Bacteria collector and experimental method

Abstract

The invention relates to a bacteria collector which comprises a tray, a film pressing piece, a water absorption pad and a bacteria filtering film, the bacteria filtering film comprises a first filtering part, a second filtering part surrounding the periphery of the first filtering part and a mounting part surrounding the periphery of the second filtering part, the film pressing piece is detachably connected with the tray, and the mounting part is pressed on the tray through the film pressing piece; the water absorption pad is arranged on the lower side of the first filtering part and can absorb water on the first filtering part, the second filtering part is suspended, and when the film pressing piece is loosened, the bacteria filtering film can be taken out from the tray. The invention further provides an experimental method. The bacterium collector has the advantages of being simple in structure, easy to operate, low in use cost, good in use effect and wide in use range, and positive pressure or negative pressure does not need to be manually applied. The experimental method provided by the invention has low requirements on instruments, consumables and sample size, and has the characteristic of easiness in implementation.

Description

Technical Field

[0001] The invention relates to the field of experimental technology, and in particular to a bacteria collector and an experimental method. Background Art

[0002] In the prior art, the pouring method and the membrane filtration method are both commonly used colony counting methods. The pouring method is time-consuming and labor-intensive, and the membrane filtration method requires special filtration equipment and a matching filtration cup, which has high requirements for instruments and consumables, or requires manual pressure filtration with a syringe, which is cumbersome to operate. In addition, the membrane filtration method has the problems of high consumables cost and large sample demand. Summary of the invention

[0003] The object of the present invention is to provide a bacteria collector and an experimental method, which are helpful to alleviate or eliminate at least one of the above-mentioned technical problems.

[0004] A bacteria collector described in the present invention includes a tray, a film pressing piece, a water-absorbing pad and a bacteria filter membrane. The bacteria filter membrane includes a first filtering part, a second filtering part surrounding the first filtering part, and an installation part surrounding the second filtering part. The film pressing piece can be loosely connected to the tray, and the film pressing piece presses the installation part onto the tray. The water-absorbing pad is placed on the lower side of the first filtering part. The water-absorbing pad can naturally absorb moisture on the first filtering part and the second filtering part. The second filtering part is suspended in the air. When the film pressing piece is loosened, the bacteria filter membrane can be taken out from the tray.

[0005] Optionally, the tray is provided with a first supporting portion and a second supporting portion spaced apart and surrounding the first supporting portion, the water absorbent pad is supported on the first supporting portion, and a spacing space is provided between the water absorbent pad and the second supporting portion, the first filtering portion covers the water absorbent pad, the mounting portion is pressed against the second supporting portion by the film pressing member, and the second filtering portion is suspended on the upper side of the spacing space.

[0006] Optionally, a limiting portion is disposed on the periphery of the first supporting portion, and the limiting portion and the first supporting portion constitute a mounting groove for mounting the water absorbent pad.

[0007] Optionally, there is a gap between the upper end of the limiting portion and the bacteria filtering membrane.

[0008] Optionally, the first filtering part, the second filtering part and the installation part are connected in sequence.

[0009] Optionally, the film pressing member is provided with an annular film pressing portion for pressing the installation portion downward.

[0010] Optionally, the die pressing member is detachably connected to the tray.

[0011] Optionally, the tray and the film pressing member are connected to form a cavity with an open upper side, and the bacteria collector further includes a cover for covering the opening of the cavity.

[0012] Optionally, the tray includes a tray bottom wall and a tray side wall extending upward from an edge of the tray bottom wall.

[0013] The present invention also proposes an experimental method, using any of the above-mentioned bacteria collectors, comprising the following steps: Add the sample liquid onto the bacterial filter membrane, and spread or shake the sample liquid; After the water in the sample liquid on the bacterial filter membrane is filtered out, the bacterial filter membrane is taken out and attached to the surface of the agar culture medium for cultivation; After the culturing, the colonies grown on the bacteria filter membrane are observed and identified or the colonies grown on the bacteria filter membrane are counted.

[0014] The bacteria collector proposed by the present invention has the characteristics of simple structure, simple operation, low use cost, good use effect and wide use range. The experimental method proposed by the present invention has low requirements on instruments, consumables and sample quantity and is easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a cross-sectional view of a bacteria collector described in some embodiments; Figure 2 for Figure 1 A partial enlarged view of Figure 3 An exploded view of a bacteria collector described in some embodiments; Figure 4 is a top view of a tray described in some embodiments; Figure 5 Schematic diagram of bacterial colonies growing on filter membrane; Figure 6 Schematic diagram of the bacterial filter membrane attached to the surface of the agar culture medium for cultivation.

