FR2846128A1 - Straw for cryogenic preservation of biological materials, e.g. semen, comprises an inner tube and a coaxial outer tube that carries identifiers, welded together at the ends - Google Patents

Abstract

Straw (1) for cryogenic preservation of biological material (A) comprises an inner tube (10) of biocompatible material and a coaxial outer tube (3), made of polymer, for protection and for carrying identifiers. The new feature is that (3) is at least as long as (10) and each end of (10) and the regions of (3) that surround (10) are flattened and bonded together.

Description

t Ù

  The present invention relates to a straw intended to receive a biological substance with a view to its conservation, in particular by freezing.

  Currently, the samples of liquid human biological samples which it is desired to keep, (for example and in a non-exhaustive manner of blood, urine or sperm) are collected in a tube provided with a stopper, for example a tube known under the trademark "CRYOTUBE", and this tube is

frozen in liquid nitrogen.

  However, such a tube has a relatively large diameter, of the order of one centimeter, so that the volume of samples therein is large and that the freezing obtained is not homogeneous at all points. the sample.

  Also known in the prior art, flakes used in particular in the field of artificial insemination to receive a determined amount of animal semen or in the field of biological analysis to receive a sample.

  A straw is a long and thin tube, fitted near one of its ends with a stopper and delivered to users after being sterilized.

  The user (insemination center, hospital, biological analysis laboratory) fills the latter with animal semen or any other liquid biological sample and then closes both ends by crushing them and then welding them, for example to the ultrasound or any other technique known to those skilled in the art. Then this straw is frozen for use or

of a future analysis.

  In order to be able to subsequently identify the straw and its contents, the operator in charge of filling it, before the freezing step, prints on the body of the straw certain information, for example the date of filling and a patient or procreator identification code

  when it comes to animal seed.

  A first technique for identifying these flakes consists in engraving certain identification characters, such as a bar code or a code number, using a laser, directly on the external wall of the flake. A polyvinyl chloride (PVC) flake, for example, lends itself well to this type of marking.

  A second technique is to replace laser engraving with ink printing.

  However, depending on the chemical nature of the material used to make this flake, certain components of the inks used 5 adhere less well to the material, which leads to less clear prints or more sensitive to erasure. In addition, the solvents present in the ink or the inks used can on the contrary diffuse through the thin wall of the glitter.

  and come and contaminate the biological sample contained therein.

  To solve this problem, we know from document EP10 0 562 947, a flake consisting of a tube whose ends are sealed and which is provided with an identification sleeve carrying inscriptions in ink, threaded onto

  this tube, between said end seals.

  This sleeve, the length of which is less than half and greater than a quarter of that of the tube which it surrounds, also has an internal diameter sufficient to allow it to slide around the tube, but nevertheless less

to the width of said seals.

  This glitter has several drawbacks. First of all, the identification sleeve constitutes a localized excess thickness of the wall of the tube, which leads to an inhomogeneous freezing of the sample which is there over the entire length of the straw. After defrosting, there is therefore a significant risk that the sample obtained will no longer be homogeneous, which may have a negative impact on the result of the tests.

  biological analyzes or the subsequent use thereof.

  In addition, the identification sleeve is not integral with the straw 25 and risks being torn off accidentally, so that the latter is then no longer identifiable. Finally, after freezing, the flakes are kept upright in a tank of liquid nitrogen, so that the identification sleeve will tend under the action of its own weight to slide towards the lower end of the straw, the operator being able to observe only

  the upper end of it. Consequently, even if this identification sleeve is colored for the purpose of rapid visual identification, the operator is obliged to remove all the glitter from the same storage tube in order to observe the color of the sleeves and recognize which one interested. However, it is preferable to avoid unnecessarily taking the flakes out at room temperature.

  The present invention aims to overcome the aforementioned drawbacks and in particular to provide a straw whose means of identification do not have a detrimental influence on the quality of the freezing of the biological substance which

is contained.

  Another objective of the invention is to provide an easily identifiable straw, even when it is stored vertically and an operator cannot

see only the end.

  Yet another object of the invention is to provide a protected straw so as to limit the risks of accidental breakage.

  To this end, the invention relates to a straw intended to receive a biological substance with a view to its cryogenic preservation, consisting of an inner tube made of biocompatible material, provided with an outer protection and identification tube, coaxial with said inner tube. and surrounding it, made in a

  polymeric material and supporting signs of identification.

  According to the invention, said outer protection and identification tube is of a length at least equal to that of said inner tube and each end of this inner tube and the outer tube area located opposite

  this end are flattened and welded together to form a weld.

