CN112322468A - Unidirectional negative pressure adsorption sampling and filtering device and method - Google Patents

Abstract

The invention provides a unidirectional negative pressure adsorption sampling and filtering device and a method, the device comprises a liquid taking pipe, wherein the liquid inlet end of the liquid taking pipe is provided with an oblique puncture hole, and the liquid outlet end of the liquid taking pipe is connected with a one-way valve; the liquid inlet end of the filter is connected with the one-way valve, and the liquid outlet end of the filter is connected with the stop valve; the liquid inlet end of the negative pressure metering bottle is connected with the stop valve through a connecting pipe; the liquid outlet end of the vacuum pump is connected with a negative pressure vacuum pump through an air duct; a filter cavity is arranged in the filter, and a filter medium is filled in the filter cavity. The device simplifies the operation process and improves the operation safety. The method adopts a microporous filter membrane as a filter medium, and comprises the following specific operation processes: assembling instruments, sterilizing, aseptically puncturing and draining, controlling negative pressure flow, quantitatively adsorbing and filtering, preparing a sample, storing, transporting, transferring a filter membrane in a clean area, and transferring to biochemical culture. The microporous filter membrane sample is prepared by directly carrying out water sample collection and adsorption on a water quality sampling site, so that the purpose of preparing the sample in real time, conveniently, quickly and pollution-free manner is realized.

Description

Unidirectional negative pressure adsorption sampling and filtering device and method

Technical Field

The invention belongs to the technical field of biological and chemical filtration sample preparation, and particularly relates to a unidirectional negative pressure adsorption sampling and filtering device and method.

Background

The preparation method is commonly used for filtering and preparing a prepared reagent, a standard solution and a liquid sample in the field of daily biochemical analysis so as to achieve the purposes of impurity removal, homogenization, purification, sterilization and the like. Removing impurities refers to removing larger particles, crystals, jellies, floccules and the like in the solution by filtration; homogenization refers to the separation of dispersion particles in suspension and emulsion systems by filtration, the reduction of the size of the dispersion and the improvement of the distribution uniformity of the dispersion; the purification means that tiny particles, plankton, mineral rocks, heavy metal ions and the like are removed through filtration by a filter membrane; the sterilization is to utilize the bacteria filtering characteristic of the nanometer microporous filter membrane to prevent the microorganisms from permeating into the filtrate interface.

At present, the solvent filter that chemistry experiment room and analysis laboratory are commonly used divide into organic and inorganic two kinds according to the filter membrane material, and the material is chooseed for use full glassware, and volume mass is great, and experimental operation process is often breakable, and belongs to the forward open-type and filters, and experimental operation personnel need empty the transfer solution, have great safe operation risk, and be unfavorable for operations such as sealing, aseptic.

In addition, the drinking water is polluted by microorganisms such as pseudomonas aeruginosa and the like, so that the drinking water quality safety is affected, and therefore, the drinking water quality is required to be safely detected.

In the conventional method for detecting and preparing the sample, a container is generally adopted to collect the sample of the aqueous solution on the spot, the collected sample is taken back to a laboratory, and sterile filtration operation is carried out on a 100-grade clean workbench. However, the filtering devices currently used are bulky and lack a suitable sterilizing device. And because the collection of quality of water sample and preparation appearance carry out stage by stage for the inspection time cycle is prolonged naturally, increases cross contamination risk easily, and the process operations such as disinfection, sample, transfer, filtration are loaded down with trivial details meticulous, and the requirement to inspection personnel is high, and working strength is big, has delayed work efficiency.

In the traditional method for preparing the sample, the operation processes of sampling, transferring and filter membrane preparation are longer, the requirements on clean environment and space are more spacious, a collection container needs to be thoroughly sterilized, otherwise, target microorganisms are easily influenced by a water storage container, a sampling environment, transportation conditions and the like, and uncertainty of secondary pollution is generated, such as contact of transportation and storage materials, outdoor air, media for multiple times of transferring and the like. Therefore, on the premise of no significant influence, a new sampling device needs to be developed to simplify the water quality sample preparation process and improve the work effect.

