EP0897517B1 - Process and device for freezing of cell suspensions - Google Patents

Description

The invention relates to a method for freezing cell suspensions as well an apparatus for performing this method.

The invention relates in particular to human cell suspensions and will described in more detail below with reference to such substrates, although the invention is also applicable to cell suspensions of other origins. These suspensions contain living cells, which are usually human blood. The aim of the method according to the invention in such embodiments is to freeze such cell suspensions so deeply that on the one hand as possible many vital cells are preserved and on the other hand to avoid their use from preserved blood if necessary to a person's own blood can be used.

It is already known (DE 29 29 278 C2), cell suspensions of the type mentioned by freezing that from components of human blood and an antifreezing agent existing cell suspensions, which in certain Volumes of the frozen goods in preferably flexible plastic bags form, introduces into a chamber and in this according to a predetermined temperature / time function frozen. The prior art assumes that in such suspensions, a functional relationship between the relevant Cooling rate and the proportion of after thawing in the suspension still contains vital cells, so it depends on one before Comply with the cooling rate determined over time as closely as possible. In devices, the extremely high ones, however, are supposed to work according to this procedure Cooling rates pose significant difficulties, which leads to that except on a laboratory scale larger volumes as they are treated on an industrial scale should not be able to be frozen or not be optimally frozen.

In fact, such processes have so far been technically so (DE 44 37 091 A1) carried out that one in aqueous solution mostly with the addition of an anti-freeze additive cell substance contained in suspended form with their Flat bags made of low-temperature resistant plastic in a closed Container or an open jig and then into one Container immerses the freezer for freezing, preferably liquid Nitrogen. The container or the jig make a first approximation a press because it holds the flat bag between its lids or clamp between plates using a mechanical gear. Thereby the flat elastic bag becomes an essentially homogeneous plate shape achieved so that on the one hand a large surface / volume ratio is achieved and on the other hand geometric inhomogeneities such as folds or Bulges are avoided, so that an improved heat transfer is achieved is, but at the same time an uncontrolled cooling by geometric Inhomogeneities of the flat bag can be reliably prevented. In addition allows the flat bag to be pressed into a thin, homogeneous plate shape frozen content, which in turn saves space and one rapid reheating permitted if necessary. Serve as pressing tools plane-parallel plates, their mutually facing surfaces as cooling surfaces serve that act on the flat sides of the flat container when the press is closed. The plate sides opposite the cooling surfaces act directly after immersing the press in the container liquid refrigerant. A mechanical system of the press ensures that the pressing pressure Maintain during freezing until the flat bag is removed becomes.

These known freezers for suspensions of living cells in practice, however, lead to some difficulties. The combination of the Flat bag press with a container containing the liquid refrigerant assumes that this is for immersion and removal from the refrigerant is open. Since the refrigerant is usually liquid If nitrogen is involved, risks arise. They result from the possible Nitrogen overload in the room air and from the risk of injury from unwanted Skin contact on cold surfaces and liquids.

In addition, the services are performed with such presses Freezing process and thus the degree of utilization of the modules described of the known freezers insufficient. Because of that their use is limited to the laboratory scale, the operating costs considerably. They do not only result from the inevitable with the diving process associated evaporation losses on refrigerant and the only limited possible thermal insulation to avoid energy losses. This Difficulties also lead to the use of supercooled refrigerant, especially excluded from supercooled liquid nitrogen, though this improves the heat transfer under certain boundary conditions could be achieved on the frozen goods.

FR 2 632 391 describes a method for freezing Cell suspensions are known, in which the in a packaging enclosed cell suspensions between contact areas, which are brought to a low temperature, thereby be frozen that the refrigerant packaged the heat Absorbs cell suspensions. From the document mentioned however, no measures are evident by means of which achieved a particularly high and controlled cooling rate could be. In particular, the use of a supercooled Refrigerant not disclosed.

In contrast, an object of the invention is a To provide procedures in which one is simple Way controllable and - if desired - very high cooling rate can be achieved, and this under Use of a supercooled refrigerant.

