Abstract:
A method provides for procuring platelet rich plasma (PRP) from a sample of whole blood in a vial. The method includes the steps of: separating the whole blood into layers through centrifugation with an upper layer containing platelet poor plasma (PPP) and a PRP layer below the upper layer containing PRP; adjusting an end point of a first range of motion of an extractor relative to a position of the PRP layer; moving the extractor through the first range of motion through the vial, PPP passing out from the upper layer through the extractor; and after the extractor reaches the end point of the first range of motion, extracting the PRP through the extractor and collecting the PRP.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to methods and devices for collecting separate components of whole blood. 
     Platelets have been known to play critical roles in hemostasis and wound healing through a multitude of complex biological functions and interactions. In clinical applications, platelets are used in elevated concentrations known as platelet rich plasma (PRP). 
     SUMMARY 
     A method according to the present invention provides for procuring platelet rich plasma (PRP) from a sample of whole blood in a vial. The method comprises the steps of: separating the whole blood into layers through centrifugation with an upper layer containing platelet poor plasma (PPP) and a PRP layer below the upper layer containing PRP; adjusting an end point of a first range of motion of an extractor relative to a position of the PRP layer; moving the extractor through the first range of motion through the vial, PPP passing out from the upper layer through the extractor; and after the extractor reaches the end point of the first range of motion, extracting the PRP through the extractor and collecting the PRP. 
     Preferably, the step of adjusting the end point of the first range of motion comprises setting the position of a stop against which an abutment associated with the extractor engages at the end point. 
     Preferably, the extractor comprises a piston sized to tightly fit through the vial and wherein the PPP passes out of the upper layer through an orifice in the piston. In one aspect of the invention the step of extracting the PRP comprises moving the piston beyond the end point of the first range of motion through a second range of motion and passing the PRP through the orifice while moving the extractor through the second range of motion. Preferably, the PPP is passed through a first flow path as the extractor moves through the first range of motion and a diverter is engaged as the extractor reaches the end point, the diverter sending the PRP through a separate second flow path. For instance, an abutment associated with the extractor can engage a lever on the diverter as the extractor reaches the end point to send flow from the extractor through the second flow path. Preferably, the diverter comprises a three-way valve. 
     In one aspect of the invention, the orifice is disposed at a distal tip of a needle in the extractor. 
     In one aspect of the invention a handle is associated with the extractor and a user in one continuous motion, by pressing on the handle, moves the extractor through the first range of motion and the second range of motion. 
     In one aspect of the invention, the step of extracting the PRP comprises passing a tip of a needle through the orifice to the PRP layer and extracting the PRP through the needle. 
     Preferably, the sample of whole blood is collected from a patient and further comprising the step of applying the PRP to a site on the patient&#39;s body to promote healing. 
     A device according to the present invention provides for collecting platelet rich plasma (PRP) from a sample in a vial of centrifugally fractionated whole blood having an upper layer comprising platelet poor plasma and a PRP layer containing the PRP. The device comprises an extractor movable through the vial in a first adjustable range of motion, the first range of motion having an end point associated with a position of the PRP. An adjustment between the extractor and the vial adjusts the end point of the range of motion to correspond to the position of the PRP. A first extraction flow path through the extractor is associated with the first range of motion, the extractor being adapted to flow the PPP through the first extraction flow path as the extractor moves through the first range of motion and a second extraction flow path is associated with the first range of motion end point, the second extraction flow path leading to a PRP collection receptacle. 
     Preferably, the device further comprises a stop associated with the vial and an abutment associated with the extractor, the abutment engaging the stop at the end point. 
     Preferably, the extractor comprises a piston sized to tightly fit through the vial wherein the PPP passes out of the upper layer through an orifice in the piston. 
     In one aspect of the invention the extractor further comprises a second range of motion beyond the end point of the first range of motion, the second extraction flow path being associated with the second range of motion. Preferably, a diverter is disposed between the extractor and the first extraction flow path and between the extractor and the second extraction flow path, the diverter being operable between a first diverter position in which to divert flow from the extractor through first extraction flow path while the extractor moves through the first range of motion and a second diverter position in which to divert flow through the second extraction flow path after the extractor reaches the end point of the first range of motion. For instance an abutment associated with the extractor can be provided and which is engageable with a lever on the diverter as the extractor reaches the end point of the first range of motion, the lever having a lever first position prior to engagement by the abutment wherein the diverter is in the diverter first position and a lever second position after engagement by the abutment wherein the diverter is in the diverter second position. Preferably, the diverter comprises a three-way valve. 