Disclosure of Invention

In order to solve the above problems, the present invention provides a unidirectional negative pressure adsorption sampling filtration device, which reduces the complicated operation process of liquid transfer filtration by synchronous operation of adsorption filtration, avoids the danger of solution filtration operation such as easy volatilization, easy corrosion and easy pollution, and improves the safety protection performance of experimental filtration operation.

The invention also aims to provide an aseptic operation method for preparing a microbial filter membrane sample in a minimally invasive manner, which adopts a microporous filter membrane as a filter medium, can complete the characteristic functions of minimally invasive puncture, unidirectional stop, reverse extract, negative pressure filtration, strain adsorption, filtrate metering, negative pressure adsorption, high temperature resistance sterilization and the like by adopting a unidirectional negative pressure adsorption sampling and filtering device, directly performs adsorption on a water quality sampling site to prepare the microporous filter membrane sample of a microbial target bacterium, completes water sample collection and filter membrane filtration operation at one time, and realizes the purpose of preparing the sample in real time, conveniently, quickly and pollution-free manner.

In order to achieve the above object, the technical solution of the present invention is as follows.

A unidirectional negative pressure adsorption sampling filter device, comprising:

the liquid inlet end of the liquid taking pipe is provided with an oblique puncture hole, and the liquid outlet end of the liquid taking pipe is connected with a one-way valve;

the liquid inlet end of the filter is connected with the one-way valve, and the liquid outlet end of the filter is connected with a stop valve;

the liquid inlet end of the negative pressure metering bottle is connected with the stop valve through a connecting pipe; the liquid outlet end of the vacuum pump is connected with a negative pressure vacuum pump through an air duct;

a filter cavity is arranged in the filter, and a filter medium is filled in the filter cavity.

Further, protective films are arranged on the side edges of the filter cavity close to the liquid inlet and the liquid outlet; the filter medium is any one or more of sand core, filter paper, active carbon, diatomite and anhydrous sodium sulfate.

Furthermore, a protective film is arranged on one side of the filter cavity close to the liquid outlet, and the filter medium is a microporous filter membrane and is used for adsorbing a microorganism sample; the microporous filter membrane is a 0.45 mu m filter membrane.

Further, the liquid taking tube is a minimally invasive puncture tube; a pipe head sterile protective cover is sleeved on the pipe head of the liquid taking pipe; the length of the liquid taking pipe is 5-20 cm.

Further, the check valve includes:

a one-way cut-off cavity is arranged in the communicating pipe;

the movable stopping component is arranged in the one-way stopping cavity; and the movable stopping component and the one-way stopping cavity are combined to form a channel for liquid to pass through along with the liquid flow.

Still further, the movable cutoff member includes:

the stopping block is arranged at the liquid inlet end of the one-way stopping cavity; one side of the stopping block is provided with an arc-shaped sealing part, and the other side of the stopping block is connected with a limiting slide rod;

the blocking groove body is arranged at the liquid outlet end of the one-way stopping cavity; a return spring is arranged in the blocking groove body, and one end of the limiting sliding rod penetrates through the return spring and penetrates out of the blocking groove body;

the blocking groove body is fixedly connected with the liquid outlet end of the one-way stopping cavity through a plurality of fixing blocks.

Further, the outer diameter of the arc-shaped sealing part is larger than the inner diameter of the communicating pipe; one side of the arc-shaped sealing part is abutted against the inner wall of the one-way stopping cavity.

Further, the filter comprises a first filter and a second filter, and the first filter is connected with the second filter in a sealing and detachable mode;

the first filter and the second filter combine to form a filter cavity for containing the filter media; and a sealing ring is arranged at the outer edge of the filter cavity.

Further, a sealing head is arranged on the negative pressure metering bottle, and a liquid level metering pipe is arranged in the negative pressure metering bottle; one end of the sealing head is abutted against one end of the liquid level metering pipe, and the negative pressure metering bottle is communicated with the liquid level metering pipe;

the liquid inlet joint and the exhaust joint are arranged on the sealing head, one end of the liquid inlet joint, which is positioned in the sealing head, extends into the liquid level metering pipe, and the other end of the liquid inlet joint is hermetically and detachably connected with the connecting pipe;

the one end that the exhaust joint is located sealed head set up in the upside of liquid level metering tube, the other end with the air duct is sealed can dismantle the connection.