From FR 2 632 391 a device for Implementation of the method described above is known with cooling plates through which a refrigerant flows facing sides serve as contact areas and one Limit the gap in each of which is a cell suspension protrudes. However, the known device has no measures to improve the cooling capacity or the cooling capacity control as well as for easier handling.

Another object of the present invention is accordingly therein a device for performing the invention Provide process in which the cooling capacity and their control and manageability improved are.

On the one hand, the tasks mentioned are solved with a Method according to the subject matter of patent claim 1. Appropriate configurations result from the subclaims 2 to 8.

Furthermore, to solve the above-mentioned tasks 9 shows a device for performing the aforementioned method suggested. Appropriate configurations of this device result from subclaims 10 to 29.

In the cryopreservation of human red blood cells with hydroxyethyl starch as an anti-freeze additive, the invention proceeds from the relationship between the mean cooling rate B during freezing and cell recovery S (= stability of the thawed cells in isotonic saline solution), as determined experimentally:

The invention now takes advantage of the fact that in a band of cooling rates a flat maximum of cell recovery between 150 and about 350 K / min (cell recovery) occurs. It takes into account that the cell survival rate at too high cooling rate decreases again. The design is therefore in accordance with the invention the method and a device operating according to this always a special one Cooling process adapted. Although in the literature for conservation individual cell types cooling protocols according to the status described at the beginning the technology published is generally not the cooling process, but only the cooling rate to be set is important. Erythrocytes require high cooling rates, temperature control according to a special freezing protocol is not required in the preservation process.

According to the invention as set out in claim 1, that according to the invention the frozen goods, in which one generally assume can only have one type and size of cell suspensions in bags should be frozen (e.g. either erythrocytes or stem cells or Platelets or leukocytes etc.), which are already at the low for the cooling rate bring brought necessary temperature brought contact surfaces, so that only the individually present frozen food with its content of cell suspension needs to be cooled. You tune the cooling surface to that Cooling rate. Since according to the invention the coolant is supercooled and that Process is carried out so that it is the heat from the frozen goods until boiling picks up over the contact areas, bubbles form in the process Refrigerants which, however, collapse again when they rise in the refrigerant, i.e. recondense. The method according to the invention therefore leads to the absorption of heat from the frozen food on the coolant side of the contact surfaces for net vapor formation from the coolant.

This new process is compared to the devices that use the flexible frozen food clamp and then immerse in containers with liquid refrigerant, considerably more economical because in particular the repeated cooling and heating the bag chucks and all others with Disadvantages associated with diving the frozen goods are eliminated. The new process also enables optimal cooling rates for a maximum Yield of living cells is a prerequisite. This is a consequence of the high Cooling rate, which is a complete removal of the enthalpy of the frozen food and the Flow in the refrigerant during the cooling process allows through the described bubble formation and bubble recondensation occurs in the refrigerant.

Since the inventive method the heat transfer from the frozen goods on the contact surfaces and from these to the refrigerant with a high cooling rate enables without the cooling according to an exact cooling protocol needs to be carried out, but also within the framework of the procedure The procedure can be carried out at its practical level Usable according to the type of frozen food and according to dimensions of the contact surface to be matched to the cooling rate. Frequently, i.e. especially in the preferably for the invention into consideration upcoming cooling of blood supplies in flexible plastic bags then both the cooling rates and the sizes of the contact areas given. If the method according to the invention is then used, the result is a significantly higher cooling rate than previously. On the other hand and according to claim 3, the heat transfer can also in optimize the other direction by changing the thickness of the frozen food between the contact areas increased and thereby higher cooling rates, which the invention enables, for this purpose, the previously experimentally determined cooling rates nevertheless to adhere to or even enlarge.

With the features of claim 4, the cooling rate can be increased because this dissipates larger amounts of heat from the frozen goods into the refrigerant become. This can include can be achieved with the features of claim 6. The heat transfer into the freezing agent can also be improved, which among other things. is made possible with the features of claim 7.