     In one aspect of the invention, the orifice is disposed at a distal tip of a needle in the extractor. 
     In one aspect of the invention, a handle is associated with the extractor, the handle being oriented to allow a user in one continuous motion, by pressing on the handle, to move the extractor through the first range of motion and the second range of motion. 
     In one aspect of the invention, an extraction needle extends through the orifice and the second extraction flow path extends through the extraction needle. 
     In one aspect of the invention, the device further comprises a housing having a holder for holding the vial and the extractor is connected to the housing. The adjustment can be adapted to move the holder relative to the housing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a flow chart illustrating the process of extracting PPP and PRP; 
         FIG. 2A  is an exploded view of a blood container used in the extraction process in  FIG. 1 ; 
         FIG. 2B  is an enlarged view of the blood container in  FIG. 2A ; 
         FIG. 2C  is an enlarged view of the internal channel of the piston assembly in  FIG. 2A ; 
         FIG. 3  is a front perspective view of an embodiment an extraction device according to the present invention; 
         FIG. 4A  is a plan view of aligning the buffy coat layer to the pointers in the extraction device; 
         FIG. 4B  is a plan view of inserting the PPP syringe into the extraction device; 
         FIG. 4C  is a plan view of extracting an excess amount of PPP to the PPP syringe using the extraction device; 
         FIG. 4D  is a plan view of inserting the PRP syringe into the extraction device after extracting the excess amount of PPP; 
         FIG. 4E  is a plan view of extracting a predetermined amount of PRP to the PRP syringe using the extraction device; 
         FIG. 4F  is a front perspective view of a PPP stopper used in an alternative embodiment of the PPP syringe in  FIG. 4B ; 
         FIG. 4G  is a front perspective view of a PRP stopper used in an alternative embodiment of the PRP syringe in  FIG. 4D ; 
         FIG. 4H  is a front perspective view of the PPP stopper and the PRP stopper loaded onto the PPP syringe and the PRP syringe with the spacers respectively; 
         FIG. 4I  is a front perspective view of the exaction device extracting an excess amount of PPP with the PPP syringe loaded with the PPP stopper and spacer; 
         FIG. 4J  is a front perspective view of the exaction device extracting a predetermined amount of PRP with the PRP syringe loaded with the PRP stopper and spacer; 
         FIG. 5  is an exploded view of an alternative embodiment of the extraction device; 
         FIG. 6  is a front perspective view of aligning the buffy coat layer with the indicator rib of the extraction device in  FIG. 5 ; 
         FIG. 7  is a front perspective view of the extraction device extracting an excess amount of PPP; 
         FIG. 8  is a front perspective view of the extraction device extracting a predetermined amount of PRP; 
         FIG. 9  is a back perspective view of an alternative embodiment of the extraction assembly; 
         FIG. 10  is a front perspective view of the extraction assembly in  FIG. 9 ; 
         FIG. 11  is a back perspective view of the extraction device with the extraction assembly in  FIG. 9 ; 
         FIG. 12  is a front perspective view of the switch from extracting PPP to PRP in the extraction assembly; 
         FIG. 13  is a front perspective view of the extraction assembly after the predetermined amount of PRP has been extracted; 
         FIG. 14  is a front perspective view of an alternative embodiment of the PPP cover and PRP cover; 
         FIG. 15  is a front perspective view of the PPP cover and PRP cover in operation. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  shows a process of separating whole blood into different components according to the present invention. At step  10 , a whole blood sample is first extracted from a patient to a blood container. As the whole blood sample is extracted, it is mixed together with anticoagulant (typically 10-15% by volume) in the blood container. At step  12 , the blood container is put into a centrifuge to undergo centrifugation, preferably at 3000 g level for 15 minutes. Any bench top centrifuge capable of handling 15 cc tubes can be used. After centrifugation, the whole blood sample will have three layers, a red blood cells layer at the bottom of the blood container; a buffy coat layer containing most of the platelets, resting on top of the red blood cells layer; a top layer with mostly plasma, resting on top of the buffy coat layer. The top layer is commonly referred to as platelet poor plasma (PPP) as the amount of platelets in it is almost non-existent. For purpose of the present invention, platelet rich plasma (PRP) is a mixture of some PPP, some red blood cells, and the entire amount of the buffy coat layer, as it is difficult to extract just the concentrated platelets in the buffy coat layer without also extracting any PPP or red blood cells. The PRP has a platelet concentration much higher than a base whole blood sample of the same volume (typically 4-5 folds over base blood). At step  14 , the post centrifugation whole blood sample is directly placed into an extraction device and is separated into different components, specifically platelet poor plasma and platelet rich plasma. 
