Patent Application
20170191013
The invention relates to a container for culturing organisms, a method for monitoring the culturing of organisms inside said container and a monitoring system.
Examples of such containers are petri-dishes and microtiter plates usually comprising a holder and a separate lid, said holder defining a cavity for receiving organisms and said lid being configured to close off the cavity.
When culturing microbes, the cavity of the holder may be filled with a matrix or substrate such as agar and a mixture of specific ingredients that may include nutrients, blood, salts, carbohydrates, dyes, indicators, amino acids and/or antibiotics. By inoculating the cavity with a microbe-laden sample, the growth and/or presence of microbes may be monitored.
Although the human eye is still widely used for microbe detection, there is a tendency towards automated systems as they can detect the microbial growth at a much earlier stage and preferably without human intervention. In such automated systems, a camera system may take pictures, preferably microscopic pictures, of the upper surface of the matrix or substrate at different moments in time. By comparing pictures of the same area and identifying visual differences microbial growth can be detected.
A drawback of the automated systems, which use a camera to make pictures of the upper surface of the matrix or substrate, is that the signal-to-noise ratio of the pictures is small.
Hence, it is an object of the invention to increase the signal-to-noise ratio of automated systems used for visually monitoring organism growth in a container.
According to a first aspect of the invention, this object is achieved by a container for culturing organisms, comprising:
An advantage of the container according to the first aspect of the invention is that radiation incident to the window portion in a direction normal to the top surface of the matrix travels in a different direction after reflecting of the window portion than radiation passing the window portion in a direction normal to the top surface of the matrix. In this way radiation reflecting of the window portion, which radiation does not contain relevant information about the content of the container, is separated from radiation reflected of the top surface of the matrix and passing the window portion in a direction normal to the top surface of the matrix, which reflected radiation carries information about the presence of organism growth on the top surface of the matrix, so that a camera capturing the reflected radiation is subject to a higher signal-to-noise ratio compared to prior art containers in which the upper and lower surfaces of the window portion are parallel to the top surface of the matrix.
The container may have any shape in top view, including rectangular and circular shapes, but other shapes are also envisaged.
In an embodiment, the holder defines a supporting surface for supporting the holder, and wherein the top surface of the matrix extends parallel to the supporting surface. This has the advantage that the container does not have to be oriented properly with respect to a camera of a monitoring system to obtain a proper image. Once the camera is aligned with a support engaging with the supporting surface of the container, the camera is also automatically aligned with the top surface of the matrix of a container positioned on the support.
In an embodiment, the holder defines a supporting surface for supporting the holder, wherein the cavity is delimited by a bottom surface, and wherein the bottom surface extends parallel to the supporting surface.
In an embodiment, the holder defines a supporting surface for supporting the holder, and wherein in said at least one position the upper and lower surfaces of the window portion extend parallel to the supporting surface. This has the advantage that the container can easily be stacked.
The supporting surface defined by the holder, such that the holder can be supported from a support, e.g. a table, may be formed by a single support surface engaging with the support, but may also be formed by multiple separate support surfaces, e.g. due to the use of legs, feet, pins or the like, wherein the multiple support surfaces lie in the same plane. Hence, alternatively it can be said that the top surface of the matrix, the bottom surface of the cavity and/or the upper and lower surfaces of the window portion are parallel to the plane defined by the one or more support surfaces.
In an embodiment, the top surface of the matrix extends non-parallel to the upper and lower surfaces of the window portion in all angular positions of the lid with respect to the holder in which angular positions the lid closes off the cavity. This has the advantage that the container is always configured for optimal monitoring by a monitoring system.
In an embodiment, the container is configured such that in at least one other position of the lid with respect to the holder, in which the lid closes off the cavity of the holder, the upper and lower surfaces of the window portion are substantially parallel to the supporting surface defined by the holder for stacking purposes. This embodiment has the advantage that the container has two configurations, one in which the container is optimal for monitoring by a monitoring system and one in which the containers can be stacked.
