Method of forming a connection between two sealed condiutsusing radiant energy

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NORWAY [NO] [Β] (Π) INTERPRETATION NO. 149802 [01 (45) PATENT NOTIFIED a ?. Jrøl 1984 (5!) Int · Cl?_{A 61} | Y | -_5/14

<td>BOARD</td><td> (21)</td><td>Patent application no.</td><td> 783523</td>

<td>FOR THE INDUSTRIAL</td><td> (22)</td><td>filed</td><td> 18.10.78</td>

<td>DEFENSE</td><td> (24)</td><td>Løpedag</td><td> 18.10.78</td>

(41) Widely available from 20.04.79 (44) Application submitted, explanatory note published 19.03.84 (30) Priority requested

19.10.77, USA, 843608 (54) The invention relates to a method of forming a connection between two sealed wires and a connector for carrying out the method.

(71) (73) Seeking / Pafenlhaver

BAXTER TRAVENOL LABORATORIES. INC.,

One Baxter Parkway,

Deerfield, IL 60015,

USA.

<td>(72) Inventor</td><td>DANIEL B. GRANZOW, Arlington Heights, IL, GARRY L. CARTER, Hoffman Estates, IL, DAVID AMMANN, Linden'hurst, IL, USA.</td>

<td>(74) Agent</td><td>A / S Bergen Patent Office, Bergen,</td>

(56) Cited publications

No.

BACKGROUND OF THE INVENTION The present invention relates to a method of forming a connection between the interior of two sealed wires and a connector for carrying out the method.

The need to provide a sterile, sealed connection between a pair of wires is particularly evident in the field of blood and blood component processing, and in other areas where a sterile connection between containers is desirable.

In the area of ​​blood treatment, it may be desirable to use only half of a unit of blood in a bag, etc. When this occurs, it is common to discard the unused portion of the blood unit within a day after access to the bag is made, even when efforts are made. to maintain sterility by using commonly accepted aseptic methods for access to the blood bag. This is so because only one or two airborne bacteria will be able to multiply in the stored blood and cause a risk of sepsis if the bacterium is allowed to multiply for a period of more than a few hours and the blood is then administered to a patient.

Consequently, in order to eliminate the need to dispose of the remainder of a unit of blood when only part of the unit is needed, or for many other reasons why sealed sterile access between different containers is desirable, considerable research for the development of aseptic fluid transfer systems. Eg. For example, US-A-4,022,256 discloses a sterile connection device in which a heat-meltable tube is provided with an inner layer of plastic material which does not melt at the temperature used. A compound which is claimed to be sterile is produced by the use of a heat punch which presses the non-meltable layer through the melting outer layers of the tube to form a sterile connection between the two tubes, wherein the melted layers of the tube form a single, perforated layer.

The invention according to the aforementioned US patent requires a special heat punch to push the non-melting layer through the fusible layer in the conduits. In addition, in the embodiment shown in the patent, the fusible material is pressed against the heat stamp. Adhesion between the fusible material and the heat punch when the punch is pulled away after printing can cause a flake to form in the connection or at least severely weaken it.

According to the present invention, the use of a heat and pressure die to eliminate a sterile connection between two wires is eliminated. Instead, radiant energy is used to selectively melt a portion of the conduit wall without any physical contact between a die or the melting portion.

The method is characterized in that a radiation energy absorbing conduit wall portion at the end portion of the conduits is selectively melted by the application of radiant energy having an intensity and duration sufficient to cause the radiation energy absorbing wall portion to fuse each other into the conduit thereby forming a through opening .

In addition, according to the invention, a mechanical connector may be provided between the two conduits to protect the molten sterile connector from being torn up mechanically.

The connector is characterized in that it comprises

a) a housing having a first radiation energy absorption capability and adapted to form a connection between the end portions of the two conduits; and

b) a wall portion having a second radiant energy absorbency greater than the first absorbency, wherein the wall portion is disposed within the housing and normally separates the interior of the two wires from each other and is adapted to form a through opening by heating to the melting temperature with radiant energy.

According to the invention, a connection, especially a sterile connection, can be formed between sealed wires. Each conduit is provided with a thermoplastic wall portion which preferably has a melting temperature of at least 200 ° C and which is opaque for the particular radiant energy to be used. This melting temperature, which may be a temperature range, can be determined e.g. by means of differential thermal analysis.

To prepare the sterile compound, the opaque, thermoplastic wall portions are brought into contact with one another face to face. The opaque wall portions are exposed to sufficient radiant energy to melt together and to open an opening through the molten wall portions. This causes sealed connection between the wires.

Preferably, the opaque thermoplastic wall portions are circumferentially enclosed by a transparent, rigid sleeve which typically forms the end of a conduit. The rest of the cord can be flexible if desired. The rigid sleeve is transparent and is made of a material which does not soften under the particular radiation conditions used in the process. Instead, the radiant energy can pass through the transparent sleeve, which preferably encloses and protects the opaque wall portions when brought together face to face, so that it is primarily the opaque front wall portions that are heated to their melting point rather than the transparent sleeve that supports and protects the opaque wall. wall sections.

When the opaque wall portions melt, they preferably merge into a single sealed mass, and due to the melt a central opening is formed in the molten opaque thermoplastic wall portion. Any bacteria located on the outer surfaces of the opaque wall portions are trapped in the molten mass and are preferably killed when exposed to the melting temperature in the opaque wall portions, the melting temperature being preferably of the order of 200-250 ° C.

The radiation energy can be supplied to the system using visible, infrared, ultraviolet or radio frequency energy as desired. By the term opaque is meant that opaque wall portions are capable of absorbing a high percentage of the particular radiation energy to which they are exposed. The term transparent means that a lower percentage of the radiant energy is absorbed. Focused, infrared radiation energy is particularly desirable for use.

