ES2715518B2 - SYSTEM FOR CARRYING OUT CHEMICAL, BIOLOGICAL AND / OR MEDICAL PROCEDURES - Google Patents

Description

DESCRIPTION

SYSTEM TO CARRY OUT CHEMICAL, BIOLOGICAL AND / OR PROCEDURES

DOCTORS

1. Field of the invention

The present invention relates to a system for carrying out chemical, biological and / or medical procedures, preferably following respective protocols.

2. Technical background

In particular, for compact laboratory-level systems to carry out chemical, biological and / or medical procedures, such as analytical procedures or the like, it is often crucial to prevent contamination of substances contained in a container, such as for example a test tube, by aerosols or vaporized substances that come from test tubes located in the vicinity. In view of this, the objectives of the present invention are directed to provide a system that prevents such contamination of containers by aerosols, vaporized substances or the like. The objects of the invention, in particular, are aimed at providing a compact, completely closed system that can be applied as laboratory equipment.

The chemical, biological and / or medical procedures that follow the corresponding protocols are carried out using containers or containers such as test tubes, vials, plates, flasks, channels, surfaces or the like, whereby substances such as reagents or products of reaction are introduced and extracted therefrom, for example, using suitable pipettes. Currently, for example, procedures for analyzing genetic materials or proteins have gained interest.

In conventional systems such as the system disclosed in WO 2010/089138 A1, a plurality of containers are retained in corresponding retention elements in rows so that substances can be added or removed from the containers at the same time or one after the other. other.

During such procedures, it is common for the containers to remain open so that the reagents within the containers can be handled. However, it is important that the containers are separated from each other as the contents can be highly sensitive, dangerous, contaminating or volatile. On certain occasions, a corresponding protocol for the procedure in question may require various reagent transfers between containers, which can promote the generation of aerosols. Such aerosols can move undesirably into adjacent containers or packages and thus cause contamination of the containers.

The objectives of the present invention are aimed at providing a system that reduces or even completely prevents such contamination. Therefore, it is an object of the present invention to provide a system for carrying out chemical, biological and / or medical procedures that can reduce such contamination in an effective and efficient way, whereby the corresponding system components must be easy to control. and not complex. The system should preferably be a compact, completely enclosed system at the laboratory level.

This object is achieved by the content of the independent claims.

3. Summary of the invention

According to the invention, a system is provided for carrying out chemical, biological and / or medical procedures. Such procedures may include analysis of specific substances or other reactions that may follow protocols such as chemical, biological and / or medical protocols. As will be clear to the person skilled in the art, a chemical, biological and / or medical protocol is a sequence of steps carried out, for example, during an analysis procedure or a reaction procedure.

According to the invention, the system comprises a retention means for retaining a plurality of containers. The retaining means may comprise, for example, holes or different means for accommodating the containers or they may be formed integrally with the containers. Thus, the containers are suitable for containing substances relevant to the process in question such as reagents or reaction products. The procedures can therefore be carried out in those containers or packages. Thus, reagents and / or reaction products can be introduced or extracted from said vessels using, for example, pipettes during the procedure as required, for example, by the respective protocol. As will be clear to the skilled person, common reagents of interest can be, for example, samples, buffers, solutions or the like. Suitable containers can be test tubes, vials, plates, flasks, channels, surfaces, or the like.

Additionally according to the invention, the retaining means is configured and / or arranged to such that the containers are arranged in at least two essentially parallel rows along a first direction when held by the retention means. As the skilled person will understand, due for example to manufacturing tolerances, perfect parallelism may not be achieved such that the term essentially parallel is to be understood as parallel within customary construction tolerances.

The retaining means may comprise a frame structure suitable or the like for retaining the containers or into which containers can be inserted. Containers can similarly be formed integrally with such a frame structure. With such a frame structure, the containers are arranged in at least two (or more) rows along a first direction. Depending on the apparatus, said direction may be a direction of movement of the containers towards a position for interaction with a pipette. Alternatively, a plurality of pipettes corresponding to a plurality of containers within a row or all rows may be provided to allow simultaneous treatment of the containers. Furthermore, the retaining means may be a frame structure adapted to retain a plurality of containers such that the containers form a network (ie, the containers being arranged in essentially parallel rows and essentially parallel columns).