If the process according to the invention is used on an industrial scale, it also offers the advantage of optimal use of the refrigerant. In particular enables the procedure to be carried out according to claim 5 then in such a way that that of the refrigerant over the contact surfaces Amounts of heat absorbed from the circulating refrigerant be removed by hypothermia before the refrigerant hits the contact surfaces acted upon again. Such, essentially closed The coolant circuit then only needs to replace small amounts of refrigerant, which can arise from inevitable losses in the circuit.

The embodiment of the invention is also suitable for the industrial scale Procedure, as this is the heat of the frozen food and the subsequent installation of the contact surfaces on the in flexible packaging located frozen food uses an even, wrinkle-free deformation of the frozen food to a constant, even layer thickness between to reach the contact areas. This is one of the prerequisites for one even deep-freeze with the highest possible proportion living cell substance after thawing.

Fig. 1

perspektivisch und in abgebrochener Darstellung eine erste Ausführungsform einer Kontaktfläche mit deren Kühlung durch ein flüssiges Kältemittel,

Fig. 2

eine erste Ausführungsform einer erfindungsgemäßen Vorrichtung in zwei übereinander dargestellten Betriebsphasen, wobei ein Teil der Vorrichtung im Schnitt wiedergegeben ist,

Fig. 3

eine zweite Ausführungsform der Kontaktflächen mit ihrer Kühlung, die im wesentlichen im Horizontalschnitt wiedergegeben ist,

Fig. 4

eine Einzelheit der Fig. 3 an der dort bezeichneten Unterkante,

Fig. 5

eine weitere Ausführungsform der Erfindung unter Darstellung des Kühlmittelkreislaufes, wobei die Kontaktflächen und die ihnen unmittelbar zugeordneten Teile im Schnitt dargestellt sind,

Fig. 6

eine weitere Ausführungsform der erfindungsgemäßen Vorrichtung, deren Teile, wie links in Fig. 5 dargestellt, wiedergegeben sind, und

Fig. 7

eine weitere Ausführungsform der Erfindung, die in Draufsicht und teilweise im Schnitt wiedergegeben ist.

Other advantages of the invention result from the following description of several exemplary embodiments of devices for carrying out the described method with reference to the figures in the drawing; show it

Fig. 1

a first embodiment of a contact surface with its cooling by a liquid refrigerant, in perspective and in broken form,

Fig. 2

1 shows a first embodiment of a device according to the invention in two operating phases shown one above the other, part of the device being shown in section,

Fig. 3

a second embodiment of the contact surfaces with their cooling, which is shown essentially in horizontal section,

Fig. 4

3 at the lower edge designated there,

Fig. 5

a further embodiment of the invention showing the coolant circuit, the contact surfaces and the parts directly assigned to them being shown in section,

Fig. 6

a further embodiment of the device according to the invention, the parts of which, as shown on the left in FIG. 5, are shown, and

Fig. 7

a further embodiment of the invention, which is shown in plan view and partially in section.

2, the frozen goods consist of a cell suspension, which is packed in flexible plastic bags 1. These bags are by packaging in a plastic film 2 as packaging material without Loss of their tightness deformable and take on their suspension a movable conveyor of a continuous conveyor 3, as in the illustration above 2 shows a teardrop shape in the vertical cross section, because the cell suspension is liquid. Freezing takes place between contact surfaces of chambers 4, 5, the mode of operation of which is explained in detail below becomes. The two chambers are essentially the same design and are first described in more detail with reference to the details shown in FIG. 4.

Thereafter, each chamber 4, 5 is essentially a hollow body 6 semi-cylindrical shape with a rigid outer wall 7, an inner heat-insulating lining 8 and an inner lining 7a. In In the exemplary embodiments, each chamber 4, 5 has a flat inside 9. This is closed with a flat cooling plate 10, 11. In the shown in Fig. 2 Device serve the opposite outer sides of the cooling plates as contact surfaces 12, 13.

