At least one of the openings  322 ,  324  of the valve assembly  206   c  is aligned with the opening  242   c  in the holding chamber  204   c  to release the PK solution from the holding chamber  204   c  and into the reaction chamber  208  through the opening  238   c  in the housing  202 . 
         [0164]    The PK Solution is mixed with the sample by pumping the mixture with the plunger  218 . As described hereinabove, the PK solution destroys the wall so the cells of the sample, creating bulk material and nucleic acid in the bulk material. 
         [0165]    As shown in  FIG. 31 , the lysis solution is added to the sample. The valve assembly  206   b  operates in the same manner as valve assembly  206   c  to transfer the lysis solution in the holding chamber  204   b  into the reaction chamber  208 . The sample is typically pumped to mix the lysis solution with the mixed PK solution and sample. The lysis solution is typically a salt or detergent, and is used to solubilize the bulk material, as discussed hereinabove. 
         [0166]    As shown in  FIG. 32 , a binding solution is added to the sample, PK solution and lysis solution. Valve assembly  206   a  operates in the same manner as valve assembly  206   c  to transfer the binding solution in the holding chamber  204   a  into the reaction chamber  208 . The solution is pumped to mix the binding solution with the PK solution, lysis solution and sample. The binding solution is typically hydrophobic and increases sale in the solution. 
         [0167]    As shown in  FIG. 33 , the solution is pumped through the particles in the particle chamber  210 . The nucleic acid binds to the particles in the particle chamber, while the remaining solution flows into the waste chamber  212 , and, if needed, the waste overflow chamber  214 . As described above, when the opening  298  in the waste chamber  212  is aligned with the opening  300  in the waste overflow chamber  214 , the solution can flow into the waste overflow chamber  214  from the waste chamber  212 . 
         [0168]    As shown in  FIG. 34 , the washing solution is added to the reaction chamber  208  by operating the valve assembly  206   d  in the same manner as valve assembly  206   c  to transfer the washing solution from the holding chamber  204   d  into the reaction chamber  208 . 
         [0169]    As shown in  FIG. 35 , the first washing solution is pumped through the particle chamber  210  and into the waste chamber  212 , and, if needed, the waste overflow chamber  214 . 
         [0170]    As shown in  FIG. 36 , a second washing solution is added to the reaction chamber  208  by operating the valve assembly  206   e  in the same manner as valve assembly  206   c  to transfer the washing solution from the holding chamber  204   e  into the reaction chamber  208 . 
         [0171]    As shown in  FIG. 37 , the second washing solution is pumped through the particle chamber  210  and into the waste chamber  212 , and, if needed, the waste overflow chamber  214 . 
         [0172]    As shown in  FIG. 38 , an elution solution is added to the reaction chamber  208  by operating the valve assembly  206   f  in the same manner as valve assembly  206   c  to transfer the elution solution from the holding chamber  204   f  into the reaction chamber  208 . 
         [0173]    The waste chamber and elution chamber assembly is rotated to align the opening  296  of the elution chamber  216  with the opening  252  of the particle chamber  210  such that the elution solution is transferable into the elution chamber  216 . It will be appreciated that the opening  296  can be aligned with the opening  252  before or after the elution solution is added to the reaction chamber  208 . 
         [0174]    As shown in  FIG. 39 , the elution solution is pumped through the particle chamber  210  to elute the bound nucleic acid. The nucleic acid and elution solution flow into the elution chamber  216 . 
         [0175]    As shown in  FIG. 40 , the prepared sample of nucleic acid may be accessed using a pipette  354 . The second lid  224  is removed to provide access to the opening  302  in the elution chamber  216 . The pipette  354  is inserted into the opening  302  and the prepared sample of nucleic acid is withdrawn. 
         [0176]    It will be appreciated that the cassette  200  can be placed with similar cassettes into a magazine or rack for containing a series of cassettes. The magazine or rack can be placed into an instrument, and a protocol may be selected for preparing the sample in the cassette  200  in the instrument. 
         [0177]    Cassette  200  may include one or more heating elements as described hereinabove with respect to cassette  100 . 
         [0178]    The cassettes  100 ,  200  may be disposable. 
         [0179]    It will be appreciated that although the cassettes  100 ,  200  have been described with respect to breaking cells to extract nucleic acid, the cassettes  100 ,  200  can be used to break cells to extract other cell components, such as, for example, protein. Also, although a lysis solution has been described as being used to break up cells, it will be appreciated that any substance that can break up cells, such as, for example, reagents, enzymes, catatropic salts, other lysis solutions and the like. 
         [0180]    The cassettes described herein are advantageous because it is closed. There is no contamination of the sample during the process. In addition, a fewer number of samples, including as few as one sample, may be prepared. 
         [0181]    The foregoing description with attached drawings is only illustrative of possible embodiments of the described method and should only be construed as such. Other persons of ordinary skill in the art will realize that many other specific embodiments are possible that fall within the scope and spirit of the present idea. The scope of the invention is indicated by the following claims rather than by the foregoing description. Any and all modifications which come within the meaning and range of equivalency of the following claims are to be considered within their scope.