In an embodiment, the lid and holder are identical. This makes the fabrication of the container easy, as only one type of component needs to be fabricated, wherein two of these components can form a container according to the first aspect of the invention.
In an embodiment, the holder defines multiple cavities, wherein the lid is configured to close off the multiple cavities. As a result, multiple cavities can be handled at the same time by handling the container, thereby increasing the speed of the monitoring system. In other words, the holder may define multiple cavities, preferably arranged in an array, as in microtiter plates. In case of multiple cavities, the cavities may be closed off by a single lid comprising a window portion for each cavity, or each cavity has its own separate lid.
It is explicitly noted here that closing off the cavity is not to be interpreted as not allowing any ventilation. Closing off the cavity is to be interpreted such that the content in the cavity is not easily accessible by a user.
In an embodiment, the holder comprises only one cavity as in a traditional petri dish.
In an embodiment, the container comprises glass and/or plastic. Besides the window portion being transparent, the entire lid may transparent. The holder may be transparent, but may also be opaque.
In an embodiment, the container is a shallow container, such that the thickness of the container is at most 0.5 times a width or a length of the container, preferably 0.3 times the width or length, and more preferably at most 0.2 times the width or length.
In an embodiment, the upper and lower surface of the window portion make an angle with the top surface of the matrix in the range of 10-200 mrad.
In an embodiment, the holder comprises a bottom portion arranged below the cavity, said bottom portion comprising a bottom surface delimiting the cavity and a lower surface opposite the bottom surface, wherein the bottom surface and the lower surface of the bottom portion extend parallel to each other. As a result thereof the bottom portion at the cavity has a constant thickness thereby reducing optical disturbances caused by the bottom portion.
In an embodiment, the bottom portion is free of text, drawings, symbols, prints and the like. This will keep the optical disturbances to a minimum.
In an embodiment, the bottom surface and the lower surface of the bottom portion extend non-parallel to the top surface of the matrix. In this way, any reflections of the bottom surface and/or lower surface of the bottom portion are separated from the reflection of interest of the top surface of the matrix.
In an embodiment, the bottom surface and the lower surface of the bottom portion extend parallel to the upper and lower surfaces of the window portion. In this way, the behaviour of reflections of the bottom surface and the lower surface of the bottom portion and the reflections of the upper and lower surfaces of the window portion is similar.
In an embodiment, the bottom portion comprises light absorbing material to reduce the optical disturbances caused by the bottom portion.
The second aspect of the invention also relates to a method for monitoring the culturing of organisms in a container, said method comprising the following steps:
In an embodiment, light is directed towards the top surface of the matrix through the window portion in a direction perpendicular to the top surface of the matrix to be reflected of the top surface and to be captured to make the image.
In an embodiment, the container is configured such that in a first position of the lid with respect to the holder, in which the lid closes off the cavity of the holder, the upper and lower surfaces of the window portion are substantially parallel to the top surface of the matrix, and such that in a second position of the lid with respect to the holder, in which the lid closes off the cavity of the holder, the upper and lower surfaces of the window portion are substantially non-parallel to the top surface of the matrix, and wherein the method comprises the step of providing the lid in the second position prior to step d.
In an embodiment, step d. is performed at different moments in time and the method further comprises the step of comparing images of the same area for visual differences indicating organism growth.
The first aspect of the invention further relates to a monitoring system for monitoring the culturing of organisms, said monitoring system comprising:
In an embodiment, the objective comprises a telecentric lens.
According to a second aspect of the invention, the object is achieved by a container for culturing organisms, comprising:
An advantage of the container according to the second aspect of the invention is that radiation incident to the window portion in a direction normal to the bottom surface after reflecting of the window portion travels in a different direction than radiation passing the window portion in a direction normal to the bottom surface. In this way radiation reflecting of the window portion, which radiation does not contain relevant information about the content of the container, is separated from radiation passing the window portion in a direction normal to the bottom surface, which radiation carries information about the content of the container, so that a camera capturing the information carrying radiation is subject to a higher signal-to-noise ratio compared to prior art containers in which the upper and lower surfaces of the window portion are parallel to the bottom surface.