       FIGS. 2A-C  depicts a blood container  20  used in steps  10 - 14  in  FIG. 1  according to the present invention. In  FIG. 2A , the blood container  20  has a syringe cap  30 , a syringe barrel  22  with flange  24 , a first seal  44 , a piston assembly  26 , a second seal  35 , a needle guide  37 , a third seal  41 , a piston cap  28 , and a removable plunger  32  that threads into the piston cap  28  fitted within. The syringe cap  30  is fitted over a distal tip  31  of the syringe barrel once the whole blood sample has been extracted from the patient and mixed with the anticoagulant and serves to prevent whole blood sample from leaking out of the blood container. In one embodiment a Becton, Dickinson and Company (BD) 10 cc syringe is used as the blood container  20  and other suitable syringes can be used without limitation. The syringe barrel  22  has a circular hollow chamber  21  with a raised rim  23  therewithin. 
     The piston assembly  26  is slidably fitted into the chamber  21  of the syringe barrel  22 . The piston assembly has a main body  34  with a distal end  36  and a proximal end  38 . The main body  34  has an outer slot  40  near the distal end, aperture  33   a  and  33   b  (not shown) located on opposite side of the main body near respectively near the proximal end, and an inner channel  42  (as seen in  FIG. 2B ). The first seal  44  is fitted onto the outer slot to keep the whole blood sample from spilling out of the syringe barrel. The inner channel  42  of the main body  34  has also a distal end  48  and a proximal end  46 . The inner channel  42  has a generally an hour-glass shape with a seal  50  located at a neck portion  52  of the inner channel  42 . The structure of the inner channel is discussed in more details in  FIG. 2C . 
     The proximal end  38  of the main body  34  has an inner hollow area  55  (shown in  FIG. 2C ) that has the same diameter as the needle guide  37  and a lower portion  51  of the piston cap  28 . The second seal  35  has an inner area (not shown) that is shaped to allow mounting onto a lower portion  39  of the needle guide  37 , thus attaching the second seal onto the needle guide. The second seal serves to prevent the whole blood sample from spilling out of the syringe barrel. The needle guide  37  along with the second seal  35  are slidably received in the hollow area  55 . The needle guide  37  has a central hollow channel (not shown) that is aligned with the inner channel  42  to allow an extraction needle to go through the needle guide and the piston assembly during the PPP and PRP extraction process discussed in more details below. 
     The piston cap  28  has a lower portion  51   a , an upper portion  51   b , and a pair of tabs  45   a  and  45   b  (not shown). Tab  45   a  and  45   b  are integrally formed with the piston cap  28  and are each defined by substantially u-shaped channels  57   a  and  57   b  (not shown) respectively. Tabs  45   a  and  45   b  are located on opposite sides of the piston cap. 
     The lower portion  51   a  has a slot  43 . The third seal  41  mounts onto the slot  43  to prevent the whole blood sample from spilling out of the syringe barrel. The lower portion  51   a  along with the third seal  41  are slidably received in the hollow area  55  and attaches to the main body  34  by locking tabs  45   a  and  45   b  (now shown) into the apertures  33   a  and  33   b  (not shown) respectively. The plunger  32  attaches to the upper portion  51   b  of the piston cap  28 . The upper portion  51   b  has a hollow inner area that is shaped to receive a lower portion  53  of the removable plunger  32 . A lip portion  49  of the upper portion  51   b  clips onto a spherical portion  47  of the lower portion  53  to secure the removable plunger  32  to the piston cap  28 . The syringe cap  30 , the piston assembly  26 , and the piston cap  28  together will help keep the whole blood sample sterile. The BD 10 cc syringe is available from Becton, Dickinson and Company of Franklin Lakes, N.J. 
