Abstract:
A ventilation assembly for a machine for the preparation of radiopharmaceuticals, consisting of suction means and release means for generating a circulation of air within a vacuum dispensing chamber, a product filling calibrator accommodated in the dispensing chamber and presenting a cavity accommodating a container to be filled with radiopharmaceutical, and a suction conduit adapted to connect a bottom portion of the accommodating cavity to the suction means for creating a one-way flow in the accommodating cavity.

Description:
[0001]     The present invention relates to a ventilation assembly for a machine for the preparation of radiopharmaceuticals.  
       BACKGROUND OF THE INVENTION  
       [0002]     Generally, modern automated machines for the preparation of radiopharmaceuticals comprise a calibrator, within which is accommodated the flask in which the radiopharmaceuticals are deposited and a device for releasing the products within the flask.  
         [0003]     Since it is often difficult to ensure a fluid-tight coupling between the flask and the intake device, especially when different types of vials may be used on the same machine, the need to avail of a solution so as to ensure an environment with an excellent aseptic degree is felt, in order to prevent undesired, polluting materials from being deposited within the flask itself.  
       SUMMARY OF THE INVENTION  
       [0004]     The object of the present invention is a ventilation assembly for a machine for the preparation of radiopharmaceuticals, comprising suction means and release means for generating a circulation of air within a vacuum dispensing chamber, a product filling calibrator accommodated in said dispensing chamber and presenting a accommodating cavity for a container to be filled with radiopharmaceutical, and a suction conduit adapted to connect a bottom portion of said accommodating cavity to said suction means for creating a one-way flow in said accommodating cavity.  
         [0005]     According to a preferred embodiment of the present invention, said suction means comprise a Venturi nozzle fed with compressed air.  
         [0006]     According to a further preferred embodiment of the present invention, said connection means comprise a gap made in said product filling calibrator and extending about said housing cavity. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]     The following example is provided by way of non-limiting illustration for better understanding of the invention with the help of the figures in the accompanying drawing, in which:  
         [0008]      FIG. 1  is a schematic view of part of a machine for the preparation of radiopharmaceuticals comprising the ventilation assembly of the present invention; and  
         [0009]      FIG. 2  is a section of the product filling calibrator of the ventilation assembly in  FIG. 1 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0010]     In  FIG. 1 , it is indicated as a whole by  1  a ventilation assembly object of the present invention, which operates within part of a machine  2  for the preparation of radiopharmaceuticals comprising a dispensing chamber  3 , a deposit chamber  4  of empty containers to be filled with the radiopharmaceutical and a collection chamber  5  of the containers appropriately filled with the radiopharmaceutical. Both deposit chamber  4  and collection chamber  5  are connected to dispensing chamber  3 , from which they can be fluid-tightly insulated by means of two respective doors  4   a  and  5   a.    
         [0011]     Assembly  1  comprises a ventilator  6  which operates by suction within dispensing chamber  3 , deposit chamber  4  and collection chamber  5 , a Venturi device  7  which operates in release and suction within dispensing chamber  3  and a product filling calibrator  8  connected to Venturi device  7 .  
         [0012]     In particular, ventilator  6  is connected to a conduit network  9  in which a first branch  10  communicates with dispensing chamber  3  through an internal cartridge HEPA filter  11 , a second branch  12  communicates with the deposit chamber  4  through a further internal cartridge HEPA filter  13  and a third branch  14  communicates with a collection chamber  5  through a further internal cartridge HEPA filter  15 .  
         [0013]     Assembly  1  further comprises an air intake device  16  (known and not shown in detail) into deposit chamber  4  and collection chamber  5  through two conduit branches  17  and  18  and two respective internal cartridge HEPA filters  19  and  20 .  
         [0014]     Venturi device  7  comprises a first conduit  21  communicating with dispensing chamber  3  through an internal cartridge HEPA filter  22 , a second conduit  23  presenting a section whose diameter is larger than that of the first conduit  21 , a Venturi nozzle  24  arranged between the first conduit  21  and the second conduit  23 , and a compressed air intake device  25  (known and not described in detail) directly connected to Venturi nozzle  24 . The second conduit  23  communicates with dispensing chamber  3  through a further internal cartridge HEPA filter  26 .  
         [0015]     As shown in  FIG. 2 , product filling calibrator  8  comprises a cylindrical double layer Plexiglas liner  27 , which defines a cylindrical cavity  28  delimited by an inner layer  29 , and in which container C (flask or syringe) is accommodated, and a gap  30  delimited by the inner layer  29  and by an outer layer  31  and connected to cylindrical cavity  28  at a bottom wall of the inner layer  29 .  
         [0016]     Calibrator  8  comprises a hollow ring  32  arranged about an upper end  27   a  of the double layer cylindrical liner  27 . Hollow ring  32  communicates with gap  30  and is connected by means of a conduit  33  to first conduit  21 .  
         [0017]     In use, once ventilator  6  has generated the required vacuum in dispensing chamber  3 , device  25  inputs compressed air at the Venturi nozzle, which generates a flow crossing the two HEPA filters  22  and  26 . In particular, the flow of air enters dispensing chamber  3  through HEPA filter  26 , arranged near calibrator  8 , and is output from dispensing chamber  3  through HEPA filter  22 .  
         [0018]     Thanks to the connection between gap  30  and Venturi device  7 , part of the flow is taken in through calibrator  8  so that container C during filling is constantly immersed in a downward current which ensures an ISO  5  classified environment (REF. ISO 14644-1).  
         [0019]     Ventilator  6  creates a vacuum in deposit chamber  4  and in collection chamber  5  higher than that created in dispensing chamber  3 . Such difference of pressure between deposit chamber  4  and collection chamber  5  and dispensing chamber  3 , and the presence of fluid-tight doors  4   a  and  5   a , makes it possible to access to chambers  4  and  5  respectively for depositing the empty containers or taking the filled containers without disturbing the environment in dispensing chamber  3  and, therefore, without interrupting the preparation of the radiopharmaceutical, which will continuously proceed.  
         [0020]     Indeed, concerning deposit chamber  4 , the operator opens an external door (not shown), deposits the containers (flasks and syringes) and closes the outer door again. At this point, the operator waits for the required vacuum to be recreated, and controls opening of door  4   a  and subsequent collection of the deposited containers by a robot.  
         [0021]     Concerning collection chamber  5 , the operator opens an outer door (not shown), loads a shielded casing and closes the outer flap. At this point, the operator waits for the required vacuum to be recreated, and controls opening of door  5   a  and subsequent collection of the shielded casing by a robot. The radiopharmaceutical container is automatically inserted in the shielded casing, which is returned to collection chamber  5 . Door  5   a  is closed again and the operator may open the other door again and collect the shield casing containing the radiopharmaceutical container.  
         [0022]     As apparent from the description above, the ventilation assembly according to the present invention ensures that the machine for the preparation of radiopharmaceuticals may perform the filling operation in an aseptic environment. In this way, the containers can be filled without necessarily ensuring fluid-tight coupling between the container and the filling device. Such advantage increases the versatility of the machine which may use differently sized containers without requiring demanding changes.  
         [0023]     Another important advantages that the ventilation assembly offers is that the filling operation may be continuously performed without depositing and collecting operations disturbing the environment in the dispensing chamber.