The container may have any shape including rectangular and circular shapes, but other shapes are also envisaged.
The holder may define a single cavity as in a traditional petri dish, but may also define multiple cavities, preferably arranged in an array, as in microtiter plates. In case of multiple cavities, the cavities may be closed off by a single lid comprising a window portion for each cavity, or each cavity has its own separate lid.
The supporting surface defined by the holder such that the holder can be supported from a support element, e.g. a table, may be formed by a single support surface engaging with the support element, but may also be formed by multiple separate support surfaces, e.g. due to the use of legs, feet, pins, and/or the like, wherein the multiple support surfaces lie in the same plane. Hence, alternatively it can be said that the bottom surface of the cavity defined by the holder is parallel to the plane defined by the one or more support surface.
In an embodiment, the container is a petri dish or a microtiter plate.
In an embodiment, the container comprises glass and/or plastic.
In an embodiment, the entire container is made of transparent material.
In an embodiment, the container is a shallow container, wherein a thickness of the container is at most 0.5 times a width or a length of the container, preferably at most 0.3 times the width or length, and more preferably at most 0.2 times the width or length.
In an embodiment, the holder defines an engagement surface for engaging with the lid when the lid closes off the cavity, wherein the engagement surface is parallel to the supporting surface.
In an embodiment, the holder defines an engagement surface for engaging with the lid when the lid closes off the cavity, wherein the engagement surface is non-parallel to the supporting surface.
In an embodiment, the engagement surface is parallel to the upper surface and the lower surface of the window portion.
In an embodiment, the engagement surface is non-parallel to the upper surface and the lower surface of the window portion.
In an embodiment, the container is configured such that in at least one other position of the lid with respect to the holder, in which the lid closes off the cavity of the holder, the upper and lower surfaces of the window portion are substantially parallel to the bottom surface of the cavity for stacking purposes.
In an embodiment, the lid and holder are identical.
In an embodiment, the cavity is filled with a matrix, wherein an upper surface of the matrix is parallel to the supporting surface.
In an embodiment, the upper and lower surface of the window portion make an angle with the bottom surface of the cavity in the range of 10-100 mrad, preferably 75 mrad.
In an embodiment, the lid comprises a first part and a separate second part, wherein when the lid closes off the cavity, the second part is arranged in between the first part and the holder and causes the upper and lower surfaces of the window portion to extend non-parallel to the bottom surface.
In an embodiment, the first part is able to close off the cavity without using the second part, in which case the upper and lower surfaces of the window portion are parallel to the bottom surface.
The second aspect of the invention also relates to a method for monitoring the culturing of organisms in a container, comprising the following steps:
In an embodiment, the container is configured such that in a first position of the lid with respect to the holder, in which the lid closes off the cavity of the holder, the upper and lower surfaces of the window portion are substantially parallel to the bottom surface of the cavity, and such that in a second position of the lid with respect to the holder, in which the lid closes off the cavity of the holder, the upper and lower surfaces of the window portion are substantially non-parallel to the bottom surface of the cavity, and wherein the method comprises the step of providing the lid in the second position prior to step d.
In an embodiment, step d. is performed at different moments in time and the method further comprises the step of comparing images of the same area for visual differences indicating organism growth.
The second aspect of the invention further relates to a monitoring system for monitoring the culturing of organisms, said monitoring system comprising:
In an embodiment, the objective comprises a telecentric lens.
The invention according to the first and second aspect will now be described by reference to the accompanying drawings in which like parts are indicated by like reference symbols, and in which:
The light source LS is configured to provide a radiation beam RB to the objective OB, which objective OB comprises an optical element OE to direct the radiation beam parallel to an optical axis of the objective. Hence, light is emitted from the objective. The objective is configured to capture an image of reflected light, which light passes the optical element OE and is incident to a detector DE of the camera CA.