     In one embodiment, before extracting the whole blood sample from the patient, a desired amount of anticoagulant is first extracted into the chamber  21  by conventional means. In order to prevent accidentally injection of the anticoagulant into the patient when extracting the whole blood sample, a skirt  32   a  located on the removable plunger  32  is used to limit the travel of the removable plunger  32  towards the distal end  31 . The skirt  32   a  has a bigger diameter than the diameter of the chamber  22  such that when the removable plunger  32  is pushed towards the distal end  31 , the removable plunger can only travel so far in the chamber  22  until the skirt  32   a  comes in contact with the flange  24 . The location of the skirt  32   a  on the removable plunger  32  is chosen so that there will be enough room in the chamber  22  for the desire amount of anticoagulant when the skirt  32   a  comes in contact with the flange  24 . 
     When extracting the whole blood sample from the patient, the removable plunger  32  is pulled away from the distal end  31 , along with the piston assembly  26 , and the piston cap  28  since they are all connected together. The dimensions of the piston assembly  26 , the piston cap  28 , and the removable plunger  32  are chosen so that when a skirt  61  on the main body  34  of the piston assembly  26  comes in contact with the raised rim  23 , a predetermined volume of the whole blood sample has been extracted into the chamber  21 . The blood container  20  will be disconnected from the patient and the syringe cap  30  is fitted over the distal tip  31  to prevent leakage of the whole blood sample. 
     When the skirt  61  comes in contact with the raised rim  23 , the removable plunger  32  is stopped and the upper portion  51   b  of the piston cap  28  is exposed outside of the chamber  21  due to the dimensions of the piston assembly  26 , the piston cap  28 , and the removable plunger  32 . This signals to a user who is extracting the whole blood sample that a predetermined volume has been extracted. Then the user can remove the removable plunger  32  from the blood container  20  by pulling the plunger away from the distal end  31 . When the removable plunger  32  is pulled away from the distal end  31 , the spherical portion  47  causes the upper portion  51   b  to expand outward, allowing the plunger to be separated from the piston cap. However, during the whole blood sample extraction, the upper portion is prevented from expanding outward by the chamber  21 . Thus, removal of the removable plunger  32  is only possible after the upper portion  51  is outside of the chamber  21 . 
     After removing the removable plunger  32 , the blood container  20  containing the whole blood sample is centrifuged as in step  12  of  FIG. 1 . The piston cap  28  stays connected with the piston assembly  26  during centrifugation process to prevent contamination of the whole blood sample. After centrifugation, the piston cap  28  is removed from the piston assembly  26  by first pressing down on the tabs  45   a  and  45   b  inward towards each other to release the tabs from apertures  33   a  and  33   b , then pulling the piston cap  28  away from the piston assembly  26 . Then the blood container  20  can be placed into an extraction device to extract the PPP and PRP in accordance with the present invention. 
       FIG. 2C  shows the structure of the inner channel of the piston assembly main body in  FIG. 2A . The proximate end  48  and an enlarged distal end  46  of the inner channel  42  are enlarged, with the narrower neck portion  52  in between. The diameter of the distal end  46  gradually narrows up to the diameter of the neck portion  52 . The gradual reduction in the diameter helps to guide the needle to pierce the seal  50 . It also conforms to the way fluid flows during extraction, thus minimizing potential fluid entrapment in the inner channel. 
       FIG. 3  depicts an embodiment of an extraction device  60  used to extract the PPP and the PRP according to the present invention. The extraction device  60  has a base  62  supporting a main body  64 . The base  62  and the main body  64  can be molded as one piece or separate pieces. The main body  64  has an inner channel  66 . The inner channel  66  preferably has a width suitable to contain the blood container  20 , but less than the flange  24  of the blood container so that when the blood container is inserted into the inner channel  66 , the inner channel  66  will hold the blood container  20  above the base  62 . A sleeve  68  has an inner portion  70  and an outer portion  72 . The inner portion  70  slides onto the main body  64  and receives the flange  29 . The sleeve  68  has a locking mechanism  74  that fixes the position of the sleeve relative to the main body  64 . The locking mechanism  74  can be a turning knob that threads into both the sleeve and the main body  64 , so that as the knob is turned towards the main body, the knob compresses on the sleeve  68  and the compression holds the sleeve  68  in a fixed position. Any other suitable locking mechanism can be used. A pair of pointers  76   a ,  76   b  are formed integrally with the sleeve  64  at a location on the sleeve  64  that is predetermined based on the amount of PRP to be extracted. 
