Device for freezing biological materials and use thereof

Abstract

The present invention relates to a device for freezing biological materials comprising an automated system for vertical lowering and raising, in order to control the cooling and / or freezing temperature gradient, and pertains to the field of human and / or animal assisted reproduction in cryopreservation techniques.

Description

[0001] DEVICE FOR FREEZING BIOLOGICAL MATERIALS AND ITS USE FIELD OF THE INVENTION

[0001] The present invention is situated in the fields of Biology, Zoology, Medicine, Biotechnology, Genetics and Engineering and relates to a device for freezing biological materials that features an automated vertical lowering and raising system for controlling the cooling and / or freezing temperature gradient used in the field of assisted human and / or animal reproduction in the cryopreservation technique. BACKGROUND AND ANTECEDENTS OF THE INVENTION

[0002] Cryopreservation is a process used to stabilize biological materials at very low temperatures. Previous attempts to freeze biological materials, such as live cells, often result in a significant loss of cell viability and, in some cases, up to 80% or more loss of this activity and cell viability.

[0003] Cellular damage during the cryopreservation process generally occurs as a result of intracellular ice formation within the living cell during the freezing phase or during subsequent recrystallization. Rapid cooling usually leads to the formation of more intracellular ice, since water molecules have not completely migrated out of the cell during the short time period associated with rapid cooling rates. Intercellular ice formation can also arise during recrystallization that occurs during warming or thawing cycles. If too much water remains inside the living cell, damage can occur due to the initial formation of ice crystals during the rapid cooling phase and subsequent recrystallization during the warming phases, and such damage is usually lethal.

[0004] On the other hand, slow cooling profiles during cryopreservation often result in an increase in solute effects where excess water migrates out of the cells. The excess water migrating out of the cells negatively affects the cells due to an increase in osmotic imbalance. Thus, cell damage occurs as a result of osmotic imbalances that can be detrimental to cell survival and ultimately lead to cell damage and loss of cell viability.

[0005] The freezing of biological materials, especially semen or embryos, is an important application in the field of assisted reproduction and in vitro fertilization (IVF). This technique allows for the preservation of biological material for a long period of time. Human semen, for example, can be stored under cryopreserved conditions for future use in artificial insemination or in vitro fertilization procedures. In the case of animal semen, the cryopreservation procedure enables the dissemination of genes and genetic improvement through the collection of high-producing semen.

[0006] After a successful in vitro fertilization (IVF) procedure, that is, the fertilization of eggs with sperm, the resulting embryos are cultured for a few days until they reach a suitable stage; at this point, any surplus embryos can be cryopreserved for future use.

[0007] Controlled cooling and freezing procedures are commonly used to prepare biological material for cryopreservation. This process involves gradually reducing the temperature of the biological material before freezing it, which helps minimize thermal shock and increase cell survival during the freezing process. Such a procedure is considered critical to ensuring the quality of the cryopreserved material.

[0008] This controlled cooling and freezing process helps protect cells from damage caused by ice crystal formation, allowing them to maintain their viability during the freezing procedure. It is an essential technique for successful cryopreservation.

[0009] Illustrating a traditional bovine semen freezing process, after semen is collected from a healthy, high-genetic-value breeding male, the semen is processed to remove seminal plasma and other impurities, leaving only high-quality spermatozoa. Subsequently, cryoprotective diluents are added to help protect the spermatozoa during the process (cooling and freezing ramps). This material is then packaged in a plastic straw and sealed. After cooling to a temperature below the animal's body temperature, typically between 4°C and 5°C, the material is left to stabilize for about 120 minutes. Then, these straws containing semen are placed in a container with liquid nitrogen where they are suspended at a height of 4 to 6 cm above the liquid nitrogen level.Under these conditions, the material will gradually lose its temperature in a freezing curve, and after the time specified in the protocol, the straws are immersed directly in liquid nitrogen at an approximate temperature of -196°C.