The prior art monitoring system uses prior art containers CO for culturing organisms, wherein the container CO comprises a holder HO and a lid L. The holder HO defines a supporting surface SS for supporting the holder HO, in this embodiment, of a support ST. The holder HO further defines a cavity CV for receiving an organism OR to be cultured, said cavity being delimited at one side by a bottom surface BS that is parallel to the supporting surface SS. The cavity CV is further delimited by a sidewall SW.
In this embodiment, the cavity is filled with a matrix, in this case a layer of agar AG, preferably comprising specific ingredients such as nutrients, blood, salts, carbohydrates, dyes, indicators, amino acids and/or antibiotics. Agar is usually provided to the container in warm liquid form. Once the agar solidifies it can be inoculated with an organism-laden sample. The inoculated organism may be the organism of interest, but the organism may also be provided as a host for a virus or phage, so that a second inoculation is required to introduce the virus or phage of interest. The agar will have a top surface TS that is substantially parallel to the supporting surface SS and the bottom surface BS.
The lid L is separate from the holder HO in that it is not connected to the holder HO via hinges or any other structure. The lid L can thus be separated from the holder HO without damaging the container. The lid is configured to close off the cavity so that the organism can be cultured without the risk of contamination. The content of the cavity may for instance not be contaminated by airborne particles and organisms in the environment of the container, but alternatively or additionally the environment may not be contaminated by the organisms inside the cavity of the container.
The lid comprises a transparent window portion WP to be arranged above the cavity CV when the lid L closes off the cavity CV, wherein said window portion WP comprises an upper surface USU and a lower surface LSU extending parallel to each other and parallel to the top surface TS, the supporting surface SS and the bottom surface BS.
When the container CO is positioned beneath the monitoring system of
It may be obvious to improve the signal-to-noise ratio by removing the cause of the reflections. That is, the lid is removed of the holder during monitoring by the monitoring system. This is why the lid is drawn in dashed lines in
Another, possibly obvious, solution may be provided by looking at the solutions provided by users of microscopes which also try to look at the organism through the lid. From this field it is known to tilt the entire container. This may cause the reflections to be directed away from the objective, so that they cannot be captured by the objective, but makes positioning and orienting the matrix relative to the camera and objective more challenging. Hence, these solutions are also not preferred.
The inventors have come up with the idea to adjust the container, such that in at least one position of the lid with respect to the holder, in which the lid closes off the cavity of the holder, the upper and lower surfaces of the window portion are substantially non-perpendicular to the light emitted by the camera, i.e. are non-perpendicular to an optical axis defined by the objective. This will be explained in more detail with respect to
As in
The light source LS is configured to provide a radiation beam RB to the objective OB, which objective OB comprises an optical element OE to direct the radiation beam parallel to an optical axis of the objective. Hence, light is emitted from the objective. The objective is configured to capture an image of reflected light, which light passes at least partially the optical element OE and is incident to a detector DE of the camera CA. An output OP of the detector DE is processed in a processing unit PU.
The monitoring system is used in combination with a container CO according to an embodiment of the invention for culturing organisms, wherein the container CO comprises a holder HO and a lid L. The holder HO defines a supporting surface SS for supporting the holder HO, in this embodiment, from a support ST. The holder HO further defines a cavity CV for receiving an organism OR to be cultured, said cavity being delimited at one side by a bottom surface BS that in this embodiment is parallel to the supporting surface SS. The cavity CV is further delimited by a sidewall extending from the bottom surface BS, which sidewall comprises a first sidewall portion SW1 and an second sidewall portion SW2 opposite to the first sidewall portion SW1.