The invention also provides an aseptic operation method for preparing the microbial filter membrane sample by adopting the unidirectional negative pressure adsorption sampling and filtering device in a minimally invasive manner, which comprises the following steps:

s1, assembling the liquid taking pipe, the one-way valve, the filter, the stop valve and the negative pressure measuring bottle and then sterilizing;

s2, connecting the negative pressure measuring bottle with a negative pressure vacuum pump, puncturing the beveled end of the liquid taking pipe into a water sample, opening a stop valve, starting the negative pressure vacuum pump, enabling the water sample to enter the negative pressure measuring bottle through a filter, and adsorbing microorganisms in the water sample on a filter medium for preparing a microporous filter membrane sample, wherein the filter medium is a microporous filter membrane;

after adsorption sampling and filtering, closing the stop valve after the filtrate meets a certain capacity;

s3, placing the one-way valve, the filter and the stop valve in an aseptic storage box for sample preparation, storage and transportation, and then transferring the microporous filter membrane sample in a clean area;

s4, transferring the microorganisms on the microporous filter membrane sample into a culture dish for biochemical culture for water quality microorganism detection.

The invention has the beneficial effects that:

1. the device reduces the complex operation process of liquid transfer filtration through the synchronous operation of adsorption filtration, avoids the danger of solution filtration operation such as easy volatilization, easy corrosion, easy pollution and the like, and improves the safety protection performance of experimental filtration operation.

2. The device is formed by sequentially connecting three units of sampling, filtering and negative pressure, wherein the sampling unit mainly comprises a liquid taking pipe and a one-way valve, liquid is sucked through the liquid taking pipe, and the functions of one-way stopping and reverse liquid extracting are realized. The filter unit comprises a filter and a stop valve, wherein a filter medium and a protective film are additionally arranged in a filter cavity of the filter, and when the filter medium adopts a microporous filter membrane, the filter unit can be used for realizing negative pressure filtration and strain adsorption functions. The negative pressure unit comprises a negative pressure metering bottle, negative pressure is kept in the negative pressure metering bottle through a negative pressure vacuum pump, and then filtrate is quantitatively adsorbed in the negative pressure metering bottle, so that the functions of filtrate metering and negative pressure adsorption are realized. The whole device is light in weight, easy to carry, pressure-resistant, good in connection air tightness, adjustable in negative pressure, and the negative pressure is not lower than 0.04 MPa.

3. The device disclosed by the invention combines the negative pressure adsorption liquid taking of the static liquid level with the one-way multi-medium adsorption filtration, so that the inspection timeliness and the working efficiency of a laboratory can be improved, the safety risk of biochemical operation can be prevented, the open environmental pollution is avoided, the working intensity of conventional operation in the personnel detection process is reduced, and the complicated manual operation problems in liquid pouring, adsorption transfer and quantitative filtration in the laboratory detection process are solved.

4. The method adopts a microporous filter membrane as a filter medium and a minimally invasive puncture tube as a sampling tube. The specific operation process comprises the following steps: assembling instruments, sterilizing, aseptically puncturing and draining, controlling negative pressure flow, quantitatively adsorbing and filtering, preparing samples, storing and transporting, transferring a clean area filter membrane, and transferring to biochemical culture. The method simplifies the sample preparation operation flow, can complete the characteristic functions of minimally invasive puncture, unidirectional cut-off, reverse extraction, negative pressure filtration, strain adsorption, filtrate metering, negative pressure adsorption, high temperature resistance sterilization and the like, directly performs adsorption preparation on a microporous filter membrane sample of microorganism target bacteria on a water quality sampling site, completes water sample collection and filter membrane filtration operation at one time, and realizes the purpose of preparing samples in real time, conveniently, quickly and without pollution; the cross contamination of water sample collection and on-site preparation is avoided, the operation process is simplified, and the working efficiency is improved.