[0010] In the embryo freezing process, after a 7-day culture period, the embryos are sorted and placed in a straw with cryoprotectant medium and taken to the freezing device for cooling. Specifically, in this case of embryo freezing, there are protocols in which the straw is placed in the equipment at room temperature and then cooled to -6°C. In other protocols, the straw is placed directly in the equipment at -6°C where it stabilizes for 10 minutes, and from there, crystallization (seeding) is performed, a procedure that consists of immersing a piece of cotton in liquid nitrogen and touching it to the walls of the straws.After crystallization is performed, the straw is subjected to a freezing ramp, which will be from -6°C to -32°C with a drop of 0.5°C / minute. Upon reaching the target, the material remains for another 5 to 10 minutes to stabilize, and then the straws are dropped directly into liquid nitrogen at -196°C, as can be seen in the scientific publication.

[0011] The specific times in a cooling-freezing curve can vary depending on the type of biological material to be frozen, the protocols, and the laboratory's needs; however, generally the freezing curve is designed to allow for gradual freezing and minimize thermal stress.

[0012] In the conventional freezing method, the freezing ramp is achieved using an expanded polystyrene (EPS) thermal box with a metal rack where the straws containing biological material are placed at a fixed height of 4 to 6 cm from the nitrogen level, which is already cooled to between 5°C and 6°C. They are exposed to the chilled vapor for a period of 15 to 20 minutes, and then immersed in liquid nitrogen. This procedure does not allow for monitoring the freezing ramp, as there is no electronic control or temperature sensors to visualize the temperature drop of the straws. Manual action is required to remove the straws from the rack and place them in the liquid nitrogen.

[0013] Also known in the state of the art is equipment designed to meet the demand for freezing large volumes of biological straws, comprising a chamber in which the biological materials are accommodated for the execution of the cooling and freezing cycle. Temperature sensors that monitor the progressive reduction gradually according to a programmed curve are coupled to said chamber of the equipment. In this case, upon reaching the desired target temperature, the straws are manually removed from the chamber and immersed in liquid nitrogen. It is important to note that this type of equipment also involves a step of manually removing the straws from the chamber for subsequent immersion in liquid nitrogen.

[0014] Furthermore, one aspect to be considered in state-of-the-art devices and equipment is nitrogen consumption, since the injected nitrogen vapor is generated from a cryogenic hose directly immersed in liquid nitrogen with an electrical resistance to heat and generate vapor, resulting in a consumption considered high compared to the conventional procedure with a rack and expanded polystyrene (EPS) box.

[0015] Another drawback of this liquid nitrogen vapor injection equipment is the size of the cryogenic hose, which, due to the need for thermal insulation, must be quite thick and not very flexible.

[0016] Specifically for embryo freezing, there are also some types of equipment consisting of a perforated aluminum block with cavities for placing straws, temperature sensors housed in the block, and an electrical resistance around it that maintains a controlled temperature when immersing this block in liquid nitrogen. Particularly in this case, despite achieving good electronic temperature control, this type of product also has a high consumption of liquid nitrogen, since it is necessary to add an electrically heated block inside the liquid nitrogen and, due to its construction, the number of straws for this type of equipment is limited.