In this embodiment, the cavity is filled with matrix, e.g. a layer of agar AG preferably comprising specific ingredients such as nutrients, blood, salts, carbohydrates, dyes, indicators, amino acids and/or antibiotics. Agar is usually provided to the container in a warm liquid form. Once the agar solidifies it can be inoculated with an organism-laden sample. The inoculated organism may be the organism of interest, but the organism may also be provided as a host for a virus or phage, so that a second inoculation is required to introduce the virus or phage of interest. The agar AG has a top surface TS that is in this embodiment substantially parallel to the supporting surface SS an the bottom surface BS.
The lid L is separate from the holder HO in that it is not connected to the holder HO via hinges or any other structure. The lid L can thus be separated from the holder HO without damaging the container. The lid is configured to close off the cavity so that the organism can be cultured without the risk of contamination.
The lid comprises a transparent window portion WP to be arranged above the cavity CV when the lid L closes off the cavity CV, wherein said window portion WP comprises an upper surface USU and a lower surface LSU extending parallel to each other.
The container CO is configured such that in at least one position of the lid L with respect to the holder HO, in which the lid L closes off the cavity CV of the holder HO, the upper and lower surfaces USU, LSU of the window portion WP are substantially non-parallel to the bottom surface BS of the cavity CV, i.e. the upper and lower surfaces USU, LSU of the window portion make a non-zero angle α with the bottom surface BS. Hence,
In the embodiment of
When the container CO is positioned beneath the monitoring system of
Radiation is also partially reflected of the upper surface USU and the lower surface LSU of the window portion WP. However, due to the tilt of the lid with respect to the horizontal the reflected radiation RR is reflected away from the vertical at an angle substantially equal to 2*α, which prevents the objective OB from capturing the reflected radiation RR when the numerical aperture of the objective is smaller than angle α, which increases the signal-to-noise ratio.
The embodiment of
In an embodiment, the objective OB may be telecentric.
The container CO further comprises a separate lid L to close off the cavity CV, said lid L comprising a transparent window portion WP to be arranged above the cavity CV when the lid L closes off the cavity CV, as shown in
The container CO is configured such that in at least one position of the lid L with respect to the holder HO, in which the lid L closes off the cavity CV of the holder HO, the upper and lower surfaces USU, LSU of the window portion WP are substantially non-parallel to the bottom surface BS of the cavity CV, i.e. the upper and lower surfaces USU, LSU of the window portion WP make a non-zero angle α with the bottom surface BS. Hence,
The cavity CV is filled with a matrix or substrate, in this embodiment agar AG with additives enabling the growth of organisms on the agar AG. The agar is a layer of material having a top surface TS extending in this embodiment parallel to the bottom surface BS. Hence,
In the embodiment of
In the embodiment of
In the embodiments of both
The container CO further comprises a separate lid L to close off the cavity CV, said lid L comprising a transparent window portion WP to be arranged above the cavity CV when the lid L closes off the cavity CV, as shown in both configurations of
The holder HO comprises a sidewall including a first sidewall portion SW1 and a second sidewall portion SW2, wherein the height of the second sidewall portion is larger than the height of the first sidewall portion.
The lid comprises a sidewall including a third sidewall portion SW3 and a fourth sidewall portion SW4, wherein the height of the fourth sidewall portion SW4 is larger than the height of the third sidewall portion SW3.
The container is configured such that in a first position of the lid L with respect to the holder HO corresponding to configuration A in which the lid closes off the cavity, the upper surface USU and the lower surface LSU are parallel to the bottom surface. This configuration is advantageous as it allows stacking of multiple containers CO when the containers are all in configuration A. Configuration A may be obtained by choosing the sum of the heights of the first and fourth sidewall portions SW1, SW4 to be equal to the sum of the heights of the second and third sidewall portions SW2, SW3.
