BAG FOR PRESERVING AND TRANSPORTING STERILE PRODUCTS IN POWDER FORM AND FOR FORMING SOLUTIONS OF SAID PRODUCTS IN THE BAG

Abstract: A bag containing a sterile product in powder form and having a port closed by a membrane through which a liquid can be fed into the bag to form a sterile solution of the powder, the bag being preferably housed in an intermediate bag which itself can be housed in an outer bag formed from three separate layers of flexible material.

Description: BAG FOR PRESERVING AND TRANSPORTING STERILE PRODUCTS IN POWDER FORM AND FOR FORMING SOLUTIONS OF SAID PRODUCTS IN THE BAG The invention relates to a bag able to preserve a product in powder form under sterile conditions and to enable a liquid to be fed into the bag to form therein a sterile solution (this term also including a dispersion or suspension) of said product. Many products obtained in sterile form in the solid state are known to be used in the liquid state as sterile solutions, suspensions, dispersions or the like. A typical example is a pharmaceutical product such as an antibiotic or vitamin, or a culture medium for micro-organisms such as cells, bacteria or moulds which at the moment of use is dissolved or dispersed in liquid. The problem of dissolving or dispersing a sterile powder in liquid while maintaining sterility is considerable and costly, and is solved in various ways, all involving problems which are summarized below by referring to two particularly important cases. For example, cell culture medium is produced in the form of powder which can be sold as such in polyethylene bags or bottles closed with a screw stopper. To be used, this product is dissolved in liquid to form a solution (typically an amino acid, electrolyte or vitamin solution) in a totally aseptic environment, this involving time and considerable cost. The sterile solution obtained in this manner is fed into a glass jar or bottle in a suitable sterile bottling environment, and the sealed bottle is despatched to the client in a special housing and protection container. The user has then to open the bottle under aseptic conditions to be able to then withdraw the solution contained in it. This method is well known, and is explained for example in lines 9-59 of column 1 of the patent US-A-4,910, 147. To solve these problems, US-A-4,910, 147 proposes to sell to the user not the product, but instead an already prepared sterile solution of the cell culture medium enclosed in a sealed flexible bag, into which the solution is fed using semi-automatic aseptic filling machines. Such bags, which are completely filled with the solution, are much more manageable than glass bottles and can be easily and economically despatched by the producer to the user who, without the need for special apparatus or a sterile environment, can directly withdraw all or part of the sterile solution through one or more ports with which the bag is provided. However, this system also presents problems because although it is relatively simple to store and transport small bags filled with liquid, in the case of bags containing a relatively large liquid volume, for example five litres or more, the hydraulic force exerted by the liquid during transport can break the bag, as is clearly explained in lines 34-50 of column 1 of US-A-4,968,642 which names the same inventors and the same proprietor as US-A- 4,910, 147. For this reason US-A-4,968,624 describes a very complex rigid structure within which the bags containing the solutions have to be enclosed for their storage and transport. Again for example, reference can be made to the method of using those sterile crystalline antibiotics (in powder form) contained in single-dose form in glass bottles sealed by rubber plugs. To use such antibiotics, using a syringe a sterile solvent (water) is drawn from a vial (which has firstly to be broken or opened), then the solvent is fed into the bottle by piercing its plug with the syringe needle, the bottle is shaken to dissolve the antibiotic powder, and the solution formed in this manner is drawn into the syringe through the needle which passes through the plug of the bottle, after which the solution can be injected into the patient. Although this operation may be relatively simple to carry out by a user who has to prepare the solution and inject it only one or a few times a day, it becomes very demanding and costly in hospitals in which specialized personnel (nurses) have to repeat the same operation a very large number of times every day, with considerable time wastage, high cost and serious problems of maintaining sterility, these being enhanced by the need to dispose of a large number of empty glass bottles with rubber plugs, glass vials and miscellaneous packaging material. Again it should be noted that it is not possible to prepare solutions of antibiotics (for example in bags such as those described in US-A-4,910, 147) in suitable plants to then despatch them to hospitals, because such solutions remain unaltered only for a very short time, and then only if special care is taken for their preservation. In the light of the aforegoing, the main object of this invention is to provide a bag usable for preserving and transporting sterile products in powder form and for feeding into it a solvent to directly form a solution, dispersion or suspension of the powdered product directly within the bag under sterile conditions, the bag being provided with at least one port through which the entire solution or the like or a part thereof can be easily, quickly and safely withdrawn in order to be used. A further object is to provide a method which enables sterile products in powder form to be packaged in easily storable and transportable flexible bags, and further enables solutions or the like of such products