Drawings

Fig. 1 is a schematic structural diagram of a unidirectional negative pressure adsorption sampling and filtering device according to an embodiment of the present invention.

Fig. 2 is a schematic structural view of a portion a in fig. 1.

FIG. 3 is a schematic view of the configuration of the fluid-withdrawal tube of FIG. 1.

Fig. 4 is a schematic structural view of the check valve of fig. 1.

Fig. 5 is a schematic cross-sectional view of the check valve of fig. 4.

Fig. 6 is a schematic view of the check valve in fig. 4 in use.

Fig. 7 is a schematic cross-sectional view of the filter of fig. 1.

FIG. 8 is a schematic view of the negative pressure metering bottle of FIG. 1.

Fig. 9 is a schematic structural view of a unidirectional negative pressure adsorption sampling filter device according to another embodiment of the present invention.

In the figure, 1, a liquid taking tube; 11. a puncture hole is inclined; 12. an oblique joint; 13. a tube head sterile protective cover;

2. a one-way valve; 21. a communicating pipe; 211. a one-way shut-off chamber; 22. a movable cut-off member; 221. a stop block; 222. an arc-shaped sealing part; 223. a limiting slide bar; 224. a blocking groove body; 225. a return spring; 226. a fixed block;

3. a filter; 31. a filter chamber; 32. a filter medium; 33. a protective film; 34. a first filter; 35. a second filter; 36. a seal ring; 4. a stop valve;

5. a negative pressure metering bottle; 51. a sealing head; 52. a liquid inlet joint; 53. an exhaust joint; 54. a liquid level metering tube; 541. a pipe orifice limiting part; 55. a bottle mouth clamping part; 6. a connecting pipe; 7. an air duct; 8. a negative pressure vacuum pump.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Fig. 1 is a schematic structural diagram of a unidirectional negative pressure adsorption sampling and filtering device according to an embodiment of the present invention. The device is mainly applied to the operation of biochemical filtration and liquid extraction in a laboratory. The device comprises a liquid taking pipe 1, a filter 3 and a negative pressure measuring bottle 5.

Referring to fig. 1 to 3, the liquid inlet end of the liquid taking tube 1 is provided with an inclined puncture 11, and the liquid outlet end thereof is connected with a one-way valve 2. Liquid is sucked through the liquid taking pipe, and the functions of unidirectional stopping and reverse liquid extracting are realized.

Wherein, the pipe head of the liquid taking pipe 1 can be made of different corrosion-resistant materials and pipe diameters. For example, the material of the head of the liquid extraction tube is suitable for the liquid, and the length of the liquid extraction tube 1 can be determined by the medium immersed in the liquid, and is about 5-20 cm. The size of the outer diameter and the inner diameter of the liquid taking pipe 1 is about 2-8 mm; specifically, the inner diameter of the liquid taking pipe 1 is sequentially reduced from top to bottom, and the inner diameter of the beveled end of the liquid taking pipe 1 is 2-5 mm.

An inclined joint 12 is arranged at the liquid outlet end of the liquid taking pipe 1, and the inclined joint 12 is hermetically and detachably connected with the liquid inlet end of the one-way valve 2. Of course, the upper end dimension of the diagonal joint 12 is greater than the lower end dimension, e.g., the upper inner diameter dimension of the diagonal joint 12 is about 12.6mm and the lower inner diameter dimension is about 12.2 mm. Of course, the lower end of the check valve 2 can be sleeved with a sealing ring, the upper outer diameter of the sealing ring is about 12.6mm, and the lower outer diameter of the sealing ring is about 12.2 mm. The lower end of the check valve 2 is pressed in the oblique joint 12, and the sealing ring is tightly attached to the inner wall of the oblique joint 12, so that the sealing tightness between the oblique joint 12 and the check valve 2 can be improved. Of course, an engaging member may be added to the connection end between the diagonal joint 12 and the check valve 2 to further improve the fastening of the connection.