[0016] Among them: 1-tray, 2-absorbent pad, 3-bacteria filter membrane, 4-film pressing piece, 5-lid, 6-culture dish, 7-agar culture medium, 8-colony, 101-tray bottom wall, 102-tray side wall, 103-first supporting portion, 104-second supporting portion, 105-interval, 106-limiting portion, 107-installing groove, 301-first filtering portion, 302-second filtering portion, 303-installing portion, 304-first dotted line, 305-second dotted line, 401-annular film pressing portion, 402-connecting section, 403-operating section. DETAILED DESCRIPTION

[0017] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0018] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0019] like Figures 1 to 5 A bacteria collector shown in the figure includes a tray 1, a film pressing member 4, a water-absorbing pad 2 and a bacteria filter membrane 3. The bacteria filter membrane 3 includes a first filtering part 301, a second filtering part 302 surrounding the first filtering part 301 and a mounting part 303 surrounding the second filtering part 302. The film pressing member 4 is releasably connected to the tray 1, and the film pressing member 4 presses the mounting part 303 onto the tray 1. The water-absorbing pad 2 is placed on the lower side of the first filtering part 301. The water-absorbing pad 301 can naturally absorb moisture on the first filtering part 301 and the second filtering part 302. The second filtering part 302 is suspended in the air. When the film pressing member 4 is released, the bacteria filter membrane 3 can be taken out from the tray 1.

[0020] By using the above-mentioned bacteria collector, the absorbent pad 2 can absorb the moisture of the sample liquid on the first filter part 301 and the second filter part 302, and the sample liquid on the second filter part 302 can also be absorbed by the absorbent pad. Most of the bacteria in the sample liquid on the second filter part 302 are retained on the second filter part 302 to prevent too much sample liquid from approaching the edge of the filter membrane 3 due to tension, resulting in excessive accumulation of bacteria on the edge and not being dispersed, making it difficult to observe and identify. Within a short period of time (usually a few minutes), the moisture of the sample liquid on the first filter part 301 and the second filter part 302 can be filtered out, and the bacteria in the sample liquid are intercepted on the first filter part 301 and the second filter part 302.

[0021] Since the mounting part 303 is pressed on the tray 1 by the membrane pressing member 4, the tension of the second filtering part 302 near the edge of the mounting part 303 on the bacterial filter membrane 3 is relatively large, resulting in excessive liquid in the dead corner of the edge of the second filtering part 302 and increased filtering efficiency. If a water absorbing member is also provided on the lower side of the second filtering part 302, the filtering efficiency of the second filtering part 302 will be too high, which will lead to excessive filtering of sample liquid at the second filtering part 302, excessive bacteria intercepted by the second filtering part 302, and the colonies 8 at the second filtering part 302 will be accumulated linearly, usually in a circular linear accumulation, making it difficult or even impossible to count the colonies 8. In this embodiment, the water absorbent pad 2 is arranged at the lower side of the first filter part 301, which can ensure the filtering efficiency of the first filter part 301, and the second filter part 302 is suspended above the tray 1, which can prevent the filtering efficiency of the second filter part 302 from being too high, so that the filtering efficiency of the first filter part 301 and the second filter part 302 is more balanced, so that the bacteria distribution of the bacteria filter membrane 3 is more uniform during the experiment, thereby ensuring that the colonies 8 can be more evenly distributed on the bacteria filter membrane 3, and preventing the occurrence of linear accumulation of colonies 8. It is precisely by suspending the second filter part 302 that the above-mentioned bacteria collector can be actually applied to the experiment.

[0022] In the above-mentioned bacteria collector, by providing a membrane pressing member 4, the bacteria filter membrane 3 can be pressed tightly on the tray 1, which provides convenience for spreading or shaking the sample liquid. The above-mentioned bacteria collector can be applied to colony counting experiments, especially for colony counting experiments of 1ml sample liquid. When conducting a colony counting experiment, 1ml sample liquid is added to the bacteria filter membrane 3, and the sample liquid is spread or shaken; after a short time (usually a few minutes), the water in the sample liquid is absorbed and filtered, and then the bacteria filter membrane 3 can be taken out and attached to the surface of the agar culture medium 7 for cultivation; after cultivation, the colonies 8 grown on the bacteria filter membrane 3 can be counted.