       FIGS. 4A-F  depict an embodiment of the method of extracting PPP and PRP according to the present invention. In  FIG. 4A , the blood container  20  containing the post centrifuged whole blood sample  98  having a red blood cells layer  101 , a buffy coat layer  99 , and a PPP layer  100 , and the piston assembly  26  is first placed into the inner channel  66  of the main body  64  of the extraction device  60 . The position of the sleeve  68  relative to the main body  64  is adjusted by aligning the point teeth  76   a ,  76   b  to the position of the buffy coat layer  99  in the blood container  20 . The alignment of the buffy coat layer to the pointers  76   a ,  76   b  eliminates the variations in hematocrit between patients and ensures a predetermined amount of PRP will be extracted, because the distance between the top of the sleeve  68  and the location of the pointers  76   a ,  76   b , the length of the needle  93 , and the length of the needle  111 , the length of the syringe barrel  105 , the length of the syringe barrel  97  are chosen based on the predetermined PRP extraction volume. The locking mechanism  74  is then engaged to lock the sleeve  68  in place. 
     In  FIG. 4B , an empty PPP syringe  91  with barrel  97 , plunger  103  and a needle  93  attached at the tip  31  is inserted into the piston assembly  26  with the needle  93  piercing through the seal  50 . In  FIG. 4C , the PPP syringe  91  is placed into the inner channel  66  of the extraction device  60 . The PPP syringe barrel  97  is depressed, pushing down the piston assembly  26  to descend. As the PPP syringe  91  descends, the needle  93  will enter into the blood container  20 , pierce through the seal  50  and will come in contact with the PPP  100  in the blood container  20 . The excess PPP  100   b  will flow into the PPP syringe barrel  97  until the flange  95  comes in contact with the top of the sleeve  68 , leaving behind a predetermined amount of PPP  100   a . The predetermined volume is small, which is designed to maximize the PRP extraction without unduly disturbing the buffy coat layer in the process of extracting the excess PPP. In one embodiment, a predetermined amount of PPP remaining is about 0.8 cc. The PPP syringe  91  is then removed after collecting the excess PPP  100   b . A doctor can then administer the PPP  100   b  to a patient as an adjunct to healing and hemostasis. 
     In  FIGS. 4D-4E , a PRP syringe  105  with barrel  113 , plunger  109  and needle  111  is inserted into the inner channel  66  through seal  50  to extract a predetermined amount of PRP. The barrel  113  is pressed down until the flange  107  comes in contact with the top of the sleeve  68 . As the barrel  113  descends, so does the piston assembly  26 . The needle  111  will come in contact with and extract the remaining amount of PPP  101   a , and then the buffy coat layer  99 , and finally a predetermined amount of red blood cells  101   b  into barrel  113 . In one embodiment, the predetermined volume of red blood cells  101   b  is about 0.8 cc and the volume of the buffy coat layer  99  is about 01. To 0.2 cc. The mixture of the extracted PPP  101   b , the buffy coat layer  99 , and red blood cells  101   b  becomes the PRP  115 . A doctor can then administer the PRP  115  to a patient for healing and hemostasis purpose. 
       FIGS. 4F-4J  depict an alternative embodiment of the PPP syringe  91  and the PRP syringe  105 . 
     In  FIG. 4F , a PPP stopper  88  is added to the PPP syringe  91  (as shown in  FIG. 4H ). The PPP stopper has a body  90  that has generally the same diameter as the inner portion  70  of the sleeve  68  and an enlarged head  92  formed integrally at the upper end of the body. The enlarged head  92  has a depth of h1. A cylindrical channel  94  is formed at the central portion of the PRP stopper  88  and goes through the enlarged head  92  and the body  90 . Both the upper and the lower end of the cylindrical channel  94  are open. A depression  96  is formed above the top of the cylindrical channel  84  to hold the flange  95  of the PPP syringe  91  during the PPP extraction process. 