Referring to fig. 1 and 7, the liquid inlet end of the filter 3 is connected to the one-way valve 2, and the liquid outlet end of the filter 3 is connected to the stop valve 4; the liquid inlet end of the negative pressure measuring bottle 5 is connected with the stop valve 4 through a connecting pipe 6, and the liquid outlet end of the negative pressure measuring bottle 5 is connected with a negative pressure vacuum pump 8 through an air duct 7.

For example, the upper inner diameter of the liquid outlet end of the one-way valve 2 is about 11.6mm, and the lower inner diameter is about 10.6 mm; the upper outer diameter of the liquid inlet end of the filter 3 is about 11.6mm, the lower outer diameter is about 10.6mm, and the inner pore diameter is about phi 5 mm; the liquid inlet end of the filter 3 can be tightly inserted on the liquid outlet end of the one-way valve 2. The upper outer diameter of the liquid outlet end of the filter 3 is about 10.6mm, the lower outer diameter is about 11.6mm, and the inner hole diameter is about phi 4 mm; the upper inner diameter of the liquid inlet end of the stop valve 4 is about 10.6mm, the lower inner diameter is about 11.6mm, and the inner aperture is about phi 4 mm; the liquid outlet end of the filter 3 can be tightly inserted and connected with the liquid inlet end of the stop valve 4.

Wherein, be provided with filter chamber 31 in the filter 3, filter chamber 31 is filled with filter medium 32. When the device is applied to the filtration operation of a chemical laboratory or an analysis laboratory, protective films 33 are arranged on the side edges of the filter cavity 31 close to the liquid inlet and the liquid outlet; the filter medium 32 is any one or more of sand core, filter paper, activated carbon, diatomite and anhydrous sodium sulfate. Different filter media may be selected for different filtered liquids and filtering purposes.

Of course, the filter 3 is detachable so as to facilitate replacement of the multimedia filtering material. Specifically, the filter 3 includes a first filter 34 and a second filter 35, and the first filter 34 is detachably connected to the second filter 35 in a sealing manner; first filter 34 in combination with second filter 35 form filter cavity 31 for receiving filter media 32; the outer edge of filter chamber 31 is provided with a sealing ring 36.

For example, the first filter and the second filter are fastened by screw threads, and a communicating cavity, namely the filter chamber 31, is formed between the first filter and the second filter. After placement of the filter media and protective membrane, the volume of the cavity can be reduced by tightening the first filter and the second filter, thereby compressing the protective membrane against the filter media 32.

In this embodiment, the puncture liquid-taking operation is facilitated through the oblique puncture port 11. Because the length of liquid-taking pipe is longer relatively, can directly pierce liquid-taking pipe 1 and wait to get among the liquid medium, saved the operation process that the laboratory technician carried, shifted and emptyd. The operation of sucking and filtering liquid under negative pressure can be real-time, convenient, fast and pollution-free. Certainly, the setting of the one-way valve 2 can realize the functions of one-way stopping and reverse liquid extracting, and the liquid is prevented from flowing back reversely to fall into the sampled liquid in the negative pressure sampling process, so that the secondary pollution of the sampled liquid is avoided.

The device is through getting liquid and the combination of one-way many media adsorption filtration with the negative pressure adsorption of static liquid level, can improve the inspection ageing and the work efficiency in laboratory, can prevent biochemical operation safety risk, avoids open-type environmental pollution, reduces the working strength of conventional operation among the personnel's the testing process, and has solved in the laboratory testing process and has emptyd liquid, adsorb the manual operation problem of numerous and diverse among the transfer, many media filtration.

Referring to fig. 4 to 6, the check valve 2 includes a communication pipe 21 and a movable shut-off member 22.

A one-way cut-off cavity 211 is arranged in the communicating pipe 21; for example, the communication pipe 21 includes a first connector 201 and a second connector 202, an upper end of the first connector 201 abuts against an inner wall of the second connector 202, and the first connector 201 is screwed with the second connector 202. Of course, a sealing collar may be further disposed at an end of the first connecting member 201 to improve the sealing and tightness between the first connecting member 201 and the second connecting member 202. Thereby forming a passage for the liquid to pass between the first connector 201 and the second connector 202.