to be subsequently formed directly within the bags when the solution is to be used. These and further objects are attained by a bag of polyolefin construction which is hermetically sealed at its periphery and has at least one port also of polyolefin construction defining a passageway the two ends of which open inside and respectively outside the bag, said passageway being closed by a breakable membrane forming part of the port and ensuring the maintaining of sterility within the bag, characterised in that the bag contains a sterile product in powder form, the bag capacity exceeding the directly usable volume of the final sterile product solution, dispersion or suspension obtained by feeding a liquid into the bag through said port and said membrane. The bag structure and its method of use will be more apparent from the ensuing description of a preferred embodiment thereof given by way of non-limiting example with reference to the accompanying drawings, on which: Figure 1 is a schematic front view of the bag, of which Figure 2 shows an enlarged partial section coplanar with that portion of the bag on which the bag access port is provided; Figure 3 is a section through the bag taken on the line 3-3 of Figure 1, the bag being shown filled only to a minimum extent with a product in powder form and with the port closed; Figure 4 is similar to Figure 3, but with the port open for feeding into the bag a liquid having a volume occupying only a part of the bag capacity; and Figure 5 shows the closed bag inserted into a further two bags used for its storage and its despatch to the powdered product user. Reference will firstly be made to Figures 1 to 4, which show a bag 1 constructed of polyolefin, preferably low density polyethylene, sealed hermetically along its entire periphery and having at one end a port 2 formed in one piece with and projecting from an elongate tapered body 3 from which there projects a further port 4. The ports 2 and 4 and the body 3 are constructed of the same material as the bag 1, the body 3 being incorporated into the peripheral bonding seam 5 of the bag 1 so that one end of the ports 2 and 4 opens inside the bag whereas their other end opens outside the bag. As can be seen from Figure 2 the ports 2 and 4 define conduits closed by respective membranes 6 and 7 respectively, which are formed integrally with the ports and are arranged to ensure sterile conditions in the bag when it contains the product in powder form, as explained hereinafter. From the figures it can also be seen that on the free ends of the two ports 2 and 4 there are applied protection plugs 8 and 9 respectively, which can be removed if required. Before bonding the bag 1 along its entire periphery it is sterilized (for example with β rays), then into it, using an automatic machine in a sterile environment, there is fed a mass of sterile product in powder form 10 which, as can be seen from Figure 3, occupies only a small part of the bag capacity. The powder can be advantageously fed through that end of the bag distant from the end comprising the ports 2 and 4, after which this end is heat-bonded. The described bag encloses and protects in a sterile environment the sterile product in powder form contained in it. This bag can be easily and economically stored and transported to the user by the producer who has packaged it. To make storage and transport very secure, the described bag 1 is preferably inserted into an intermediate bag 11 (Figure 5) also constructed of polyolefin, preferably high density polyethylene, and which after being sealed is inserted into an outer bag 12 composed of three layers of different materials welded together, of which the inner layer 13 is constructed of polyolefin (preferably high density polyethylene) or polyvinyl chloride, the intermediate layer is constructed of a barrier material (preferably aluminium), and the outer layer is constructed of polyolefin, nylon or polyester. The packaging of the bag 1 in the bags 11 and 12 is known, and is of the type illustrated in US-A-4,700,838, corresponding to EP-B- 201880. The nature of the barrier material in its general terms (additional to aluminium) can be as defined in US-A-4,910, 147. When the sterile product in powder form is to be used, the bag 1 is removed from the protection bags, the stopper 8 is unscrewed, and into the port 2 a perfuser is inserted so that its free end 16 fractures the membrane 6 (Figure 4). The perfuser is a well known device and will not be described for simplicity. Its end sealedly engages the cavity in the appendix 2, through which the desired quantity of water can be easily fed under sterile conditions into the bag 1 to form with the powdered product a solution 17 which fills only a part of the bag capacity. This merely partial filling of the bag 1 is necessary to enable the liquid in the bag to be energetically shaken in order to quickly and completely dissolve, disperse or suspend the product in powder form to make it suitable for use. One of the preferred uses of the described bag is to preserve and transport sterile crystalline antibiotics and to form injectable solutions thereof in hospitals and the like. To give a detailed practical example, a bag 1 is prepared from a sheet of low density polyethylene of 150 micron thickness, the bag having a height of 35 cm and a width of 45 cm. 300 g of an antibiotic in powder form are fed into this bag and preserved in a sterile environment. The bag 1 is sealed within an intermediate bag of high density polyethylene of 100 micron thickness, having a height of 40 cm and a width of 48 cm. The intermediate bag is then inserted into and sealed inside an outer bag of 43 cm height and 54.4 cm width formed from three layers joined together, the inner layer being formed of high