[0023] The above-mentioned bacteria collector is used to carry out colony counting experiments, isolation and cultivation of target bacteria and evaluation of disinfection effect (reduction in the number of bacteria on the membrane before and after disinfection), which can replace the cumbersome pouring method in the prior art and has the characteristics of simple structure, simple operation and low cost of use.

[0024] The above-mentioned bacteria collector uses an absorbent pad 2 to absorb moisture in the sample liquid. There is no need to apply negative pressure or positive pressure. It uses gravity and microporous capillaries to absorb moisture in the sample liquid. It has low requirements for instruments, consumables and sample volume, and has the characteristics of cost saving, time saving, easy implementation and easy operation.

[0025] The above-mentioned bacteria collector uses the bacteria filter membrane 3 to filter and collect bacteria, and does not require centrifugation operation. It can replace the centrifugation method, and there is no laboratory contamination and infection risk caused by aerosols. It is simpler and safer, which is conducive to improving the positive rate and detection rate. The bacteria filter membrane 3 after collecting bacteria can be horizontally attached to the corresponding screening and selective agar culture medium 7 according to the purpose of bacterial culture inspection. There are a variety of screening and selective culture media to choose from, such as: screening culture media for various multi-drug resistant bacteria in various hospital room environments, which greatly improves the positive rate and detection rate, and also greatly expands the detection range.

[0026] In addition to being used for colony counting, the above-mentioned bacteria collector can also be used for screening of special bacterial species. For example, the filter membrane after natural adsorption and filtration of the sample can be attached to SS (Screen-Shigella agar medium) and cultured to achieve screening of Salmonella and Shigella in food. The above-mentioned bacteria collector can quantitatively add bacterial suspension to simply and quickly form quantitative bacterial slices for testing and verification of disinfection effects.

[0027] In some embodiments, the tray 1 is provided with a first support portion 103 and a second support portion 104 which is spaced and surrounds the periphery of the first support portion 103, the water absorbent pad 2 is supported on the first support portion 103, and there is a spacing space 105 between the water absorbent pad 2 and the second support portion 104, the first filtering portion 301 covers the water absorbent pad 2, the mounting portion 303 is pressed on the second support portion 104 by the film pressing member 4, and the second filtering portion 302 is suspended on the upper side of the spacing space 105. By adopting the above technical solution, by providing the spacing space 105, the second filtering portion 302 is suspended in the spacing space 105, which can prevent the filtering efficiency of the second filtering portion 302 from being too high, and can prevent the second filtering portion 302 from being deposited with liquid and linear accumulation of colonies 8.

[0028] In a specific implementation, the width of the second filtering part 302 and the width of the spacing space 105 can be determined by testing the actual bacterial filter membrane 3 , and they only need to ensure that no linear accumulation of colonies 8 occurs at the second filtering part 302 .

[0029] In some embodiments, the tray 1 is provided with a limiting portion 106 located outside the first supporting portion 103, and the limiting portion 106 and the first supporting portion 103 constitute a mounting groove 107 for mounting the water absorbent pad 2. With the above technical solution, the limiting portion 106 is used to limit the position of the water absorbent pad 2 to prevent the water absorbent pad 2 from moving. The water absorbent pad 2 is mounted in the mounting groove 107, which has the characteristic of easy installation. As a specific example, the limiting portion 106 is annular, and the inner circumference of the limiting portion 106 cooperates with the outer circumference of the water absorbent pad 2. Obviously, the above-mentioned mounting groove 107 is a preferred mounting structure for the water absorbent pad 2. In specific implementation, other structures capable of mounting the water absorbent pad 2 may also be adopted on the tray 1.

[0030] As a specific example, there is a gap between the upper end of the limiting portion 106 and the bacterial filter membrane 3, that is, the upper end of the limiting portion 106 is set lower than the upper surface of the absorbent pad 2, which can prevent the limiting portion 106 from having an adverse effect on the filtration efficiency of the second filtration portion 302 and prevent the limiting portion 106 from blocking the water absorption force of the absorbent pad 2.