As shown for example in Fig. 4, these act on the two flat sides 14, 15 of each plastic bag 2. According to the illustrated embodiment each cooling plate 10, 11 is ribbed on the inside. By the majority of these Ribs 16, the respective surface of the cooling plates on the coolant side is considerable increases, which causes the heat transfer from the contact surfaces to the Coolant is optimized. The cooling plates are with the inner molded body walls 7a of the chambers screwed and also point in the rib bases 17 a coating 18, which consists of a microporous material. As a result, the heat transfer surfaces are enlarged further their flow of liquid from the chamber inside 9 Degree of heat transfer increased, and also on the coolant side Contact surfaces 12, 13 germs for the bubble boiling of the coolant are available be put.

The options deviating from this, the degree of heat emission, are not shown increase in a different way, for example by Surfaces anodized to coolant or color them black. On the other hand the contact surfaces 12, 13 of the cooling plates 10, 11 are good heat conductors executed. For this purpose you can, for example, from a corresponding Material, e.g. from copper, can be obtained or receive a coating, both with the aim of reducing the surface roughness.

Further details of the construction of the chamber are shown in FIG. 1 in Connection with FIGS. 2 and 3. Then everyone is in the interior Chamber an intermediate wall 19 which is substantially up to the height of the contact surfaces or the measures on the cooling surfaces sufficient to enlarge of the heat emissivity can be taken. In the embodiment 2 is a coating 18 made of microporous Material. The partition divides an isolated, the refrigerant supply line 20 in the chamber from a space 21, into which the supercooled coolant flows and the associated contact surfaces 12, 13 at the correspondingly low temperature before touching enters with the plastic bag. If this is the case, a bubble boil sets in a, the schematic in the lower part of FIG. 2 with the gas bubbles formed is shown. However, these gas bubbles become essentially without net vapor formation recondenses, which is due to the supercooling of the coolant. Only a small part of the gas exits upwards and is discharged from the mouth a gas recirculation line 22 included in certain embodiments the device according to the invention in a circuit of the coolant leads back. Liquid coolant exceeds with continued supply of supercooled coolant through the feed line 20, the upper edge 23 the partition that serves as a weir. A level control, the schematic Shown at 24 is a return line 25 in above the mouth a coolant plenum 26 of each chamber a certain height of the drain Coolant upright. Another feed line 27 carries more liquid Coolant into the collecting space 26 as soon as the one flowing out of the space 21 The amount of coolant is no longer sufficient. In this way it is largely automatic operation possible with constant quality of the frozen goods.

While in the embodiment of the device according to the invention 2 and 3 a practically determined by the supercooling of the coolant Cooling rate is achieved, the embodiment of FIG. 1 has the advantage that the cooling rate is also controlled by adding heat to the contact surfaces can be used even though a supercooled coolant is used. To for this purpose, the reinforced cooling plate 10 of meandering hot gas channels 28 or with electrical heating of heating wires. The contact area 12 can therefore be brought to a higher temperature if necessary. It also has a cooling plate which, like the cooling plate 6 shown, has a comparative character has large mass due to its wall thickness, an additional Heat storage capacity that the temperature increase of the cooling plate during freezing of the refrigerated goods.

The chambers 4, 5 and their individual parts described above are part of one Device (Fig. 5) with which flexible plastic bags in large numbers and especially on an industrial scale, rationally using the described method manipulated to freeze them. The manipulator shown serves this purpose 29, the two chambers 4, 5 combined, which are arranged so that their Cooling plates 10, 11 are vertical, so that the contact surfaces 12, 13 in are arranged substantially vertically. The chamber 4 is stationary, while the chamber 5 perpendicular to the contact plate 12 using the piston rod 30 of a double-acting working cylinder and a lever gear in is movable in two positions. A gap opens in the position shown 32, in which the plastic bag to be frozen finds 1 place. In the other Position closes the gap 32. There is a flexible plastic bag between the contact plates 12, 13, this is up to a certain, i.e. predetermined layer thickness compressed and only then deep-frozen. This Position moves the movable chamber 5 after retracting the piston rod 30 in the working cylinder 31. However, the packaged frozen food already has the required layer thickness when inserted into the gap 32, so that from the Share 30 and 31 existing chamber drive only for creating the Contact surfaces 12, 13 to the frozen goods.