Configuration B depicts a second position of the lid L with respect to the holder HO. In configuration B, the lid is rotated 180 degrees with respect to configuration A about an axis perpendicular to the bottom surface BS. Hence, the fourth sidewall portion SW4 is situated above the second sidewall portion SW2 and the third sidewall portion SW3 is situated above the first sidewall portion SW1. As the fourth and second sidewall portions SW4, SW2 are larger than the corresponding third and first sidewall portions SW3, SW1, the upper and lower surfaces USU, LSU of the window portion WP are substantially non-parallel to the bottom surface BS of the cavity CV, i.e. the upper and lower surfaces USU, LSU of the window portion WP make a non-zero angle α with the bottom surface BS, in the second position of the lid with respect to the holder. Hence,
The cavity CV is filled with a matrix or substrate, in this embodiment agar AG with additives enabling the growth of organisms on the agar AG. The agar is a layer of material having a top surface TS extending in this embodiment parallel to the bottom surface BS. Hence,
In the embodiment of
In an embodiment closely related to the embodiment shown in
The container CO further comprises a separate lid L to close off the cavity CV. In this embodiment, the lid L comprises a first part L1 and a second part L2. When the lid closes off the cavity, the second part L2 is arranged in between the holder HO and the first part L1. The first and second part L1, L2 may be separate components that are to be assembled when the cavity CV needs to be closed.
An advantage of using a lid L with two parts L1, L2, is that the first part L1 and the holder may be formed by a prior art container, e.g. a petri dish, which is adapted by providing and using the second part L2 dedicated for implementing the invention.
The first part L1 of the lid L comprises a transparent window portion WP to be arranged above the cavity CV when the lid L closes off the cavity CV, as shown in
The container CO is configured such that in at least one position of the lid L with respect to the holder HO, in which the lid L closes off the cavity CV of the holder HO, the upper and lower surfaces USU, LSU of the window portion WP are substantially non-parallel to the bottom surface BS of the cavity CV, i.e. the upper and lower surfaces USU, LSU of the window portion WP make a non-zero angle α with the bottom surface BS. Hence,
The cavity CV is filled with a matrix or substrate, in this embodiment agar AG with additives enabling the growth of organisms on the agar AG. The agar is a layer of material having a top surface TS extending in this embodiment parallel to the bottom surface BS. Hence,
In the embodiment of
In the embodiments of
The container CO further comprises a separate lid L to close off the cavity CV, said lid L comprising a transparent window portion WP to be arranged above the cavity CV when the lid L closes off the cavity CV, as shown in
The cavity CV is filled with a matrix or substrate, in this embodiment agar AG with additives enabling the growth of organisms on the agar AG. The agar is a layer of material having a top surface TS extending in this embodiment non-parallel to the upper and lower surfaces USU, LSU of the window portion WP. Hence,
The container CO further comprises a separate lid L to close off the cavity CV, said lid L comprising a transparent window portion WP to be arranged above the cavity CV when the lid L closes off the cavity CV, as shown in
The cavity CV is filled with a matrix or substrate, in this embodiment agar AG with additives enabling the growth of organisms on the agar AG. The agar is a layer of material having a top surface TS extending in this embodiment non-parallel to the upper and lower surfaces USU, LSU of the window portion WP. Hence,
An advantage of the tilted window portion of the lid and the tilted bottom portion of the holder is that when radiation incident to these parts in a direction normal to the top surface of the agar is reflected, the radiation is reflected in a different direction than radiation reflecting of the top surface of the agar and passing the window portion towards a camera of a monitoring system.
Although the description and examples are about arranging organisms on a top surface of a matrix or substrate, the invention is not limited to only arranging the organisms on this top surface. It is thus also possible that a filter is provided on top of the matrix or substrate, wherein the organisms are positioned on top of the filter, and wherein the filter is permeable for components of the matrix or substrate, so that the organisms can use these components for culturing.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012922 | May 2014 | NL | national |
This application is the National Stage of International Application No. PCT/NL2015/050384 filed May 28, 2015, which claims the benefit of Netherlands Application No. NL 2012922, filed May 30, 2014, the contents of which is incorporated by reference herein.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/NL2015/050384 | 5/28/2015 | WO | 00 |