[0031] In a specific implementation, the first filtering part 301, the second filtering part 302 and the installation part 303 are connected in sequence. In a specific implementation, the bacteria filter membrane 3 is formed by connecting the first filtering part 301, the second filtering part 302 and the installation part 303 in sequence. Figure 5 As shown, the circular portion on the bacteria filter membrane 3 surrounded by the first dotted line 304 is the first filtering portion 301, the annular portion on the bacteria filter membrane 3 between the first dotted line 304 and the second dotted line 305 is the second filtering portion 302, and the annular portion on the bacteria filter membrane 3 outside the second dotted line 305 is the installation portion 303, wherein the first dotted line 304 and the second dotted line 305 are virtual lines, which are only used to better describe the first filtering portion 301, the second filtering portion 302 and the installation portion 303.

[0032] In some embodiments, the film pressing member 4 is provided with an annular film pressing portion 401 for pressing the installation portion 303 downwards. The annular film pressing portion 401 presses the bacterial filter membrane 3 and can also prevent the sample liquid on the second filtering portion 302 from leaking outwards. It can prevent the sample liquid from leaking outwards during spreading or shaking the sample liquid. In a specific implementation, the inner circumference of the annular film pressing portion 401 surrounds the outer periphery of the second filtering portion 302.

[0033] In some embodiments, the tray 1 includes a tray bottom wall 101 and a tray side wall 102 extending upward from the edge of the tray bottom wall 101. The tray side wall 102 and the tray bottom wall 101 form a groove with an open upper side, which can prevent liquid leakage.

[0034] As a specific example, a first annular protrusion protruding upward is provided at the edge of the tray bottom wall 101, and a second annular protrusion protruding upward is also provided on the tray bottom wall 101. The first annular protrusion surrounds the periphery of the second annular protrusion at intervals, and the tray side wall 102 surrounds the periphery of the first annular protrusion. The first annular protrusion is the second supporting portion 104, and the second annular protrusion is the limiting portion 106.

[0035] As a specific example, in order to maintain the flatness of the bacterial filter membrane, the upper end surface of the second support portion 104 is a horizontally set first annular plane, the lower end surface of the film pressing member 4 is a horizontally set second annular plane, and the installation portion 303 is clamped between the first annular plane and the second annular plane.

[0036] In some embodiments, the film pressing member 4 is detachably connected to the tray 1. The film pressing member 4 can be disassembled and assembled to achieve the compression and loosening of the bacterial filter membrane 3, which is easy to implement and easy to operate. In specific implementation, the detachable connection can be, but is not limited to, a snap-on connection or a threaded connection.

[0037] As a preferred example, the film pressing member 4 and the tray side wall 102 can be connected by threaded connection. During the experiment, the film pressing member 4 can be loosened by rotating the film pressing member 4, which is easy to operate.

[0038] As a specific example, the film pressing member 4 is an annular member, and the lower end of the film pressing member 4 constitutes an annular film pressing portion 401. More specifically, the film pressing member 4 includes a connecting section 402 and an operating section 403 located on the upper side of the connecting section 402. The outer peripheral surface of the connecting section 402 is provided with an external thread, and the inner peripheral surface of the tray side wall 102 is provided with an internal thread. The external thread and the internal thread cooperate to thread the film pressing member 4 and the tray side wall 102 together. The lower end of the connecting section 402 is an annular film pressing portion 401 for pressing the installation part 303 of the bacterial filter membrane 3. The operating section 403 extends upward from the tray 1. The operating section 403 is used for the operator to operate, so that the operator can conveniently rotate the film pressing member 4, and the outer diameter of the operating section 403 can be set larger than the outer diameter of the connecting section 402.

[0039] In some embodiments, the tray 1 and the film pressing member 4 are connected to form a cavity with an open upper side, and the bacteria collector further includes a cover 5 for covering the open cavity. On the one hand, the cover 5 can prevent the bacteria filter membrane from being contaminated during transportation or experiment, and on the other hand, the cover 5 can prevent the sample liquid from leaking during the process of shaking the sample liquid. As a preferred example, the cover 5 includes a top wall of the cover 5 and a side wall of the cover 5 extending downward from the edge of the top wall of the cover 5.

[0040] In a specific implementation, both the absorbent pad 2 and the bacterial filter membrane 3 can adopt a circular structure, the diameter of the bacterial filter membrane 3 is larger than the diameter of the absorbent pad 2, and the diameter of the absorbent pad 2 is consistent with the inner diameter of the first annular portion. In a specific implementation, the bacterial filter membrane 3 is provided with filter holes for liquid to pass through and can block bacteria. The filter membrane for filtering bacteria in the prior art can be referred to, and the products sold on the market can be directly purchased. The absorbent pad 2 can be made of absorbent material, such as absorbent paper. The tray 1 and the film pressing piece 4 can be made of plastic. For example, in order to facilitate observation, the tray 1 and the film pressing piece 4 are supported by transparent plastic.