density polyethylene of 0.075 mm thickness, the intermediate layer being formed of a sheet of aluminium of 0.01 mm thickness, and the outer layer being of polyester resin of 0.012 mm thickness. When the antibiotic is to be used, the inner bag 1 is removed from the intermediate bag 11 and outer bag 12 and 3000 ml of injection- quality water are fed into it via the described perfuser (Figure 4) to form a solution of the required concentration for the particular therapeutic dose, in this case 100 mg/ml . It is important to note that the antibiotic solution 17 occupies only a part of the bag capacity to enable the antibiotic to be quickly and completely dissolved by vigorously shaking the bag. The bag capacity is preferably between 1.5 and 2 times the volume of the solution to be prepared in it. The antibiotic solution obtained in this manner can be used directly, for example it can be transferred into sterile syringes each containing 30 ml of solution. The syringes can be filled in groups (for example 10, 20 or more syringes at a time) by automatic machines of known type which withdraw the solution through the free end 16 of the perfuser (by arranging the bag with the port 2 pointing downwards) used for feeding the liquid into the bag. If desired, individual doses of the antibiotic solution can be withdrawn through the port 4 (the presence of which is not strictly necessary but is preferred). To do this, the stopper 9 is removed, and a rubber plug 20 (which seals that part of the cavity of the port 4 external to the bag 1) and the membrane 7 are perforated by the syringe needle. When the syringe needle is removed, the solution is unable to flow from the bag 1, this being prevented by the rubber plug 20. If the syringes are not used within a short time after their filling, they can be preserved in a freezer and then be despatched to the user in hospital in controlled temperature containers. From the aforegoing description it is apparent that the antibiotic solution can be very easily and quickly formed at the desired concentration in a sterile environment, and that syringes can then be filled likewise easily and economically. By proceeding in the aforedescribed manner, very important advantages are obtained compared with traditional systems in that it is no longer necessary to preserve the sterile antibiotic in powder form in glass bottles, a considerable reduction in the risk of contamination of the final pharmaceutical product is achieved (with the traditional system, for each syringe the solution has to be prepared individually and be fed into the syringe in environments which are generally not sterile), and there is a considerable cost and ecological saving consequent on the fact that it is no longer necessary to use glass bottles, metal rings, rubber plugs (one for each bottle), glass vials for solvents, etc. All this leads to a considerable cost reduction, especially because a large number of specialized personnel are no longer required for preparing the individual antibiotic solutions, this being a very costly operation in hospitals or in those places in which a large quantity of antibiotic solutions has to be prepared. Very considerable advantages are obtained even if the sterile products contained in the bags are not pharmaceutical products but are other products in powder form to be dissolved or dispersed in various liquids for their use, such as cell culture media. In addition to the described bag, the invention also relates to the method for preserving and transporting sterile products in powder form and for dissolving or dispersing them in liquids under sterile conditions, as defined in the introductory part and in the claims accompanying this description.

Claims: Cl aims : 1. A bag for preserving and transporting sterile products in powder form and for forming solutions, dispersions or suspensions of said products therein, the bag being of polyolefin construction, being hermetically sealed at its periphery and having at least one port also of polyolefin construction defining a passageway the two ends of which open inside and respectively outside the bag, said passageway being closed by a breakable membrane forming part of the port and ensuring the maintaining of sterility within the bag, characterised in that the bag contains a sterile product in powder form, the bag capacity exceeding the directly usable volume of the final sterile product solution, dispersion or suspension obtained by feeding a liquid into the bag through said port and said membrane. 2. A bag as claimed in claim 1, characterised in that said polyolefin is low density polyethylene. 3. A bag as claimed in claims 1 and 2, characterised by being enclosed and sealed within an intermediate bag also constructed of polyolefin and inserted into and sealed within an outer bag composed of three layers of different materials bonded together, and of which the inner layer is of polyolefin or polyvinyl chloride, the intermediate layer is of a barrier material, and the outer layer is of polyolefin, nylon or polyester. 4. A method for preserving and transporting sterile products in powder form and for forming solutions, dispersions or suspensions of said products, characterised in that said products are enclosed and sealed within a sterile bag constructed of flexible material and provided with apertures closed by membranes through which a liquid can be fed into the bag, the minimum capacity of the bag being at least 1.5 times the total volume of the liquid plus the powder fed into the bag.

Inventors: DUSCI SERGIO, FALCIANI MARCO, DUSCI, SERGIO, FALCIANI, MARCO
Applicants: ACS DOBFAR SPA, DUSCI SERGIO, FALCIANI MARCO, ACS DOBFAR S.P.A., DUSCI, SERGIO, FALCIANI, MARCO
Application year: 1999
Main classification: A61J1
IPC codes: A61J1, A61J3