The coolant is circulated through the chambers and a cooler 33, which cools the already liquid refrigerant. A pump M promotes the heated Coolant using parallel return lines from the coolant side Compartments 26 and 35 in the cooler 33, from which the supercooled Coolant through parallel feed lines 20 and 36 into the interiors 21 and 37 of the chambers is promoted. The fill level control 24 controls a valve 38, which controls the supply of coolant to compensate for coolant loss.

The coolant is controlled by the fill level control 24 by a Valve 38, which the supply of coolant to balance Coolant loss replaced. The coolant vapors pass through parallel Return lines 22 and 39 in a manifold 40, which also is valve-controlled and corresponds functionally to a line 41 which gasifies Coolant discharges from the cooler 33. Hoses as line connections between the two chambers allow their relative movement due to their flexibility perpendicular to the main surfaces of the frozen goods.

The embodiment of a two-chamber manipulator 41, which is shown in Fig. 6 differs from the manipulator designed for larger outputs 29 of FIG. 5 by a simplified management of the coolant for a common feed line 20 in the one-piece interior 43 of the fixed Chamber 4 leads, which in turn via its return line 25 initially connected to the movable chamber 5 or its feed line 36 is. The fill level control 24 controls the inflow of the coolant into both Chambers 4, 5, from which only the coolant vapors via the return lines 22 and 39 deducted and replaced by the valve 37 from the feed line become.

The embodiment according to FIG. 7 shows the two-chamber manipulation 43 in a thermally insulated housing 44, which also the continuous conveyor 3rd completely encloses, only necessary for the cooling chamber circuit Lines 45 for feeding the coolant, 46 for return to the subcooler 33 and out to replace the evaporated coolant at 37 are. In this way an optimal use of energy is achieved.

In this embodiment, the insertion and removal of the Plastic bag 1 containing the cell suspensin an entrance lock 47 and an exit gate 48 is provided. To the outside, these locks are included Locks 49 and 50 are provided while accessing the bicameral manipulator 43 realized by mutually operated sliders 51 and 52 is. The continuous conveyor leads out of the closable with the slides 51 and 52 Interior 53 of the thermally insulated housing 44 into the two lock chambers 47 and 48 and has a rotating conveyor element 54 with a drive and a deflection device 55, 56 and auxiliary guides 57 and 58, which the slip of the conveyor on the drive and deflection devices Avoid 55 and 56 by increasing the wrap angle so that the rotating conveyor can be a rope or chain conveyor on which the Plastic bag 1 can be attached.

• Öffnen der Eintrittsschleuse 47, was durch einen Knopfdruck ausgelöst werden kann;
• Einlegen des Beutels bei geöffnetem Verschluß 49;
• Schließen des Verschlusses 49 durch Knopfdruck, worauf das Programm für die nachfolgenden automatisch ablaufenden Schritte ausgelöst wird;
• Trocknen der in der Eintrittsschleuse 47 enthaltenen Luft durch einen Klimatisierungsschritt zur Reduzierung der Luftfeuchte in der Schleuse auf Null;
• Öffnen des Schiebers 52, d.h. das Zugangs zum Zweikammermanipulator;
• Transport des Kunststoffbeutels 1 aus der Eintrittsschleuse 47 in den Zweikammermanipulator;
• Schließen des Schiebers 52 und damit der Eintrittsschleuse 47;
• Ausrichtung des Kunststoffbeutels 1 zwischen den Kühlplatten der beiden Kammern;
• Anpressen der Kühlplatten in ca. 0,5 Sekunden oder schneller auf einen voreingestellten Anpreßdruck an den Beutelflachseiten 14 und 15;
• Wärmeabfuhr aus dem Beutel zum Abkühlen und Gefrieren der Zellstoffsuspension, wobei
• a) entweder unter Ausnutzung des maximal abführbaren Wärmestromes durch Behälter 7 auf der Kältemittelseite der Kühlplatten und
• b) wo erforderlich unter Gegenbeheizung der Kühlplatten bei Temperaturführung gemäß vorbestimmten Abkühlkurven die Wärmeabfuhr erfolgt;
• Lösen der Kühlplatten bei Erreichen der voreingestellten Mindesttemperatur;
• Öffnen der geräteseitigen Austrittsschleusenöffnung durch den Schieber 51;
• Transport des tiefgefrorenen Kunststoffbeutels 1 in die Austrittsschleuse 48;
• Schließen des Schiebers 51 und damit der Austrittsschleuse 48 gegenüber dem Zweikammermanipulator;
• Öffnen des Verschlusses 50;
• manuelle oder mechanische Entnahme des tiefgefrorenen Beutels 1;
• Schließen des Verschlusses 50;
• Trocknen der in der Austrittsschleuse 48 enthaltenen Luft zur Reduzierung der Luftfeuchte in der Schleuse auf Null.