The movable cut-off part 22 is arranged in the one-way cut-off cavity 211; and as the liquid flows, the movable cutoff member 22 forms a passage through which the liquid passes in combination with the unidirectional cutoff cavity 211.

Specifically, the movable shut-off member 22 includes a shut-off block 221 and a block groove 224.

The stopping block 221 is arranged at the liquid inlet end of the one-way stopping cavity 211; and one side of the stop block 221 is provided with an arc-shaped sealing part 222, and the other side is connected with a limit slide bar 223. Here, one side of the one-way cutoff cavity 211 close to the liquid inlet is provided with an arc-shaped inner cavity wall, the arc-shaped sealing part of the cutoff block is abutted against the arc-shaped inner cavity wall, and the one-way cutoff cavity can be sealed against the liquid inlet.

The blocking groove body 224 is arranged at the liquid outlet end of the one-way stopping cavity 211; a return spring 225 is arranged in the blocking groove body 224, and one end of the limiting slide rod 223 penetrates through the return spring 225 and penetrates out of the blocking groove body 224. Here, the blocking groove 224 and the stopping block 221 are both provided with accommodating grooves, and form an accommodating cavity in combination, and the return spring 225 is disposed in the accommodating cavity. A through groove is formed in the blocking groove body 224, one end of the limiting slide rod 223 is fixedly arranged in the accommodating groove of the stopping block 221, and the other end of the limiting slide rod passes through the through groove and can move along the through groove.

In the use, when being in the ordinary pressure environment in the cavity, the arc sealing part butt of cutting off the piece is on the one-way arc inner chamber wall that cuts off the chamber, and the spring is in the state of compressing tightly this moment for it keeps the butt on the one-way inlet that cuts off the chamber to cut off the piece.

When being in the negative pressure environment in the cavity, receive the negative pressure effect and open the inlet on the one hand by the piece, on the other hand because the water sample draws liquid upwards and orders about to stop the piece butt on blockking the cell body, and then opens one-way chamber that stops, forms the passageway that liquid passes through.

When liquid passes through the one-way stop cavity, the negative pressure applied to the stop block is reduced along with the reduction of the negative pressure, and when the negative pressure is smaller than the reset acting force of the spring, the stop block moves downwards and abuts against the arc-shaped inner cavity wall of the one-way stop cavity, and the spring is in a pressing state at the moment and closes the liquid inlet.

The blocking groove body 224 is fixedly connected with the liquid outlet end of the one-way stopping cavity 211 through a plurality of fixing blocks 226. Here, because the fixed block makes and blocks that to form a plurality of liquid holes between the inner wall that the cell body and one-way end chamber are close to the liquid outlet, when the fixed cell body that blocks, the liquid of being convenient for passes through.

The outer diameter of the arc seal portion 222 is larger than the inner diameter of the communication pipe 21; one side of the arc-shaped sealing part 222 abuts against the inner wall of the one-way stopping cavity 211 so as to seal the liquid inlet of the one-way stopping cavity.

Referring to fig. 1 to fig. 2 and fig. 8 again, the vacuum metering bottle 5 is provided with a sealing head 51, and the sealing head 51 is detachably connected to the vacuum metering bottle 5 in a sealing manner; for example, the sealing head 51 is connected to the negative pressure measuring bottle 5 by a screw seal.

A liquid level metering pipe 54 is arranged in the negative pressure metering bottle 5; one end of the sealing head 51 is abutted against one end of the liquid level measuring pipe 54, and the negative pressure measuring bottle 5 is communicated with the liquid level measuring pipe 54; the sealing head 51 is provided with a liquid inlet joint 52 and an exhaust joint 53, one end of the liquid inlet joint 52 positioned in the sealing head extends into the liquid level metering pipe 54, and the other end is in sealing detachable connection with the connecting pipe 6; one end of the exhaust joint 53 in the sealing head is arranged on the upper side of the liquid level metering pipe 54, and the other end is connected with the air duct 7 in a sealing and detachable manner.