  According to other advantageous characteristics of the invention, which are not limiting, taken alone or in combination: the outer tube is threaded around the inner tube; - The inner wall of the outer tube is locally deformed, so as to prevent the sliding of the two tubes relative to one another before the welds are made; - the inner tube and the outer tube are co-extruded; - The inner tube and the outer tube consist of one or more layers of material between which is interposed at least one layer of adhesive material; - the welds are autogenous welds; 30 - the identification signs are characters printed in ink or laser engraved; - the outer protection and identification tube is colored; the outer protection and identification tube has at least one non-colored zone allowing the viewing of said inner tube; the outer protection and identification tube is longer than the inner tube and at least one of the ends of the outer tube located beyond the ends of the inner tube is flattened and welded to itself so as to forming an end tab;

  - the outer protection and identification tube is made of polyvinyl chloride or polyethylene terephthalate.

  Other features and advantages of the present invention

  will appear from the following description of an embodiment thereof, the

  description being made with reference to the accompanying drawings in which:

  - Figure 1 is a longitudinal sectional view of a straw, before filling, the outer tube being threaded on the inner tube; Figure 2 is a view of the straw of Figure 1, the two ends of which have been flattened and sealed; - Figure 3 is a cross-sectional view, on a larger scale, of an alternative embodiment of the straw of Figures 1 and 2, wherein the inner and outer tubes are co-extruded; - Figure 4 is a longitudinal sectional view of an alternative embodiment of the straw of Figure 1; - Figure 5 is a perspective view of the straw of Figure 2;

  FIG. 6 is a view, on a larger scale, of the end of the straw taken along line VI-VI of FIG. 2.

  Figure 1 illustrates the straw 1 according to the invention, as it

  is sold, that is to say ready to be filled.

  It consists of a cylindrical inner tube 10, of axis of revolution X-X ', having two opposite ends 11 and 12 of circular cross section. As an indication, this tube 10 has a length of 133 mm and a

  outer diameter of about 2.9 mm.

  The inner tube 10 is made of a flexible plastic material so as to be able to deform at its two ends and to form welds and preferably a transparent plastic material so as to be able to visualize the content thereof.

  In addition, this plastic material must be biocompatible, that is to say chemically neutral with respect to the biological substance contained therein, and must have good resistance to thermal shock and to cryogenic temperatures close to 770 K. By way of example, the inner tube 10 can be made of chloride of

  polyvinyl (PVC) or polyethylene.

  In the vicinity of one of its ends, (for example the end 11 in FIG. 1), the inner tube 1 contains a stopper 2 consisting of an agglomerate of gelable powder 21 (of the polyvinyl alcohol type), interposed between two cotton thicknesses 20 and 20 '. This plug is breathable. When the biological substance to be stored in the straw comes into contact with the cotton 20 ′, it soaks it. Then, when it reaches the powder 21, the latter gels and solidifies,

  so that the plug 2 becomes tight.

  As is well known to those skilled in the art, the plug 2 performs two functions, namely to close one of the ends of the filled straw and to act as a piston for the evacuation of the biological substance from the

  glitter by the other end, when using it.

  An outer protection and identification tube 3 is mounted coaxially around the inner tube 10; it has two opposite ends of cross section

  circular referenced respectively 31 and 32.

  The outer tube 3 can be threaded around the inner tube 10 and its

  inner wall is then in contact with the outer wall of the tube 10. However, advantageously, the inner wall of the outer tube 3 can be locally deformed, for example by punching, so as to prevent this tube from sliding relative to the tube interior 10 and separates therefrom, before making the 20 end welds.

  The two inner 10 and outer 3 tubes can also be coextruded and each of them can consist of one or more layers of

  material between which is inserted at least one layer of adhesive material 6.

  FIG. 3 illustrates an example of a straw 1 obtained by co25 extrusion, comprising successively from the inside to the outside, the tube 10, a layer of adhesive material 6, a first layer 33 of material constituting a part of the outer tube 3, a second layer of adhesive material 6 and a second

  layer 34 constituting the other part of the outer tube 3.

  The outer tube 3 is made of a suitable polymer material 30 to withstand cryogenic temperatures (close to 770K) and to serve as

  support for identification signs as will be detailed later.

  According to the invention, the length of this outer tube 3 is at least the same as that of the inner tube 10 (see Figures 1 and 2), or even

  possibly higher, (see figure 4).

  In the first case, when closing the straw 1, the end 11 of the inner tube 10 and the end 31 of the outer tube 3 are flattened and welded together; the weld obtained bearing the reference 41. Similarly, the end 12 of the inner tube 10 and the end 32 of the outer tube 3 are also flattened and welded together to form a weld referenced 42. FIG. 4 illustrates an alternative embodiment in the second case, in which the length of the outer tube 3 exceeds that of the inner tube 10. In the example illustrated in this figure, one of the ends of the outer tube 3 (here the end 31) extends beyond from the end 1 1 of the inner tube 10, (on the left on

the figure).

  The welding 41 is carried out by flattening and jointly welding the end 11 of the inner tube 10 and the area 310 of the outer tube 3 located opposite this end 11. Furthermore, the end 31 of the outer tube 3 located beyond the end 11 is also flattened and welded to itself by

  so as to form an end tab.