The system further comprises a gas outlet arranged to provide a flow of gas along the first direction. Preferably the gas is air. Alternatively, suitable gases include nitrogen, argon, and helium. A suitable gas outlet can be a single port, multiple ports, ie at least two ports, an array of ports, and a suitable nozzle. The outlet can have an essentially circular shape or an elongated shape as desired. In a preferred embodiment, the gas outlet comprises a matrix of orifices. Such a matrix is advantageous in that it can be adapted to the needs of the system and in particular it can be used to extend the gas flow to a desired height as described below. In a preferred embodiment, the gas outlet comprises a matrix of circular orifices, preferably with diameters between 1mm and 3mm, spaced between 1.5mm and 3.5mm measured center to center. Preferably, the gas outlet is adapted to provide a flow of gas, in a region between 1 cm and 10 cm in length by a length of between 1 cm and 15 cm. The gas outlet is preferably provided at a distance of between 1 cm and 5 cm before the openings of the containers. The gas outlet is arranged to provide gas flow along the container openings of at least one of the at least two rows of containers. Although it may be possible to selectively provide a flow of gas to a single row if desired, in a preferred embodiment, the gas outlet is arranged to provide the gas flow along the openings of the containers of a plurality of rows of containers. This can be achieved by providing the gas outlet comprising a matrix of orifices.

According to the invention, at least one flow barrier is arranged along the first direction and between the at least two rows of containers to separate the openings of one of the at least two rows of containers from the openings of the other of the at least two rows of containers. In other words, the flow barrier is adapted to prevent a flow or transfer of gas, aerosols, vaporized reagent or the like from one of the at least two rows of containers to the openings of the other of the at least two rows of containers.

In a preferred embodiment, the retention means is configured such that at least within each row, the openings of the containers are disposed within a common plane along the first direction when they are retained by the retention means, whereby the gas outlet is arranged to provide gas flow along at least all of the openings within a row. Thus, part of the containers or all of the containers can be retained by the retainer in such a way that the openings of the containers remain essentially in a common plane. Flow barriers are arranged between pairs of rows of containers that extend in parallel along the first direction and in a height direction perpendicular to the first direction and perpendicular to said common plane of the openings. Due to the arrangement of the at least one flow barrier between the at least two rows of containers, the at least two rows of containers are separated from each other. Thus, unwanted transfer, for example of aerosols or vaporized substances, is effectively prevented. Additionally, because the flow of gas, aerosols or the like generated within each row is provided it can be efficiently transported away from the respective reaction zones.

The present invention further provides a method of carrying out chemical, biological and / or medical procedures which comprises retaining a plurality of containers in at least two essentially parallel rows along a first direction.

According to the invention, the method further comprises providing a gas flow along the first direction and at least along the openings of the containers of one of the at least two rows of containers. The method further comprises separating the openings of one of the at least two rows of containers from the openings of the other of the at least two rows of containers using at least one flow barrier arranged along the first direction and between the at least two rows of containers. minus two rows of containers.

As the skilled person will understand, said method according to the invention can be combined with the preferred embodiments described in connection with the system according to the invention.

4. Description of preferred embodiments

In the following, the invention is described by way of example with reference to the accompanying figures in which:

Figure 1 shows a three-dimensional view of a system for carrying out chemical, biological and / or medical procedures;

Figure 2 shows a retaining means for retaining a plurality of containers;

Figure 3 is a three-dimensional illustration of the retention means retaining a plurality of containers, flow barriers, and a flow of gas along the container openings of a row of containers; and

Figure 4 shows an additional retaining means for retaining a plurality of containers.

Figure 1 shows an example of a system 100 performing chemical, biological, and / or medical procedures. System 100 comprises a main housing 101 that covers internal components such as a controller (microprocessor) that is configured to control operations of system components. As will be clear to the skilled person, system component operations can be implemented in the controller using suitable software.

The housing 101 of the system 101 encloses a partially open procedure space 103 within which the procedures discussed above are performed. In the figure, a pipette 105 is visible through an opening in a side wall of housing 101. The pipette is mounted on an arm 106 that is controlled by a controller (microprocessor) of the system. A door 107 is provided in a front wall of the housing 101 that an operator can open to insert containers into the system for additional procedures. To this end, within the space 103, a retaining means 200 (eg suitable frame structures, not visible in the figure) may be removably provided to house the containers. May A suitable algorithm can be provided to the controller such that using the arm 106, chemical, biological and / or medical procedures can be carried out automatically following a suitable protocol, for example implemented as software by the controller. Thus, in a preferred embodiment, the system comprises means 106, 105, preferably at least one pipette 105, for adding or removing a substance to or from at least one of the plurality of containers. Preferably, the system further comprises a controller configured to automatically control said means, preferably said pipette.