[0041] The present invention also proposes an experimental method, using any of the above-mentioned bacteria collectors, comprising the following steps: Add an appropriate amount of sample liquid to the first filtering part 301 and the second filtering part 302 of the bacterial filter membrane 3, and spread or shake the sample liquid; After the water in the sample liquid on the bacterial filter membrane 3 is absorbed and filtered, Figure 6 As shown, the bacteria filter membrane 3 is taken out and attached to the surface of the agar culture medium 7 for cultivation; After cultivation, Figure 5 As shown, the colonies 8 grown on the bacteria filter membrane 3 are observed and identified or the colonies 8 grown on the bacteria filter membrane 3 are counted.

[0042] In specific operation, the surface of the bacteria filter membrane 3 with bacteria faces away from the surface of the agar medium 7, and the agar medium 7 is usually contained in a culture dish 6. After the bacteria filter membrane 3 is attached to the surface of the agar medium 7, it is usually cultured in an incubator. The amount of the appropriate sample solution can be 1 ml, and the amount of the sample solution can also be adjusted according to the test needs.

[0043] The above experimental method has low requirements on instruments, consumables and sample size, and has the characteristics of cost saving, time saving, easy implementation and easy operation.

[0044] The above embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or changes made by those skilled in the art on the basis of the present invention are all within the protection scope of the present invention. In the description of this specification, the description of reference terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics of the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

Claims

1. A bacteria collector, characterized in that: It includes a tray, a film pressing piece, a water-absorbing pad and a bacterial filter membrane, wherein the bacterial filter membrane includes a first filtering part, a second filtering part surrounding the first filtering part and a mounting part surrounding the second filtering part, the film pressing piece can be loosely connected to the tray, the film pressing piece presses the mounting part onto the tray, the water-absorbing pad is placed on the lower side of the first filtering part, the water-absorbing pad can naturally absorb moisture on the first filtering part and the second filtering part, and the second filtering part is suspended in the air, and when the film pressing piece is loosened, the bacterial filter membrane can be taken out from the tray.

2. The bacteria collector according to claim 1, characterized in that: The tray is provided with a first supporting portion and a second supporting portion which is spaced apart and surrounds the first supporting portion. The water absorbent pad is supported on the first supporting portion. There is a spacing space between the water absorbent pad and the second supporting portion. The first filtering portion covers the water absorbent pad. The mounting portion is pressed onto the second supporting portion by the film pressing member. The second filtering portion is suspended on the upper side of the spacing space.

3. The bacteria collector according to claim 2, characterized in that: A limiting portion is disposed on the periphery of the first supporting portion, and the limiting portion and the first supporting portion constitute a mounting groove for mounting the water absorbent pad.

4. The bacteria collector according to claim 3, characterized in that: There is a gap between the upper end of the limiting portion and the bacteria filtering membrane.

5. The bacteria collector according to claim 1, characterized in that: The first filtering part, the second filtering part and the mounting part are connected in sequence.

6. The bacteria collector according to claim 1, characterized in that: The film pressing member is provided with an annular film pressing portion for pressing the installation part downwards.

7. The bacteria collector according to claim 1, characterized in that: The film pressing member is detachably connected to the tray.

8. The bacteria collector according to claim 1, characterized in that: The tray and the film pressing member are connected to form a cavity with an open upper side, and the bacteria collector also includes a cover for covering the open cavity.

9. The bacteria collector according to claim 1, characterized in that: The tray comprises a tray bottom wall and a tray side wall extending upward from an edge of the tray bottom wall.

10. An experimental method, characterized in that: The bacteria collector according to any one of claims 1 to 9 comprises the following steps: Add the sample liquid onto the bacterial filter membrane, and spread or shake the sample liquid; After the water in the sample liquid on the bacterial filter membrane is filtered out, the bacterial filter membrane is taken out and attached to the surface of the agar culture medium for cultivation; After the culturing, the colonies grown on the bacteria filter membrane are observed and identified or the colonies grown on the bacteria filter membrane are counted.

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