  What has just been described for the end 31 of the outer tube 3 could also be produced at the opposite end 32 to form another

end tab.

  Advantageously, the welds 41 and 42 are autogenous welds, that is to say made without the addition of external material. They are carried out for example by ultrasound or by any other technique known to man.

of career.

  Axially, between the flattened weld 41, (respectively the weld 42), and the cylindrical portion of the outer tube 3 is a junction zone

  intermediate or throttle, referenced 36, (respectively 37).

  The identification signs 5 of the glitter are characters printed in ink or laser engraved on the outer surface of the outer tube 3, it

  it is for example a bar code 51 or a code number 52, (see FIG. 5).

  These identification signs could also be produced on the end tab 35.

  Advantageously, the outer identification tube 3 is colored, that is to say tinted in the mass, so as to further improve the identification of the

glitter 1.

  When the outer tube 3 is colored, it may have one or more non-colored zone 30 (see FIG. 3) making it possible to see the inner tube 10 and its contents, if this tube 10 is transparent.

  This non-colored zone 30 is in the form of a longitudinal stripe.

  The number of scratches can also constitute a sign of identification of the glitter 1.

  As the polymer material of the outer tube

  identification 3 having simultaneously sufficient resistance to cryogenic temperatures, an ability to withstand printing in ink and sufficient flexibility for making the end welds, polyvinyl chloride (PVC) may be used, for example, or polyethylene terephatalate 10 (PET).

  The outer identification tube 3 extending over the entire length of the inner tube 10, the straw 1 according to the invention makes it possible to obtain uniform freezing of the biological sample over the entire length.

of this glitter.

  In addition, the outer protection and identification tube 3 being welded by its two ends to the inner tube 10, it cannot be accidentally torn from the latter and the identification of the straw 1 is ensured at all times.

during its use.

  In addition, the outer tube 3, in particular when it is colored, facilitates rapid identification of the straw 1. In fact, an operator who observes the straw 1 from its end (as shown in FIG. 5 and as is when it is in a liquid nitrogen tank), can see on either side of the weld 42, the colored intermediate zone 37. The latter constitutes

  also an additional visual identification mark.

  It would also be possible to very slightly bend the ends of the

  inner 10 and outer 3 tubes at the welds 41, 42, (that is to say up or down relative to the representation of FIG. 2), so that they are no longer strictly in the 'X-X axis'. Thus, an operator observing the straw 1 at the end would more easily see the color of the outer tube 3.

  Furthermore, the outer tube 3 protects the inner tube 10 over its entire length and limits the risk of it breaking.

  Finally, it should be noted that the outside diameter of the outside tube 3 is close to 3.2 mm, that is to say less than the outside diameter of the sheaths with identification sheath 35 of the prior art. This reduces the volume occupied

  by a straw in the storage tanks and consequently increase the number of straws which can be stored in the same volume.

Claims (11)

  1. straw (1) intended to receive a biological substance with a view to its cryogenic preservation, consisting of an inner tube (10) made of biocompatible material, provided with an outer tube (3) for protection and identification, coaxial with said audit inner tube (10) and surrounding it, made of a polymer material and 5 supporting identification signs (5, 30), characterized in that said outer protection and identification tube (3) is of a length at least equal to that of said inner tube (10) and in that each end (11, 12) of this inner tube (10) and the area (310, 31, 32) of the outer tube (3) located opposite this end (11, 12) are flattened and welded together to form a weld 10 (41, 42).   2. A straw according to claim 1, characterized in that the outer tube (3) is threaded around the inner tube (10).   3. A straw according to claim 2, characterized in that the inner wall of the outer tube (3) is locally deformed, so as to prevent the sliding of the two tubes (3, 10) relative to each other before the realization of welds (41, 42).   4. A straw according to claim 1, characterized in that the inner tube (10) and the outer tube (3) are co-extruded.   5. A straw according to claim 4, characterized in that the inner tube (10) and the outer tube (3) consist of one or more layers of material (10, 33, 34) between which is interposed at least one layer of adhesive material (6).   6. A straw according to claim 1, characterized in that the welds (41, 42) are autogenous welds.   7. Glitter according to claim 1, characterized in that the identification signs (5) are characters (51, 52) printed in ink or engraved laser.   8. A straw according to claim 1, characterized in that the outer tube (3) for protection and identification is colored.   9. A straw according to claim 8, characterized in that said outer tube (3) for protection and identification has at least one non-zone   colored (30) allowing the viewing of said inner tube (10).   10. A straw according to claim 1, characterized in that the outer tube (3) for protection and identification is of a length greater than the inner tube (10) and in that at least one of the ends (31 , 32) of the outer tube (3) located beyond the ends (11, 12) of the inner tube (10) is flattened and welded   on itself so as to form an end tab (35).   11. A straw according to claim 1, characterized in that the outer tube 5 (3) for protection and identification is made of polyvinyl chloride or made of polyethylene terephthalate.