In this embodiment, be provided with the liquid level scale on the outer wall of liquid level measurement pipe, conveniently carry out negative pressure flow control and quantitative adsorption filtration. In order to improve the negative pressure filtering effect, please refer to fig. 2, a bottle opening clamping portion 55 is disposed on a bottle opening of the negative pressure measuring bottle 5, a pipe opening limiting portion 541 is disposed on a pipe opening of the liquid level measuring tube 54, the liquid level measuring tube 54 is accommodated in the negative pressure measuring bottle 5, at this time, the pipe opening limiting portion 541 is clamped on the bottle opening clamping portion 55, so that a spaced inner cavity is disposed between the liquid level measuring tube 54 and the negative pressure measuring bottle 5, and the spaced inner cavity is communicated with the inner cavity of the liquid level measuring tube 54 due to the communicating hole disposed between the liquid level measuring tube 54 and the bottle opening clamping portion. Of course, a plurality of vent holes may be provided at the mouth of the level gauge tube 54, such that the compartment cavity is further communicated with the level gauge tube 54 through the plurality of vent holes. The negative pressure environment is conveniently formed in the inner cavity of the separation cavity.

The negative pressure measuring bottle 5 provided by the embodiment is a positive negative pressure bottle, the liquid inlet joint 52 and the air outlet joint 53 are both positioned at the top of the negative pressure measuring bottle 5, and the bottle mouth is upward; the negative pressure environment is conveniently formed.

Wherein, the tip that the inlet joint 52 is located negative pressure metering bottle extends to in the mouth of pipe of liquid level metering pipe 54, and exhaust joint 53 is located the tip of negative pressure metering bottle and is located the mouth of pipe upside of liquid level metering pipe 54, when carrying out the imbibition through the inlet joint from this, with carry out the negative pressure through exhaust joint and breathe in each other not influence, can avoid when the negative pressure is breathed in through the inlet joint entering liquid level metering pipe liquid along with the negative pressure breathe in and be sucked to the negative pressure vacuum pump in. Of course, the inlet joint 52 and the outlet joint 53 are provided with control valves. Negative pressure environment can be formed on the inner cavity of the negative pressure measuring bottle 5 through the negative pressure vacuum pump 8, and the whole negative pressure environment of the device is kept, so that sample liquid can be quickly and conveniently adsorbed and filtered. The exhaust joint 53 is connected with a negative pressure vacuum pump 8 through an air duct 7 for forming a negative pressure environment, and the inlet joint 52 is connected with the stop valve 4 through a connecting pipe 6 for sampling and filtering, and making the sampling liquid flow into a liquid level metering pipe 54, and realizing quantitative sampling. By providing the liquid level measuring tube 54 in the negative pressure measuring bottle 5, quantitative measurement can be performed in the sampling process, and quantitative measurement and sampling of filtrate can be realized. The air exhaust end of the negative pressure vacuum pump 8 is connected with a pressure gauge, and negative pressure is adjusted through the pressure gauge so as to form a reasonable negative pressure sampling environment.

Example 2

Referring to fig. 9, a schematic structural diagram of a unidirectional negative pressure adsorption sampling and filtering device according to another embodiment of the present invention is shown, the device includes a liquid taking tube 1, a filter 3 and a negative pressure measuring bottle 5. The structure of the device is substantially the same as that of embodiment 1, except that,

negative pressure metering bottle 5 is including feed liquor opening and negative pressure gas vent, and the feed liquor opening sets up in negative pressure metering bottle 5's bottom, and the negative pressure gas vent sets up on the lateral wall at negative pressure metering bottle 5's top, and the feed liquor opening passes through connecting pipe 6 to be connected with stop valve 4, and the negative pressure gas vent passes through air duct 7 to be connected with negative pressure vacuum pump 8 to can form the negative pressure environment to the device, so that filter appearance liquid fast conveniently.

In this embodiment, the negative pressure measuring bottle 5 is a reverse negative pressure bottle having a downward opening. The liquid inlet joint 52 is arranged on the liquid inlet opening, the exhaust joint is arranged on the negative pressure exhaust port, the liquid inlet joint 52 and the exhaust joint 53 are both communicated with the inner cavity of the negative pressure metering bottle 5, and of course, the liquid inlet joint 52 and the exhaust joint 53 are both provided with control valves. The outer wall of the negative pressure measuring bottle 5 is provided with liquid level scales, so that negative pressure flow control and quantitative adsorption filtration can be conveniently carried out.