Figure 2 shows a frame 201 as an exemplary part of the retaining means 200. Introduced into the system 100, such a frame extends along the first direction 601 (see also Figure 3 below) and includes a plurality of cavities 203 or holes 203 of essentially circular shape, to house each cavity 203 a container 300 Alternatively, the containers 300 may be formed integrally with the frame 201. The containers 300 shown in Figure 2 (the frame 201 holds by way of example eight containers 300 of which only one is indicated by a reference number) are hence a plurality of containers that are arranged in a row along a first direction being retained by a part of the retaining means.

For example, using such a frame 201, in a preferred embodiment, the retention means 200 comprises at least two frames 201 extending along the first direction 601, the frames 201 being removably capable of being inserted into the housing. 101 of system 100, each frame 201 having a plurality of cavities 203 of essentially circular shape, each cavity 203 being for retaining a respective container 300 of the plurality of containers 300.

As shown in Figure 2, when inserted into the frame 201, the openings 301 of the containers 300 are arranged within a common plane along the first direction 601, so that in the example shown said common plane it is essentially a plane that also includes the cavities 203 of the frame 201. Thus, preferably, an opening 301 of a respective container 300 of the plurality of containers 300 is arranged at essentially the same height 603 (see Figure 3 below). that the cavity 301 is essentially circular in shape when the respective container 300 is retained by the corresponding frame.

The frame can be provided with a two-dimensional code, for example a QR code, to a suitable position such as for example on a top surface at the end left of frame 201 in figure 2. Therefore, in a preferred embodiment, frame 201 is provided with a two-dimensional code, preferably with a QR code (Quick Response, rapid response), to identify substances by container or procedures carried out. carried out in each container 300 held by the frame 201. Accordingly, the system 100 preferably comprises means for reading said two-dimensional code, when the frame 201 is entered into the system and the controller is configured to automatically carry out a procedure according to the information stored in the two-dimensional code. As further illustrated in Figure 2, the frame may retain one or more different containers or packages 313 that can be used to retain additional substances as desired.

Figure 3 schematically illustrates the retention means 200 that holds a plurality of containers 300. As shown, the retention means 200 is configured such that the plurality of containers 300 are arranged in at least two rows essentially parallel to it. along the first address 601 when held by the holding means 200. In the example shown, the first two rows parallel to the direction 601 visible in the figure are indicated by reference numerals 350 and 360. The retaining means 200 can be realized for example by multiple frames 201 (three in the example shown in the Figure 3) as shown in Figure 2. However, the retaining means 200 may also be realized as a retaining element to retain a network of containers 300 so that rows of containers are formed along the first direction 601 as illustrated.

As can be seen from Figure 3, the system further comprises a gas outlet (not shown) arranged to provide a flow of gas (illustrated by arrows forming groups 501, 503) along the first direction 601 and at least along the container openings of one of the at least two rows of containers. In the example shown, the gas flow occurs along the openings of the containers in row 350. The gas flow can be limited to a single row such as said row 350, but it can also be along more than one or all rows. As shown, two flow barriers 400, in the example shown wall-shaped elements 400, are arranged along the first direction 601 and between at least two rows of containers 300 to separate the openings 301 from one of the at least two rows of containers from the openings 301 of the other of the at least two rows of containers. In FIG. 3, a first flow barrier 400 is provided between row 350 and row 360 to prevent a transfer of gas, gaseous substances, aerosols and the like between the openings 301 of the containers 300 for example from row 350 to the openings 301 of the containers 300 of the row 360, and vice versa.

As further illustrated in Figure 3, in a preferred embodiment, the at least one flow barrier 400 extends along the first direction 601 from a first position 801 before the containers along the first direction 601 to a second position 803 behind the containers 300 along the first direction 601 so that it is positioned between all the containers 300 of the at least two rows 350, 360 of containers 300. As shown, each flow barrier it extends along the first direction and along a second direction 603, ie a height direction. In other words, preferably, the at least one flow barrier is essentially wall-shaped and the height of the at least one flow barrier is measured in a direction essentially perpendicular to said common plane. As illustrated, in a preferred embodiment, the at least one flow barrier 400 has an essentially uniform height along its length that is between 0.5 cm and 10 cm, preferably between 0.8 cm and 9 cm. , more preferably between 0.9 cm and 8 cm and most preferably between 1 cm and 7 cm.