[0017] According to Vladimirov et al., (K. Vladimirov I, Tacheva D and Dobrinov V (2019) The Present and Future of Embryo Cryopreservation. Embryology – Theory and Practice. IntechOpen. Available at: http: / / dx.doi.org / 10.5772 / intechopen.80587) freezing and thawing can activate endogenous survival and repair mechanisms in pre-implantation embryos. Protocols based on the slow freezing method include an equilibration step, during which cells or tissues are placed in an aqueous solution containing PM CPAs at low concentrations (1.0 – 1.5 M) and sucrose (0.1 M) before being placed in ampoules or straws. After exposure to cryoprotective agents (CPAs), initial cell dehydration is observed followed by a return to isotonic volume with permeation of CPA and water.After loading the sample onto the straw / ampoule, the temperature is slowly cooled using a rate-controlled freezing device that allows samples to be cooled at different rates. Finally, the frozen objects are placed in liquid nitrogen for storage. Slow cooling is performed to ensure that cells / tissues are dehydrated before intracellular ice formation occurs. However, the ideal cooling rate varies greatly between cell and tissue types. A crucial step during the slow freezing protocol is the so-called ice crystal seeding, which can be performed manually or automatically, and occurs after the ampoules / straws pre-loaded with embryos are cooled below the freezing point of the solution, which is around -5 to -7°C.At these temperatures, the solutions remain thawed due to supercooling (reducing the temperature of a solution below its freezing point without the formation of extracellular ice). Supercooling leads to inadequate cell dehydration, and to avoid this, manual ice nucleation is most commonly performed by touching the ampoules / straws with a cold object pre-cooled with liquid nitrogen, such as tweezers, which leads to the formation of ice crystals. In this way, the remaining water in the cells is expelled due to the osmotic imbalance caused by the formation of ice crystals. After seeding the ice crystals, the slow freezing process continues at various cooling rates. When the temperature reaches values ​​ranging from -30 to -80°C, depending on the protocol, the ampoules / straws are immersed in liquid nitrogen.The article also concludes that despite the acceptable results achieved by slow freezing, it also has its negative effects; for example, it is time-consuming, as freezing an embryo usually takes between 2 and 3 hours depending on the cooling rate. Furthermore, it requires expensive freezers with rate control.

[0018] US Patent Application 2013111931 (A1) relates to a cryopreservation process and, more particularly, to a method and system for providing controlled-rate freezing and nucleation control of biological materials to minimize cellular damage resulting from intercellular ice formation and solute effects arising during the cryopreservation process. The disclosed system and method provide the ability to rapidly cool biological materials contained in flasks or other containers within a cooling unit, primarily through forced convective cooling, simultaneously using a uniform cryogenic flow in the vicinity of each of the plurality of flasks arranged within the cooling unit.Furthermore, the present system and methods are capable of providing rapid cooling of biological materials over a wide range of cooling rates, while simultaneously maintaining the temperature of the biological materials at the prescribed and specified temperature. More specifically, rapid cooling of biological materials is achieved by precisely controlling and adjusting the temperature of the cryogen being introduced into the system as a function of time. In a particular mode, the system embodiments are adapted to provide a gradual (rapid) drop in cryogenic temperature 102 to generate a higher degree of subcooling within the sample materials 100, thus minimizing the exothermic effects of phase transition (e.g., water-to-ice transformation) in the vials.Alternatively, the controlled-rate freezing or cryogenic cooling system and method are adapted to provide a gradual reduction in the temperature of the cryogenic cold gas at a rate of approximately -4.5°C per minute 112 and approximately -5.0°C per minute, in order to provide rapid cooling of the biological sample materials 110, 120 and still minimize any temperature variation from vial to vial.

[0019] US patent 4,799,358 refers to an apparatus for cooling and ultra-freezing samples of biological material, through which the disadvantages of known devices can be avoided. According to the invention, the samples are placed within a cooling zone that is enclosed between two plate-shaped cooling elements. The cooling elements consist of a layered arrangement of at least two layers of Peltier elements superimposed on each other alternately with thermoconductive metal plates, in such a way that the metal plates form intermediate layers between the layers of Peltier elements and enclose the entire structure on both sides.