       FIG. 4G  depicts a PRP stopper  78  which is added to the PRP syringe  105  (as shown in  FIG. 4H ). The PRP stopper  78  has a body  80  that has generally the same diameter as the inner portion  70  of the sleeve  68  and an enlarged head  82  formed integrally at the upper end of the body. The enlarged head  82  has a depth of h2. A cylindrical channel  84  is formed at the central portion of the PRP stopper and goes through the enlarged head  82  and the body  80 . Both the upper and the lower end of the cylindrical channel are open. A depression  86  is formed above the top of the cylindrical channel  84  to hold the flange  107  of the PRP syringe  105  during PRP extraction process. 
     In  FIG. 4H , after inserting the PPP syringe  91  and the PRP syringe  105  into the PPP stopper  78  and the PRP stopper  88  respectively, the PPP needle  93  and the PRP needle  111  are inserted through a PPP spacer  117   a  and a PRP spacer  117   b  respectively. The difference between the enlarged head  92  of the PPP stopper  88  and the enlarged head  82  of the PRP stopper  78  correspond to a predetermined volume of PRP to be extracted. 
     In  FIG. 4I , the PPP syringe  91  loaded with the PPP stopper  88 , the spacer  117   a , the barrel  97 , the plunger  103  and the needle  93  (not shown) is inserted into the inner channel  66 . The barrel  97  is pressed down along with the PPP stopper  88 , causing the needle  93  to pierce through the seal  50  (not shown) and come in contact with the PPP  100  (not shown) in the blood container  20 . An excess amount of PPP  100   b  will flow into the PPP syringe barrel  97  until the bottom of the enlarged head  92  comes in contact with the top of the sleeve  68 , leaving behind a predetermined amount of PPP  100   a . The PPP syringe  91  is then removed after collecting the excess amount of PPP  100   b . A doctor can then administer the PPP  100   b  to a patient an adjunct to healing and hemostasis. 
     In  FIG. 4J , the PRP syringe  105  loaded with the PRP stopper  78 , the spacer  117   b , the barrel  113 , the plunger  109  and the needle  111  (not shown) is inserted into the inner channel  66  through seal  50  to extract a predetermined amount of PRP. The barrel  113  is pressed down along with the PRP stopper  78  until the bottom of the enlarged head  82  comes in contact with the top of the sleeve  68 . As the barrel  113  descends, the piston assembly  26  descends as well. The needle  111  will come in contact with and extract the remaining amount of PPP  100   a  (not shown), and then the buffy coat layer  99  (not shown), and finally a predetermined amount of red blood cells  101   b  (not shown) into barrel  113 . The mixture of the extracted PPP  101   b , the buffy coat layer  99 , and red blood cells  101   b  becomes the PRP  115 . A doctor can then administer the PRP  115  to a patient for healing and hemostasis purpose. 
     Turning now to  FIG. 5  which illustrates an alternative embodiment of the invention. An extraction device  200  has a front housing member  202 , a back housing member  204 , which is connected to the front housing member  202  in the assembled extraction device  200 . An internal rib structure  206  in the back housing member  204  and the internal rib structure in the front housing member (not shown) hold the internal components of the assembled extraction device  200  in place and provide rigidity. A holder  208  is threadably connected to an adjustment knob  210  disposed within the extraction device  200 . A blood container  212  is placed into the blood container holder via open space created by side channels  214   a ,  214   b  of the front housing member  202  and the back housing member  204  respectively. The adjustment knob  210  is exposed via open space created by lower side channels  218   a ,  218   b  of the front housing member  202  and lower side channels  218   c ,  218   d  of the back housing member  204  respectively. This allows the holder  208  to be raised or lowered by turning the adjustment knob  210 , which in turn raises or lowers the blood container  212 . An extraction assembly  220  is disposed within the extraction device  200  above the blood container  212 . The extraction assembly  220  has a housing member  222  and a handle  224  with handle bars  226   a ,  226   b . The handle bars  226   a ,  226   b  are exposed via open space formed by side channels  216   a ,  216   c  of the front housing member  202  and side channels  216   b ,  216   d  of the back housing member  204 . Disposed within the housing member  222  is a stopcock valve  228  and an extraction needle  230  attached to a valve inlet  232  of the stopcock valve  228 . A handle  235  connects to the stopcock valve  228  to control the fluid flow and is exposed outside of the housing member  222 . A PPP extraction container  234   a  (not shown) disposed within an optional PPP cover  242   a  is connected to a valve outlet  236   a  of the stopcock valve  228  via an aperture  238   a  of the front housing member  202  and via a tube  240   a . A PRP extraction container  234   b  (not shown) disposed within an optional PRP cover  242   b  is also connected to a valve outlet  236   b  of the stopcock valve  228  in the same way via an aperture  238   b  and a tube  240   b . The PPP and PRP extraction containers can be syringe barrels with plungers attached. In one embodiment, the PPP and PRP extraction containers are the BD 5 cc syringes. 