Depending on the height, in a preferred embodiment, the length of the at least one flow barrier in the first direction is between 0.5 cm and 50 cm, preferably between 0.8 cm and 40 cm, more preferably between 1 cm and 30 cm, and most preferably between 1 cm and 20 cm.

In FIG. 3, two exemplary flow barriers 400 are provided for separating vessels or rows of vessels. The horizontal flow runs from a gas outlet (not shown) that is arranged at a distance in front of the barriers. It follows that the distance between the gas outlet and the flow barriers should not be too small, so that a completely non-turbulent and uniform developed gas flow is applied. In a preferred embodiment, the distance between the at least one flow barrier and the gas outlet is not less than 1 cm, preferably not less than 2 cm, more preferably not less than 3 cm, even more preferably not less than 4 cm , and most preferably not less than 5 cm. It follows that maintaining such a distance aids in desirable flow development by helping to prevent turbulence. Turbulence is undesirable as it can promote the exchange for example of aerosols over flow barriers.

In a preferred embodiment, the system comprises at least three, preferably a plurality of rows of containers and at least two, preferably a plurality of flow barriers respectively arranged between pairs of rows of containers, whereby the gas outlet is provided with such that the gas flow comprises a first part that flows through along at least all of the container openings within each row between the flow barriers and a second portion that flows above the flow barriers. As can be deduced from figure 3, part of the gas flow (a first part) is channeled through said barriers, that is, it flows between the two barriers, and a part (a second part) flows over or over the barriers faster. The speed difference is due to the fluid resistance produced by the aspect ratio (height / spacing) of the space between the barriers. As illustrated in the figure, at a certain length after the channels, the gas or air flow is drawn downwards or alternatively upwards, laterally, diagonally or in the direction of the flow.

To this end, in a preferred embodiment, the system 100 comprises at least two flow barriers 400 and a source 700 of negative pressure, preferably a pump 700, to create a pressure difference between the source 700 of negative pressure and the outlet of gas such that the gas provided by the gas outlet moves toward the negative pressure source 700. By providing the negative pressure source 700 it is possible to generate a directed gas flow (preferably air flow) from the gas outlet to the negative pressure source. This configuration turned out to be advantageous since by directing the gas flow in this way, turbulences that could otherwise promote unwanted exchange for example of aerosols between rows can be effectively prevented with a simple non-complex construction.

Preferably, the gas outlet is arranged to cause the gas flow to flow along an initial flow direction (for example along the first direction 601), whereby after having passed at least all openings the containers of a row 350, the gas flow is directed in a predetermined direction different from the initial direction, for example downwards as shown in figure 3.

In a preferred embodiment, system 100 further comprises a controller for controlling negative pressure source 700 such that the gas flow rate between the at least two flow barriers is between 100 and 200 cm3 / s, preferably between 120 and 180 cm3 / s, more preferably between 140 and 170 cm3 / s, and most preferably between 160 and 170 cm3 / s. These values for the gas flow rate are given per row of vessels 300. Thus, the system can be expanded, that is, it may comprise a greater number of rows of vessels, whereby these values are essentially constant per row, of essentially independent of the number of rows, that is, the size of the system. Preferably, in this embodiment, the flow velocity values are such that the velocity of the gas between the gas outlet and the at least one

one

flow barrier is between 0.3 m / s and 0.5 m / s. It follows that above this value, the flow was no longer laminar but began to be turbulent. In addition, the high velocities over the openings 301 of the tubes 300 can cause the pressure to drop locally, thus promoting evaporation. This can occur in high pressure systems such as air jets.

In a preferred embodiment, the negative pressure source is a pump configured to pump gas at a flow rate that is not less than that of the gas outlet per row of vessels.