[0020] US Patent Application 2023303959 (A1) provides an automated apparatus and method specifically designed for use in in vitro fertilization (IVF). In some embodiments, the method and apparatus comprise an imager with environmental controls and modifications that provides a safe environment for cells, eggs, sperm, and / or embryos as an incubator. The invention describes an integrated imager and incubator and a robotic transport with the environmental controls and modifications. In other embodiments, the application describes an imager, an incubator, a manipulator, and a robotic transport integrated with the environmental controls and modifications. A cell culture incubator includes a cabinet or housing having at least one chamber inside. Furthermore, within at least one chamber there are at least two stations for cell operations.Operations include, for example, storage, cell manipulation, cell selection, imaging, pipetting fluids into and out of the cell medium, scraping, mixing, etc. One station, for example, might be a holding area for cell culture plates. Another station might be an imaging station where an imager is provided to obtain images of cells in the wells of a plate. An additional station is a pipetting station where liquid is removed from or inserted into the wells of a plate. Yet another station is a manipulation station where cell manipulation in the wells of a plate is performed, for example, scraping. To allow plates to be actuated at each station, robotic transport is provided to move the plates between stations. In some embodiments, the transport is robotic and can be rotated to move cell media, such as a plate, between locations or stations.Robotic transport may have two or more wheels, such as a four-wheeled version. In some embodiments, the P-plate is based on the robotic transport and is moved between the storage station, the manipulation station, the imaging station, and other stations that may be provided within the system. The wheels 511 may be wheels that allow movement in the x and y directions to orient the plate to the position at a location. The body 512 of the transport includes in some embodiments the circuitry necessary to guide the transport. In some embodiments, visible field illumination creates images of sperm, eggs, and / or embryos in a vertical image stack. In other embodiments, information about sperm, eggs, and / or embryos may be obtained by image processing to reveal to scientists the most viable eggs for in vitro fertilization, the best sperm candidates for in vitro fertilization, and the health and viability of an embryo.The images provide documentation for the selection of candidate sperm and / or eggs. In some modalities, a stack of images is reproduced repeatedly, and in some modalities, at regular time intervals. Image processing of the captured images reveals the motility or mobility of the embryos, and such motility or mobility can be indicative of the health and / or viability of the embryo.

[0021] In order to overcome all the disadvantages of using prior art devices and methods and to improve efficient temperature control in cryopreservation procedures, the Applicant has developed a device for freezing biological materials that features an automated vertical lowering and raising system, and also includes a platform equipped with one or more temperature sensors for controlling the cooling and / or freezing temperature gradient. DESCRIPTION OF THE FIGURES

[0022] Figure 1 illustrates an exploded perspective view of the biological material freezing device of the present invention superimposed on an expanded polystyrene (EPS) box.

[0023] Figure 2 illustrates a perspective view of the device for freezing biological materials of the present invention.

[0024] Figure 3 illustrates a side view in cross-section of the device for freezing biological materials of the present invention, demonstrating an automated pantographic system for vertical lowering and raising.

[0025] Figure 4 illustrates a side view in cross-section of the device for freezing biological materials of the present invention, showing an automated threaded rod spindle system for vertical lowering and raising.

[0026] Figure 5 illustrates a side view in cross-section of the device for freezing biological materials of the present invention, showing a system with an automated rack for vertical lowering and raising.

[0027] Figure 6 illustrates a side view in cross-section of the device for freezing biological materials of the present invention, illustrating a system with an automated cable and pulley for vertical lowering and raising. DESCRIPTION OF THE INVENTION

[0028] The present invention relates to a device for freezing biological materials that features an automated vertical lowering and raising system for controlling the cooling and / or freezing temperature gradient, used in the field of assisted human and / or animal reproduction in the cryopreservation technique.

[0029] In a first embodiment, the automated vertical lowering and raising system comprises a pantograph system, a threaded rod spindle, a rack and pinion system, and / or a cable and pulley system that allows the liquid nitrogen level to be moved closer to and / or further away from the surface.

[0030] Furthermore, the automated vertical lowering and raising system of the invention features millimeter-precise control of movements throughout the lowering and raising range from 0 to 100 cm, preferably between 0 and 30 cm. Preferably and programmably, the automated vertical lowering and raising system of the invention has a movement range of 15 cm before immersion, considering a container filled with a liquid nitrogen level of 13 cm, and a total movement range of 27 cm.

