Culture dish for microorganisms

Abstract

Container for cultivating cells comprising a bottom, a circumferential vertical outer wall and a self-contained vertical inner wall, wherein the area enclosed by the inner wall has a diameter that is at least slightly smaller than the area enclosed by the circumferential outer wall.

Description

[0001] The present invention relates to a container for cultivating cells, comprising a base, a circumferential vertical outer wall, and a self-contained vertical inner wall, wherein the area enclosed by the annular inner wall has an at least slightly smaller diameter than the area enclosed by the circumferential outer wall. Furthermore, the present invention relates to the use of the container for cultivating cell cultures or microorganisms.

[0002] Containers for culturing microorganisms are commonly referred to as Petri dishes or contact plates and are well known in the art. Containers typically have a lower container in the form of a tray for the growth medium. The lower container is usually used in conjunction with a lid that fits over the side wall of the lower container. A contact plate is a much smaller version of a Petri dish, the tray portion of which is pre-filled with a growth medium and typically provided with a base for gripping the contact plate so that it can be pressed against a surface to obtain a sample of the microorganisms present on the surface under investigation. Containers such as these are mass-produced by several manufacturers. Typically, the trays are made of polymer material and are disposed of after a single use.The tray area of ​​the contact plate is filled with a substantially convex mound of growth medium. After removing the lid, the contact plate is grasped at its base and the growth medium mound is pressed against a surface to be tested for bacterial and / or fungal growth. The lid is then replaced, and the contact plate is stored in an environment conducive to the growth of microorganisms. A typical contact plate is filled with growth medium under sterile conditions and packaged for delivery to the end user.

[0003] Petri dishes and contact plates are available in various sizes. The size for the respective application is sometimes officially specified (e.g., in the European Pharmacopoeia, Pharmacopoea Europaea).

[0004] For example, in the European Pharmacopoeia, Chapter 2.6.7 (Detection of Mycoplasmas) states that a certain number of microorganisms should be applied to a dish with a diameter of 60 mm containing 9 ml of solid medium.

[0005] The difficulty for the container manufacturer is that the production machines have to be adapted to a different plate format after each production run.

[0006] The object of the present invention was therefore to find a solution to simplify the manufacturing process of different container sizes.

[0007] It has now been found that this problem can be solved by a "shell-in-shell concept" in which the dimension of the outer shell is adapted to the production machines, while the dimension of the inner shell differs from that of the outer shell and corresponds to the desired usage size.

[0008] A first object of the present invention is therefore a container for cultivating cells comprising a bottom, a circumferential vertical outer wall and a self-contained vertical inner wall, wherein the area enclosed by the annular inner wall has an at least slightly smaller diameter than the area enclosed by the circumferential outer wall.

[0009] In other words, it's a shell within a shell. The self-contained vertical inner wall can be, for example, a ring, a rectangle, or similar structures.

[0010] The container is preferably in the form of a Petri dish, contact plate or sedimentation plate.

[0011] Preferably, the diameter of the area enclosed by the peripheral outer wall (ie the inner diameter of the outer shell) is 8.5 to 9.5 cm, which corresponds to an area of ​​56.7 to 70.8 cm 2This dimension is tailored to the respective production machines. The diameter is particularly preferred to be 8.8 cm. The container preferably has a round base; however, any other shapes, such as rectangular or trapezoidal bases, are also conceivable.

[0012] The diameter of the area enclosed by the inner wall is preferably 3 to 8 cm. The diameter is particularly preferably 5 to 7 cm, and most preferably 5.5 cm. This inner shell corresponds to the desired / prescribed dimensions for its use. The area enclosed by the inner wall is preferably round, i.e., the inner wall is preferably ring-shaped. However, any other shapes, such as rectangular or trapezoidal surfaces, are also conceivable.

[0013] In a preferred embodiment, the outer and inner walls are designed in the form of two concentric circles.