Thus, in a preferred embodiment, a preferably low-pressure gas flow is conducted locally along a series of flow barriers, positioned parallel to the direction of the gas flow, ie along the first direction. The air flow is preferably extracted by a negative pressure source, which causes the flow to be directed (upwards, downwards, laterally, diagonally or along its initial). Unlike, for example, conventional air-only systems, this solution ensures that turbulence will not cause the accidental transport of aerosols or other elements (such as small particles) into containers in adjacent rows. Alternative solutions, such as high pressure jets, are more expensive and complex (for example a fine flow concentration is required) so high turbulence can cause uncontrolled spread of aerosols, particularly at the boundary between the jets or if it is found any type of barrier or obstacle. Similarly, high velocities above the vessels can cause a local pressure drop and promote evaporation. Furthermore, with such solutions extraction is only possible in the direction of the gas flow, with a high risk of jet contact, which can cause uncontrolled air currents within the device and deposits of potential contamination.

Unlike conventional solutions, according to the invention, the use of parallel flow barriers guarantees a desirable flow development and more predictable air conditions. In addition, the barriers prevent lateral transfer of aerosols. In a preferred embodiment, the width to height ratio of the barriers can be chosen such that the air flow is stronger over the barriers than along the barriers. In this way, two simultaneous phenomena can develop. On the one hand, the aforementioned localized unidirectional transport of aerosols in parallel to the barriers is possible. On the other hand, a higher gas velocity or air cap is developed above the barriers, which further prevents the transfer of aerosol through the barriers. It follows that this solution is ideal for handling containers with liquid handling devices, robots, pipettes or fluid handling tools that can be inserted and removed from the tubes.

Furthermore, since the gas flow velocity can also be kept low, it is possible to extract this gas or air in a short length behind the barriers with low turbulence and in any direction, by means of a negative pressure source. This source redirects the flow towards itself, prevents aerosol spread mechanisms, such as by contact, and minimizes circulation to avoid accumulating deposits of contamination.

In a preferred embodiment, the negative source and the gas outlet can be part of the same gas / air circulation system, which helps balance the positive and negative pressures required to direct the gas flow and to extract it. In another preferred embodiment, a filter (eg HEPA or other) is provided in the circulation system that continuously removes aerosols and helps to improve gas quality within the device.

Figure 4 shows a retention means 200 comprising a further embodiment of a frame 201 '. Introduced into system 100, such a frame extends along the first direction 601 (see also Figure 3 below) and is adapted to retain at least two rows, in the example shown three rows 350, 360, 370 of containers 300.

Flow barriers 400 are arranged between rows 350, 360, 370 of containers. The flow barriers are arranged to channel or guide a flow of gas (not shown) at least along the holes 203 to remove gaseous substances, aerosols, or the like. The flow barriers can be separate elements attached to frame 201 'or they can be an integrated part of a structure that also includes frame 201'. Similarly, the containers can be removably inserted into corresponding holes in frame 201 'but can also be formed integrally with frame 201'.

Figure 4 further shows containers 313, with an additional container 313 being arranged per row 350, 360, 370 of containers. Such additional containers 313 may be used to contain a different reagent than the containers 300. As shown, additional flow barriers 401 are provided between the additional containers 313 that serve the same purpose as the flow barriers 400 that are disposed between them. rows 350, 360, 370 of containers 300.

Examples

In a particularly preferred embodiment, the system can be characterized by:

- The gas outlet is located 3 cm in front of the flow barriers 400, with an outlet air velocity of 0.5 m / s and a flow velocity of 165 cm3 / s per space between barriers.

- The height of the barriers 400 is 3 cm above the plane formed by the openings 301 of the containers 300 and the separation between the barriers 400 is 1 cm. The containers 300 are located in rows in the gap between the barriers 400. The length of the barriers 400 is 12 cm.

- The negative pressure source has a cross section of 6 cm x 12 cm, starting 1 cm after the length of the 803 barriers. The outlet air velocity is 0.5 m / s and the flow velocity is 165 cm3 / s per space between barriers 400.

one

Claims (1)