[0031] Additionally, the invention's automated vertical lowering and raising system provides temperature control directly proportional to the millimeter-precise control of the lowering and raising stroke. This assumes that the temperature at the "0 movement" position is close to ambient temperature, approximately 20°C, and that at the "15 cm movement" position it is closer to -150°C. These parameters vary according to the container size, nitrogen level, and ambient temperature.

[0032] In particular, the pantographic, threaded rod spindle, rack and pinion, and / or cable and pulley systems of the present invention provide a suitable cooling and freezing environment to accommodate horizontal straws containing biological material. Furthermore, the pantographic, threaded rod spindle, rack and pinion, and / or cable and pulley systems of the present invention ensure precise temperature control with a maximum variation of 0.5°C during the cooling and freezing ramp, providing controlled conditions for the execution of cooling and freezing protocols according to programmed ramps, thus resulting in better conditions for the preservation of biological materials.

[0033] The cooling rate of biological material depends on several factors, including the size of the container, the amount of liquid nitrogen in the container, the shape of the container, and environmental conditions, which makes it difficult to measure a fixed and exact temperature value based on the distance from the liquid nitrogen level. The automated vertical lowering and raising system of the present invention provides the programmed temperature precision in each movement of the cooling and freezing curve step of said device for freezing biological materials.

[0034] The invention's automated vertical lowering and raising system also provides electronic temperature sensors that continuously monitor the temperature in the region where the platform containing the biological material is located. Depending on the platform's capacity, a range of temperature sensors can be distributed, properly spaced to monitor the entire internal area of ​​the container.

[0035] In a second embodiment, the present invention relates to the use of a device for freezing biological materials with an automated vertical lowering and raising system for controlling the cooling and / or freezing temperature gradient used in the field of human and / or animal assisted reproduction in the cryopreservation technique process.

[0036] The present invention represents a substantial improvement over conventional cooling and freezing methods, since the device of the present invention allows for meticulous monitoring and control of the ramp temperature. Compared to prior art equipment that already performs this control electronically, the clear advantage lies in the meticulous control and optimization of liquid nitrogen consumption, since with the process of level approximation in the automated vertical lowering and raising system of the invention, it is not necessary to use any body heated directly to liquid nitrogen. DETAILED DESCRIPTION OF THE INVENTION

[0037] According to figure 3, by way of example, the device for freezing biological materials comprising an automated pantographic system for vertical lowering and raising of the present invention comprises a rectangular structure (1) with an opening (2) in its upper face (3) allowing access to the tray (4) which rests on the platform (5) moved by the rods (6) of the pantographic mechanism which is connected to a guide (7) that is moved by a spindle (8) coupled to a motor (9), connected to a printed circuit board (10) with dedicated microcontrollers, which in addition to actuating the motor (9) for the movement of the pantographic system, continuously monitors the temperature sensor (11) fixed at the lower end of the platform (5).Additionally, through a touch display (12), seen in figure 2, installed on the front face (13), seen in figure 1, it is possible to adjust, through screens with programmed icons, the type of cooling and freezing ramp, as well as monitor the process by viewing the temperature in real time.

[0038] Furthermore, as can be seen in Figure 1, the rectangular structure (1) is superimposed on an expanded polystyrene (EPS) box (14), which can also be replaced by any type of vacuum-insulated or expanded polyurethane (PU) container, in which liquid nitrogen will be placed at an indicated level, according to the protocol to be executed, a lid (15) seals the device to block temperature exchange with the environment. EXAMPLE TESTS 1 – PANTOGRAPH SYSTEM

[0039] The operation of the device for freezing biological materials with an automated vertical lowering and raising system occurs through the addition of liquid nitrogen to the expanded polystyrene (EPS) box (14) up to the level stipulated in the protocol, then the straws (16) with biological material are placed on the tray (4) supporting it on the platform (5) and closing the lid (15) on the rectangular structure (1). When the cooling or freezing curve is initiated via the touch display (12), the platform (5) will move, by the rods (6) of the pantographic mechanism, towards the level of the liquid nitrogen, seeking the position where the temperature corresponds to the previously programmed one. Specifically, in semen freezing, the system will execute the cooling ramp to 5°C or 6°C, followed by stabilization for 120 minutes before initiating the freezing ramp.