Lasers can, if desired, also be used to generate the radiation energy.

The opaque wall portions may be biased by uniaxial or biaxial orientation or with radiation stress patterns, to facilitate the formation of the central aperture in winter when the opaque wall portions are sealed together. Unprecedented wall portions may also be used, whereby the central opening is formed by cohesion during melting.

The invention will be explained in more detail below with reference to the accompanying drawings, in which:

FIG. 1 is a view of a pair of ends of conduits whose other ends may be connected to a pair of blood bags or the like, each end of which is terminated by a sleeve enclosing an opaque, thermoplastic wall portion of the invention.

FIG. 2 is an enlarged view, partly as a longitudinal section, of one of the conduit ends shown in FIG. 1.

FIG. 3 is an elevational view of the two ends of FIG. 1 after these are joined together so that the opaque wall portions face each other face to face, and further schematically shows the step of exposing the opaque wall portions to sufficient radiant energy to merge and open an opening.

FIG. 4 is an enlarged longitudinal section of the device of FIG. 3 before being exposed to the radiation.

FIG. 5 is an enlarged longitudinal section of the device of FIG. 3 after it has been exposed to the radiation.

Reference is made to the drawings in which conduits 10, 12 comprise flexible portions 14, 16, one end of which may be connected to a conventional blood bag 17, 19 or other container.

Sleeves 18, 20 are made of transparent, high-melting plastic material such as Lexan, a polycarbonate material. Each sleeve defines a hollow inner chamber 21 which communicates with the bores of the tubes 14 or 16, plus a pin 22 and a slot 24. Both the pin 22 and the slot 24 are arranged asymmetrically on the sleeve so that each pin 22 can fit into a corresponding slot 24 in a completely similar sleeve as a usually permanent snap lock. Each pin 22 may be held in place in the slot 24 by a hook action of a bar 26.

Accordingly, a pair of sleeves 18, 20, when joined together, can only be separated by considerable effort. Preferably, an expanded portion 28 of each pin 22 is sized to form abutment against the inner wall of the slot 24 of the second sleeve to make separation even more difficult by reducing the capability of the pins 22 to bend backward.

Each sleeve 18, 20 is provided with an opaque wall portion 30 which may be made of a thermoplastic material having a melting temperature of preferably at least 200 ° C.

Eg. For example, polycarbonate materials such as Lexan or polysulfone materials such as Udel or Radel can be used. Polyether sulfone materials can also be used.

The thermoplastic, opaque wall portion 30 usually contains a filler such as carbon black to make it opaque, although other desired fillers which absorb the type of radiant energy to be used can be used as a replacement for carbon black, e.g. iron oxide, manganese dioxide, etc.

The opaque thermoplastic wall portion 30 is shown as a disc which is preferably thinner in its central portion 32 than in its circumferential portion. The disc 30 can be attached by ultrasonic welding or along its circumference to the sleeve of a recess 34 therein, and it is shown slightly bulging outwards, to provide good pressure contact between pairs of opaque wall portions facing each other, as shown in FIG. 4. An annular groove 33 provides space for the plastic in the wall portion to flow when the opaque disc is placed in the transparent sleeve.

Fig. 4 also shows how the pin 22 fits into the opposite slot 24 of the second sleeve so that connection is made between the respective sleeves, with the opaque wall portions pressed together and enclosed protectively by the respective sleeves.

After the sleeves 18, 20 are joined, they are irradiated with radiant energy of a type absorbed by the particular opaque wall portions used. In particular, infrared radiation is a preferred form of radiation energy. This can, for example. is produced by two 1-50W Sylvanian lamps with an elliptical reflector (model DJL). This produces focused infrared light which can be focused towards the centers of the wall portions 30 which form against each other so that they heat rapidly over a period of preferably from ten to twenty seconds, largely to the melting point, resulting in the respective wall portions. 30 are fused together and the formation of the opening 36, upon cessation of tension or simply due to cohesive forces, through the wall portions 30.

Bacteria trapped on the wall portions are killed by heating the wall portions 30 to their melting temperature and are further trapped when the molten material in the wall portions 30 solidifies again. This results in the formation of a connection between the sterile flow channels 21, while still maintaining the sterility of the channels.

The molten wall portions 30 fuse together to form a hermetic seal around the opening 36, to prevent violations of the sterility of the flow path. At the same time, the sealing line 38 between the respective membrane wall portions is protected against mechanical breakage by the generally permanent connection between the respective sleeves 18, 20.

Alternatively, if it is desirable to use radio frequency energy or radiation energy, the opaque wall portions 30 may be made of plasticized polyvinyl chloride, while the rest of the sleeves 18, 20 may be made of a plastic material which is relatively inert to radio frequency energy, e.g. polypropylene, polyethylene, poly (vinyl chloride-vinylidene chloride), or a similar material that is not substantially heated when exposed to radio frequency or other high-energy, high-frequency electric radiation fields.

Thus, according to the invention, a sterile compound, e.g. between a full and an empty blood bag by simply connecting a cord from each of the bags to each other, each cord being provided with the sleeve 18, 20 of the invention. The joined sleeves may be subjected to focused infrared radiation for melting of the opaque wall portions and fusion thereof as well as forming the aperture through the portions. Thus, a sterile compound is provided through which a portion of the blood in the full blood bag can be fed to the empty bag for use. Thereafter, the connection between the bags may be broken in the usual manner by sealing one or both flexible lines 14, 16, which run from the blood bag to the sleeves 18, 20, in a Hematron heat sealing apparatus. Thereafter, the blood bags can be transported to the desired place of use, or returned for long-term storage.