[0014] Typically, the thickness of the circumferential outer wall and the thickness of the inner wall are independently 0.4 to 1 mm, preferably 0.5 to 0.7 mm.

[0015] The height of the outer wall and the inner wall can be the same or different from each other. Preferably, the height is the same. Typically, the height of the walls is independently between 10 and 30 mm. Preferably, the height is between 10 and 15 mm, particularly preferably 12 mm.

[0016] In a preferred embodiment, the container has a removable lid. The lid is preferably designed such that it has a circumferential wall that extends over / encompasses the outer wall of the container. The lid preferably has the same basic shape as the container. The lid is preferably designed such that it completely closes and / or seals the container. In one embodiment, the lid hermetically seals the container, preventing gas exchange. In an alternative embodiment, gas or moisture exchange with the environment is still ensured after closure.

[0017] The closed container is preferably cylindrical or approximately cylindrical. This means that slightly conical shapes are also included in the term "cylindrical."

[0018] Preferably, the container is made of a transparent material such as glass or plastic, particularly preferably of transparent plastic such as polystyrene, polyethylene, polypropylene or polycarbonate, which can be formed using conventional injection molding techniques or thermoplastic techniques.

[0019] For use in cultivation, the inner dish, i.e. the dish formed by the inner wall and base, must be filled with a suitable growth or culture medium. A growth medium serves to support the growth of microorganisms and is available in various formulations depending on the type of organism. Typically, agar is used in the formulation for contact plates or Petri dishes to achieve a gel-like, solid consistency of the growth medium. Common formulations are based, for example, on CASO agar with or without inhibitors such as lecithin and polysorbate, Sabouraud dextrose agar with or without inhibitors, or DE Neutralizing Agar, which is supplemented with a mixture of nutrients, salts, amino acids, and optionally antibiotics. It is therefore not difficult for the expert to select the right media for the respective application.

[0020] A further object of the present invention relates to the use of a container as defined above for cultivating cell cultures or microorganisms, in particular bacteria or yeasts.

[0021] In general, there are no restrictions on the use of the container according to the invention. For example, it can be used for routine experiments, in vivo tests, total microbial count determinations, sterility determinations, etc.

[0022] Fig. shows a simplified schematic representation of an embodiment of the container according to the invention in plan view. The inner wall (1) encloses an inner area (2). This area is filled with nutrient medium. The area (4), which is enclosed by the outer wall (3) and the inner wall (1), remains empty.

Claims

[1] Container for cultivating cells comprising a bottom, a circumferential vertical outer wall and a self-contained vertical inner wall, wherein the area enclosed by the inner wall has an at least slightly smaller diameter than the area enclosed by the circumferential outer wall. [2] Container according to claim 1, characterized by that the container is in the form of a Petri dish, contact plate or sedimentation plate. [3] Container according to claim 1 or 2, characterized by that the diameter of the area enclosed by the surrounding outer wall is 8.5 to 9.5 cm. [4] Container according to one or more of claims 1 to 3, characterized by that the diameter of the area enclosed by the inner wall is 3 to 8 cm. [5] Container according to one or more of claims 1 to 4, characterized by that the thickness of the surrounding outer wall is 0.4 to 1 mm. [6] Container according to one or more of claims 1 to 5, characterized by that the thickness of the inner wall is 0.4 to 1 mm. [7] Container according to one or more of claims 1 to 6, characterized by that the container has a removable lid. [8] Container according to claim 7, characterized by that the lid has a surrounding wall that extends over / around the outer wall of the container. [9] Container according to one or more of claims 1 to 8, characterized by that the container is made of transparent material, preferably transparent plastic. [10] Container according to one or more of claims 1 to 9, characterized by that the inner shell formed by the inner wall and the bottom is filled with culture medium, preferably with agar. [11] Use of a container according to one or more of claims 1 to 10 for cultivating cell cultures or microorganisms, in particular bacteria or yeasts.

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