       FIG. 6  describes the operation of the extraction device  200  in  FIG. 5  to extract PPP and a predetermined amount of PRP. After a whole blood sample is collected into the blood container  212  and is centrifuged, the blood container  212  with the post centrifuged whole blood sample in placed into the holder via the side channels  214   a  (not shown in  FIG. 6 ) and  214   b . Inside the blood container  212 , the whole blood sample has three layers, a PPP layer  244   a  on top, a buffy coat layer  244   b  under the PPP player  244   a , and a red blood cells layer  244   c  at the bottom. The adjustment knob  210  is turned to either raise or lower the blood container so that the buffy coat layer  244   b  is aligned with an indicator rib  248 . 
     Turning to  FIG. 7 , after the buffy coat layer  244   b  has been aligned with the indicator rib  248 , the handle bars  226   a  and  226   b  are pressed down to start the extraction process. As the handle bars descend, they push the extraction assembly  220  downward. The needle  230  (not shown) will come in contact with the piston  34  and pierce through the seal  50  (not shown), then the needle  230  will come in contact with the PPP layer  244   b . The stopcock handle  235  is at an initial position, which allows an excess amount of PPP to be extracted through the needle  230 , the valve inlet  232 , the valve outlet  236   a , tube  240   a  of the stopcock valve  228 , and into the PPP extraction container  234   a  (not shown). After the extraction assembly  220  has descended for a certain distance, the handle  235  of the stopcock valve  228  comes in contact with an activation rib  250  and the handle  235  is gradually turned upward. As the handle  235  is turning upward, the fluid flow inside the stopcock valve  228  changes so that some amount of PPP will continue to flow into the PPP extraction container  234   a  and some amount of PPP will start flowing into the PRP extraction container  234   b  (not shown). Once the handle  235  is turned ninety degree upward into a final position, the fluid flow change inside the stopcock valve  228  is complete and there will be only fluid flowing into the PRP extraction container  234   b . After the handle  235  is turned to the final position and as the handle bars  226   a  and  226   b  continue to descend until they come in contact with the bottom edges of the side channels  216   a - 216   d . A predetermined amount of the PPP, the buffy coat layer  244   b  and a predetermined amount of red blood cells are collected into the PRP extraction container  234   b . Only a remaining amount red blood cells  245  are left in the blood container (as shown in  FIG. 8 ). Thus, an excess amount of PPP and a predetermined amount of PRP are extracted continuously and in a sequence by pushing the handle bars  226   a  and  226   b  all the way down in a single motion. A doctor can then administer the PPP an adjunct to healing and hemostasis and the PRP to a patient for healing and hemostasis purpose. 
       FIG. 9  depicts an alternative embodiment of an extraction assembly in the extraction device  200  in  FIG. 5 . The extraction assembly  250  has a housing  252  with handle  254  disposed within. The handle  254  has turning knobs  256   a  and  256   b  at each end respectively, which are located outside of the housing  252  and the extraction device  200 . A first turning gear  258  is integrally molded into the handle  254 . Also disposed within the housing  252  is the stopcock valve  228  with the needle  230  attached to the inlet port  232  of the stopcock valve  228 . The handle  235  of the stopcock valve  228  is fitted into a second turning gear  260 , which is connected to the first turning gear  258  via gear teeth  262  and  264 . A stopper  266  is also integrally molded into the handle  254  with a front side  268   a  and an up side  268   b  (as shown in  FIG. 10 ). 