This two-chamber manipulator carries out the following process steps:

• Opening the entrance lock 47, which can be triggered by pressing a button;
• Inserting the bag with the closure 49 open;
• Closing the shutter 49 by pressing a button, whereupon the program for the subsequent automatic steps is triggered;
• Drying the air contained in the entrance lock 47 through an air conditioning step to reduce the air humidity in the lock to zero;
• Opening the slide 52, ie access to the two-chamber manipulator;
• Transport of the plastic bag 1 from the entrance lock 47 into the two-chamber manipulator;
• Closing the slide 52 and thus the entrance lock 47;
• Alignment of the plastic bag 1 between the cooling plates of the two chambers;
• Pressing the cooling plates in about 0.5 seconds or faster to a preset contact pressure on the flat sides of the bag 14 and 15;
• Dissipation of heat from the bag to cool and freeze the pulp suspension, whereby
• a) either by utilizing the maximum dissipatable heat flow through container 7 on the refrigerant side of the cooling plates and
• b) where necessary, the heat is dissipated with counter-heating of the cooling plates with temperature control according to predetermined cooling curves;
• Loosen the cooling plates when the preset minimum temperature is reached;
• Opening the device-side outlet lock opening by the slide 51;
• Transport of the frozen plastic bag 1 into the exit lock 48;
• Closing the slide 51 and thus the outlet lock 48 with respect to the two-chamber manipulator;
• Opening the shutter 50;
• manual or mechanical removal of the frozen bag 1;
• Closing the shutter 50;
• Drying the air contained in the exit lock 48 to reduce the air humidity in the lock to zero.

Reference list

1

Plastic bag

2nd

Plastic film

3rd

Continuous conveyor

4, 5

chamber

6

Hollow body

7

Outer wall

7a

Interior wall

8th

Thermal insulation

9

inside

10, 11

Cooling plates

12, 13

Contact areas

14, 15

Flat sides

17th

Ribs

18th

Coating

19th

Partition

20th

Feed line

21

inner space

22

Return line

23

Top edge

24th

Level control

25th

Return line

26

Coolant plenum

27

Feed line

28

Hot gas ducts

29

contraption

30th

Piston rod

31

Working cylinder

32

gap

33

cooler

34

Return line

35

Coolant plenum

36

Feed line

37

inner space

38

Valve

39

Return line

40

Valve

41

Two-chamber manipulator

42

inner space

43

Two-chamber manipulator

44

casing

45

Feed line

46

Return line

47

Entrance lock

48

Exit gate

49

Closure

50

Closure

51

Slider

52

Slider

53

inner space

54

circulating funding body

55

Deflection device

56

Deflection device

57

Auxiliary device

58

Auxiliary device

Claims (29)