[0040] In embryo freezing, it is permitted to have the cooling curve down to -6°C, where the 10-minute period for stabilization and indication of the moment of crystallization (seeding) begins, for this, the lid (15) is removed to have access to the straws (16), and subsequently the freezing ramp from -6°C to -32°C is started.

[0041] In both situations above, after completing the freezing ramp, the platform (5) descends until it is immersed with the blades (16) in the liquid nitrogen. EXAMPLE 2 – THREADED ROD SPINDLE SYSTEM

[0042] The operation of the device for freezing biological materials with an automated vertical lowering and raising system occurs through the movement of the platform (5) via a threaded rod spindle (18), where access to the tray (4) which rests on the platform (5) is moved by the nut (17) driven by the threaded rod spindle (18) coupled to a motor (9), connected to a printed circuit board (10) with dedicated microcontrollers, which, in addition to driving the motor (9) to move the threaded rod spindle (18), continuously monitors the temperature sensor (11) fixed to the lower end of the platform (5). EXAMPLE 3 – RACK SYSTEM

[0043] The operation of the device for freezing biological materials with an automated vertical lowering and raising system occurs through the movement of the platform (5) via the rack and pinion system (19), where access to the tray (4) which rests on the platform (5) is moved by the rack and pinion (19) driven by the gear (20) coupled to a motor (9), connected to a printed circuit board (10) with dedicated microcontrollers, which, in addition to driving the motor (9) to move the gear (20) and rack and pinion (19), continuously monitors the temperature sensor (11) fixed to the lower end of the platform (5). EXAMPLE 4 – SYSTEM WITH CABLE AND PULLEY

[0044] The operation of the device for freezing biological materials with an automated vertical lowering and raising system occurs through the movement of the platform (5) by cable (21) and pulley (22), where access to the tray (4) which rests on the platform (5) is moved by the cable (21) which is wound by the pulley (22) coupled to a motor (9), connected to a printed circuit board (10) with dedicated microcontrollers, which, in addition to actuating the motor (9) to retract or release the cable (21), continuously monitors the temperature sensor (11) fixed to the lower end of the platform (5). RESULTS

[0045] Liquid nitrogen has a temperature of approximately -196°C, and when a material is placed at a certain distance from the surface of the liquid nitrogen, the ambient temperature around that material decreases due to heat transfer from the environment to the container.

[0046] In the device for freezing biological materials with an automated vertical lowering and raising system of the present invention, the paddles are placed on the automated lifting platform and, upon starting the ramp, the temperature sensor reads the region in which it is positioned, moving slowly until the programmed temperature of the sensor coincides with the temperature stipulated in the cooling ramp, and thus continuing with the movement and reading cycles until the target temperature is reached.

[0047] An improved aspect of the device for freezing biological materials with an automated vertical lowering and raising system of the present invention is the ability to trigger a new phase of ramp movement, which includes immersing the platform, along with the paddles, in liquid nitrogen, avoiding a manual step in the procedure, adding an advantageous operational gain and preventing the paddles from coming into contact with ambient temperature during the transition, thus avoiding temperature exchange for this short period.

[0048] Additionally, using the device for freezing biological materials with an automated vertical lowering and raising system of the present invention provides a saving of more than 30% of liquid nitrogen, in a given cooling and freezing curve protocol, compared to a nitrogen vapor injection device, which is similar to the conventional procedure, with the advantage of monitoring and controlling the ramp temperature, essential in studies and analyses of freezing techniques, as well as providing the possibility of freezing both semen and embryos.