       FIGS. 11-13  depict the PPP and PRP extraction process with the extraction assembly  250  in  FIG. 9 . In  FIG. 11 , after the buffy coat layer  244   b  has been aligned with the indicator rib  248 , the handle  254  is pressed down by pressing down on the turning knobs  256   a  and  2256   b  to start the extraction process by a user. As the handle  254  is coming down, it is pushing the extraction assembly  250  down as well. The needle  230  will come in contact with the piston assembly  26  and pierce through the seal  50  of the piston assembly  26 , and then the needle  230  will come in contact with the PPP  244   a . The stopcock valve  228  is at an initial position, which allows the PPP  244   a  to be extracted through the needle  230 , the valve inlet  232 , the valve outlet  236   a  (as shown in  FIG. 7 ), the tube  240   a  (as shown in  FIG. 7 ), into the PPP extraction container  234   a  (not shown). The PPP will be extracted until the up side of the stopper comes in contact with a blocking rib  270  (as shown in  FIG. 12 ), located in the front housing member  202 . The blocking rib prevents the extraction assembly  250  from moving further down and acts a signal to a user that an appropriate amount of PPP has been extracted. 
     In  FIG. 12 , the knobs  256   a ,  256   b  on the handle  254  are turned ninety degrees backward as indicated by the direction of the arrow by the user. The turning of the handle bar will cause the front  268   a  and up side  268   b  to rotate ninety degrees backward as well. The up side  268   b  will be in front of the blocking rib  270 , while the front side  268   a  will be below the blocking rib  270 , thus the blocking rib  270  will no longer prevent the extraction assembly  250  from moving down. Also, as the handle bars  256   a ,  256   b  are rotated, the first turning gear  258  caused the second turning gear  260 , changing the fluid flow in the stopcock from PPP to PRP. 
     In  FIG. 13 , the user again pressed the knobs  256   a ,  256   b  down to collect PRP, the predetermined amount of PRP will be collected until the bottom of the housing comes in contact with a second blocking rib  272  (as shown in  FIG. 11 ), leaving behind only a remaining amount of red blood cells  245 . 
       FIG. 14  shows an alternative embodiment with the optional PPP cover  242   a  and PRP cover  242   b . Protective sleeves  280   a  and  280   b  in a compressed form slip over the PPP cover  242   a  and the PRP cover  242   b  respectively, which in turn cover the PPP extraction container  234   a  and the PRP extraction container  234   b  respectively. In one embodiment, the PPP extraction container  234   a  and the PRP extraction container  234   b  are BD 10 cc syringes. The protective sleeves  280   a  and  280   b  threadably attach to the front housing member  202 . At the bottom of the protective sleeves  280   a  and  280   b , a grasping member  282   a  and  282   b  will clip onto the plunger  286   a ,  286   b  of the PPP extraction container  234   a  and the PRP extraction container  234   b  respectively. Release button  248   a  and  248   b  are connected to the grasping members  282   a  and  282   b  respectively to release the PPP extraction containers  234   a  and the PRP extraction container  234   b  respectively. 
     Turning to  FIG. 15 , as either the PRP extraction container  234   a  or the PRP extraction container  234   b  is filled, the plunger  286   a  or  286   b  will be pushed downward, stretching the protective sleeve  280   a  or  280   b  to keep the extraction container  234   a  or  234   b  sterile. After the extraction is done, the PPP container  234   a  or the PRP container  234   b  is disconnected to the tube  240   a  or  240   b , and then the release button  248   a  or  248   b  is pressed to disconnect the appropriate grasping member from the appropriate container. The appropriate container will then drop into any desired containers for transportation without being handled manually. The protective sleeves  280   a  and  280   b  can be of plastic or any other suitable material well known in the art. 
     Various modifications and alterations of this invention will be apparent to those skilled in the art without departing from the scope and spirit of this invention. It should be understood that the invention is not limited to the embodiments disclosed herein, and that the claims should be interpreted as broadly as the prior art allows.