1. Method for freezing cell suspensions (1), in that the packaged cell suspensions between contact faces (12, 13) are brought to the temperature of a refrigerant and that the suspensions are deep-frozen by the refrigerant absorbing the heat from the packaged suspensions, characterised in that a supercooled refrigerant is applied which absorbs the heat of the packaged suspensions (1) in a not yet boiling condition, and that the method is conducted in such a way that the refrigerant bubbles produced at the onset of nucleate boiling are recondensed in the refrigerant substantially without net vapour formation.
2. Method according to Claim 1, characterised in that, while taking account of the heat capacity of the contact surfaces, the thickness of the packaged cell suspension between the contact surfaces is selected in such a way that a maximum cooling rate occurs.
3. Method according to Claim 1, characterised in that the thickness of the packaged cell suspension (1) between the contact surfaces (12, 13) is chosen for a given cooling rate.
4. Method according to any one of the preceding claims, characterised in that the heat transfer from the refrigerant to the contact surfaces is optimised by increasing the heat transfer surfaces on the refrigerant side.
5. Method according to any one of the preceding claims, characterised in that the refrigerant undergoes forced circulation in the liquid state in the circuit, a system for supercooling the refrigerant being provided whose cooling power is matched to the delivery capacity of the refrigerant circuit in such a way that, towards the end of the freezing process, the refrigerant does not reach its boiling temperature.
6. Method according to any one of the preceding claims, characterised in that, in order to increase their thermal conductivity, the contact surfaces (12, 13) are provided with minor surface roughness.
7. Method according to any one of the preceding claims, characterised in that on the contact-surfaces nucleation sites for initiating the nucleate boiling are made available with the aid of an increased surface area on the refrigerant side.
8. Method according to any one of the preceding claims, characterised in that the packages with the cell suspension which they contain are placed individually between the contact surfaces, brought to a uniform thickness by pressure and released after a predetermined minimum temperature has been reached, upon which the contact surfaces are released for a new freezing process.
9. Device for carrying out the method according to any one of the preceding claims with two cooling chambers (4, 5) through which a refrigerant flows, whose mutually facing outer sides serve as contact surfaces (12, 13) and delimit a gap (32), into which a packaged cell suspension (1) protrudes, characterised in that the device is provided with a two-chamber manipulator (29, 41, 43), whose chambers (4, 5) have essentially perpendicularly arranged cooling plates on their mutually facing outer sides, the mutually facing sides of which serve as contact surfaces (12, 13) and delimit a gap (32) into which a packaged cell suspension (1) suspended over the gap respectively protrudes, the cooling chambers (4, 5) interacting with a supercooler (33) for the refrigerant, which cools the refrigerant to below its boiling temperature.
10. Device according to Claim 9, characterised in that the cooling plates (10, 11) delimit the inner sides (9) of the chambers (4, 5), the refrigerant cooled to below its boiling temperature being fed through a feed line (27, 36) from the supercooler (33) to the chambers (4, 5) in immediate proximity to the cooling plates (10, 11) and passes over a sill (19) which extends as far as the upper edge of the contact surfaces (12, 13) of each cooling chamber (4, 5) and behind which the refrigerant passes down the counter-flow to a discharge line (25, 34) which leads to the inlet of the supercooler (33).
11. Device according to any one of the preceding claims, characterised in that the identically designed chambers (4, 5) have a line which discharges cold gases (29, 39, 40) and an additional feed line (37) through which refrigerant for replacing evaporation losses can be introduced.
12. Device according to any one of the preceding claims, characterised in that, on their chamber inner side (9) past which the liquid refrigerant flows, the cooling plates have an increased degree of thermal emission due to metal fins (16) and/or a coating of microporous material (18) which at least partially covers the cooling plate surfaces (9) past which the refrigerant flows, or due to anodic oxidation, or have black coloration.
13. Device according to any one of the preceding claims, characterised in that the contact surfaces (12, 13) of the cooling plates (10, 11) are provided with a smooth corrosion-protected coating with high thermal conductivity.
14. Device according to any one of the preceding claims, characterised in that the two-chamber manipulator (29) is designed as a jaw press for flexibly packaged cell suspensions (9), the gap (32) between, whose jaws when closed is adjusted to a uniform thickness of the packaged cell suspension.
15. Device according to any one of the preceding claims, characterised in that the contact surfaces (12, 13) are flat or matched to the shape of cell material suspension by surfaces the filled packages (9) spherical curvatures.
16. Device according to any one of the preceding claims, characterised in that the contact can be heated in order to control the surfaces (12, 13) cooling rate.
17. Device according to any one of the preceding claims, characterised in that channels (28) through which hat gas flows, are provided in the cooling plates (10, 11) in order to provide the cooling rate.
18. Device according to any one of the preceding claims, characterised in that the cooling plates (10, 11) are provided with an electrical heating system.
19. Device according to any one of the preceding claims, characterised in that the two-chamber-manipulator (29) is contained in a thermally insulated housing (44) which, for introducing and withdrawing of the packaged cell material suspensions, has locks (47, 48) which are to be opened and closed alternately.
20. Device according to any one of the preceding claims, characterised in that a continuous conveyor (3) is provided for introduction and extraction.
21. Device according to any one of the preceding claims, characterised in that each of the lock chambers (47, 48) is provided with a device for reducing air humidity, which is synchronised with the opening and closing of the locks.
22. Device according to any one of the preceding claims, characterised in that the supply of mementum to the chambers (4, 5) of the two-chamber-manipulator (29, 41, 43) between successive freezing processes achieves an unloaded excursion in which the contact surfaces (12, 13) are brought together until they touch one another.
23. Device according to any one of the preceding claims, characterised in that the contact surfaces (12, 13) can be heated automatically to room temperature between successive freezing processes.
24. Device according to any one of the preceding claims, characterised in that a heating plate which can be brought between the contact surfaces (12, 13) is used for compensatory heating.
25. Device according to any one of the preceding claims, characterised in that the manipulator (29, 41, 43) has a stationary chamber (4) and a moveable chamber (5) used to open and close the gap (32) between the contact surfaces.
26. Device according to any one of the preceding claims, characterised in that the refrigerant circuit leads through parallel line branches (20, 36) from a common feed line (45) into the internal spaces (37) of the chambers (4, 5) and, via a pump M, through line branches (25, 34) into a line (46) leading to the supercooler (33).
27. Device according to any one of the preceding claims, characterised in that the supercooled refrigerant is fed from its chamber (4) directly into the other chamber (5), and the refrigerant evaporation losses can be discharged from the chambers (4, 5) through two lines (29, 39).
28. Device according to any one of the preceding claims, characterised in that it has a programmed control system.
29. Device according to any one of the preceding claims, characterised by the following steps in the programmed control during the freezing of cell material suspensions packaged in flexible plastic sheets (2):