[0049] Furthermore, the present patent application offers a substantial advantage in terms of compact construction, making it particularly suitable for use on workbenches. Its design is adaptable to the standard dimensions of widely used expanded polystyrene (EPS) boxes, which retain liquid nitrogen for an extended period of time.

[0050] The platform lifting system can be implemented using pantograph systems, a threaded rod (spindle), a rack and pinion system, or cables and pulleys connected to electronically controlled stepper motors, making them a versatile and efficient solution for laboratory applications.

[0051] The minimalist design also offers an advantage in terms of material savings during construction, making it a more affordable piece of equipment than other existing models with freezing ramp control and monitoring. Its compact size and light weight also facilitate its use on laboratory benches.

Claims

1 / 3 CLAIMS 1. DEVICE FOR FREEZING MATERIALS, characterized by comprising an automated vertical lowering and raising system; wherein said automated lowering and raising system comprises a pantographic, threaded rod spindle, rack and pinion and / or cable and pulley system; and wherein said automated lowering and raising system further comprises electronic temperature sensors (11).

2. DEVICE, according to claim 1, characterized by the pantographic system comprising a rectangular structure (1) with an opening (2) in its upper face (3) allowing access to the tray (4) which rests on the platform (5) moved by the rods (6) of the pantographic mechanism connected to a guide (7) moved by a spindle (8) coupled to a motor (9) and connected to a printed circuit board (10) with dedicated microcontrollers, which drives the motor (9) and monitors the temperature sensor (11) fixed at the lower end of the platform (5).

3. DEVICE, according to claim 1, characterized by the threaded rod spindle system comprising a rectangular structure (1) with an opening (2) in its upper face (3) allowing access to the tray (4) which rests on the platform (5) through the threaded rod spindle (18) moved by the nut (17) coupled to a motor (9) and connected to a printed circuit board (10) with dedicated microcontrollers, which drives the motor (9) and monitors the temperature sensor (11) fixed to the lower end of the platform (5).

4. DEVICE, according to claim 1,. 2 / 3 characterized by the rack and pinion system comprising a rectangular structure (1) with an opening (2) on its upper face (3) allowing access to the tray (4) which rests on the platform (5) through the rack and pinion system (19) driven by the gear (20) coupled to a motor (9) and connected to a printed circuit board (10) with dedicated microcontrollers, which drives the motor (9) and monitors the temperature sensor (11) fixed at the lower end of the platform (5). 5.DEVICE, according to claim 1, characterized by the cable and pulley system comprising a rectangular structure (1) with an opening (2) in its upper face (3) allowing access to the tray (4) which rests on the platform (5) by cable (21) and pulley (22) moved by the cable (21) which is wound by the pulley (22) coupled to a motor (9) and connected to a printed circuit board (10) with dedicated microcontrollers, which drives the motor (9) and monitors the temperature sensor (11) fixed at the lower end of the platform (5).

6. DEVICE, according to claim 1, characterized by the automated vertical lowering and raising system comprising millimeter control of the movements along the lowering and raising stroke within a range of 0 to 100 cm. 7.DEVICE, according to any one of claims 2 to 5, characterized in that said rectangular structure (1) comprises an expanded polystyrene (EPS) box (14), a container with vacuum insulation or expanded polyurethane (PU).

8. DEVICE, according to any one of. 3 / 3 claims 1 to 8, characterized by further comprising a touch display (12) installed on the front face (13).

9. DEVICE, according to any one of claims 1 to 8, characterized by further comprising horizontal blades (16).

10. USE OF THE DEVICE FOR FREEZING BIOLOGICAL MATERIALS, as defined in claims 1 to 9, characterized by comprising the control of the cooling and / or freezing temperature gradient used in the cryopreservation technique in the field of human and / or animal assisted reproduction.

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