System (100) to perform chemical, biological and / or medical procedures that includes a retention means (200) to retain a plurality of containers (300), whereby the retention means (200) is configured such that the containers (300) are arranged in at least two rows (350, 360, 370) essentially parallel along a first direction (601) when retained by retaining means (200), characterized because The system (100) further comprises a gas outlet arranged to provide a flow (501, 503) of gas along the first direction (601) and along openings of the containers (300) of at least one of the at least two rows (350, 360) of containers (300), at least one flow barrier (400) being arranged along the first direction (601) and between the at least two rows (350, 360) of containers (300) in a height direction perpendicular to the first direction and perpendicular to said common plane of the openings, to prevent a transfer of gas, gaseous substances, aerosols and the like between the openings (301) of the containers of the rows (350, 360), and characterized in that the gas outlet is arranged such that the gas flow comprises a first part that flows along at least all the openings of the containers (300) within each row between the flow barriers (400) and a second part that flows over the flow barriers (400). System (100) according to claim 1, characterized in that the retaining means (200) is configured in such a way that at least within each row, the openings of the containers (300) are arranged within a common plane along the first direction (601) when retained by the retaining means (200), whereby the gas outlet is arranged to provide the flow (501, 503) of gas along at least all the openings within a row. System (100) according to claim 1 or 2, characterized in that the at least one flow barrier (400) extends along the first direction (601) from a first position (801) before the containers (300 ) along the first direction (601) to a second position (803) behind the containers (300) along the first direction (601) so that it is positioned between all the containers (300) of the at minus two rows (350, 360) of containers (300). System (100) according to any one of the preceding claims, characterized in that the at least one flow barrier (400) has an essentially uniform height along its length, which is between 0.5 cm and 10 cm, preferably between 0.8 cm and 9 cm, more preferably between 0.9 cm and 8 cm and most preferably between 1 cm and 7 cm. System (100) according to claim 4, characterized in that the retaining means (200) is configured in such a way that at least within each row, the openings of the containers (300) are arranged within a common plane along the length of the first direction (601) when retained by the retaining means (200); whereby the at least one flow barrier (400) is essentially wall-shaped and whereby the height of the at least one flow barrier (400) is measured in a direction essentially perpendicular to said common plane. System (100) according to any one of the preceding claims, characterized in that the length of the at least one flow barrier (400) in the first direction (601) is between 0.5 cm and 50 cm, preferably between 0 , 8 cm and 40 cm, more preferably between 1 cm and 30 cm, and most preferably between 1 cm and 20 cm. System (100) according to any one of the preceding claims, characterized in that the distance between the at least one flow barrier (400) and the gas outlet is not less than 1 cm, preferably not less than 2 cm, more preferably not less than 3 cm, even more preferably not less than 4 cm, and most preferably not less than 5 cm. System (100) according to any one of the preceding claims, characterized in that the system (100) comprises at least two flow barriers (400) and a source (700) of negative pressure to create a pressure difference between the source ( 700) of negative pressure and the gas outlet in such a way that the gas provided by the one The gas outlet moves towards the negative pressure source (700), the system (100) further comprising a controller to control the negative pressure source (700) in such a way that the gas flow rate between the at least two barriers (400) flow is between 100 and 200 cm3 / s, preferably between 120 and 180 cm3 / s, more preferably between 140 and 170 cm3 / s, and most preferably between 160 and 170 cm3 / s. System (100) according to any one of the preceding claims, characterized in that the system (100) comprises a negative pressure source (700) to create a pressure difference between the negative pressure source (700) and the gas outlet in such a way that the gas provided by the gas outlet moves towards the negative pressure source (700), the system (100) further comprising a controller to control the negative pressure source (700) in such a way that the speed of gas between the gas outlet and the at least one flow barrier (400) is between 0.1 m / s and 0.5 m / s, preferably between 0.2 m / s and 0.5 m / s, and more preferably between 0.3 m / s and 0.5 m / s. System (100) according to any one of the preceding claims, characterized in that the gas outlet is arranged to make the gas flow (501, 503) flow along an initial flow direction, whereby the system (100) further comprises a source (700) of negative pressure arranged in such a way that after having passed at least the openings of all the containers (300) of a row, the flow (501, 503) of gas is directed in one direction different from the starting address. System (100) according to any one of the preceding claims, characterized in that the gas outlet comprises a matrix of orifices. System (100) according to any one of the preceding claims, characterized in that the retaining means (200) comprises a frame (201 ') extending along the first direction (601), the frame (201 ') removably in a main housing (101) of the system (100), the frame being adapted to retain at least two rows of containers (300). System (100) according to any one of the preceding claims, characterized in that the negative pressure source (700) is a pump configured to pump gas at a flow rate that per row of containers 300 is not less than that of the outlet Of gas. one