    1. Opening the inlet lock (47) by external button depression;

    2. Manually fastening the bag (1) to the continuous conveyor (3);

    3. Closing the seal (49) of the inlet lock (47) by button depression and starting the deep-freezing programme for the steps which subsequently take place automatically;

    4. Drying the inlet lock (47) using air conditioning to reduce the air humidity in the inlet lock to zero;

    5. Opening the slider (52) leading to the two-chamber-manipulator (43);

    6. Transporting the bag out of the inlet lock (47);

    7. Closing the slider lock (52);

    8. Aligning the bag (1) between the cooling plates (10, 11);

    9. Exerting the pre-set application pressure on the cooling plates;

    10. Withdrawing heat from the item to be frozen (cooling and freezing the cell material suspension)

    a) by utilising the maximum achievable heat flow through the container (7) on the refrigerant side of the cooling plates (10, 11);

    b) when necessary, with compensatory heating of the cooling plates for temperature control according to predetermined cooling curves;

    11. Releasing the cooling plates (10, 11) when the pre-set minimum temperature is reached;

    12. Opening the slider leading to the outlet lock (48);

    13. Transporting the bag (1) into the outlet lock (48);

    14. Closing the slider (51) of the outlet lock (48);

    15. Opening the seal (50) of the outlet lock (48),

    16. Manually or mechanically withdrawing the bag (1) from the outlet lock (48);

    17. Closing the seal (50) of the outlet lock (48);

    18. Drying the outlet lock (48) by air-conditioned reduction of the air humidity in the outlet lock to zero.

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