Example 3

Referring to fig. 1, another embodiment of the present invention provides a unidirectional negative pressure adsorption sampling filter device, which has a structure substantially the same as that of example 1, except that,

the device is mainly applied to the aseptic preparation of the microorganism samples. Wherein the liquid taking tube 1 is a minimally invasive puncture tube; a tube head sterile protective cover 13 is sleeved on the tube head of the liquid taking tube 1; used for realizing aseptic protection to the tube head of the liquid taking tube. The length of the liquid taking pipe 1 is 15-20 cm.

One side of the filter cavity 31 close to the liquid outlet is provided with a protective film 33, and the filter medium 32 is a microporous filter film for adsorbing a microorganism sample. Wherein the microfiltration membrane 32 is a 0.45 μm membrane.

In this embodiment, a microporous filter membrane and a protective membrane 33 are sequentially disposed in the filter chamber along the direction of liquid flow, and the microporous filter membrane is mainly used for adsorbing a microorganism sample and filtering a water sample. The protection film sets up in the one side that the filter chamber is close to the liquid outlet, can avoid negative pressure to the damage of millipore filtration membrane. For example, the protective film is a plastic film.

In the embodiment, the device mainly comprises a sampling unit, a filtering unit and a negative pressure unit, and the functions of minimally invasive puncture, unidirectional cut-off and reverse liquid extraction are realized through the sampling unit; the functions of negative pressure filtration and strain adsorption are realized through the filtration unit; the functions of filtrate metering and negative pressure adsorption are realized through the negative pressure unit.

The device mainly selects the material of light, transparent, withstand voltage deformation, corrosion-resistant, high temperature resistant, easy disinfection and ageing resistance, and the preferred selection PP (polypropylene) plastics material is moulded plastics the customization and is formed. All components for sampling and filtering are required to be connected and sealed, high-temperature sterilization resistant and difficult to age and deform, and the negative pressure component is required to be pressure-resistant, good in connection air tightness, adjustable in negative pressure and not less than 0.07 MPa.

The device is small in size, light in weight, convenient to carry indoors and outdoors, simple in connection combination and convenient to operate, can perform minimally invasive puncture, negative pressure drainage and adsorption lifting on a bottle (barrel) opening for containing liquid, greatly improves the safety and convenience of operation, and has good application value.

The device can be used for establishing an aseptic operation method for preparing a microbial filter membrane sample by a filter membrane method, and is expanded to other microbial detection application fields.

The aseptic operation method for preparing the microbial filter membrane sample by the minimally invasive method by adopting the one-way negative pressure adsorption sampling and filtering device comprises the following steps:

s1, assembling the liquid taking pipe 1, the one-way valve 2, the filter 3, the stop valve 4 and the negative pressure measuring bottle 5, and then sterilizing;

s2, connecting the negative pressure measuring bottle 5 with the negative pressure vacuum pump 8, puncturing the beveled end part of the liquid taking pipe 1 into a water sample, opening the stop valve 4, starting the negative pressure vacuum pump 8, enabling the water sample to enter the negative pressure measuring bottle 5 through the filter 3, and adsorbing microorganisms in the water sample on a filter medium 32 for preparing a microporous filter membrane sample, wherein the filter medium 32 is a microporous filter membrane;

after adsorption sampling and filtering, closing the stop valve 4 after the filtrate meets a certain capacity;

s3, placing the one-way valve 2, the filter 3 and the stop valve 4 in an aseptic storage box for sample preparation, storage and transportation, and then transferring the microporous filter membrane sample in a clean area;

s4, transferring the microorganisms on the microporous filter membrane sample into a culture dish for biochemical culture for water quality microorganism detection.

The method mainly comprises the following procedures: assembling instruments, sterilizing, aseptically puncturing and draining, controlling negative pressure flow, quantitatively adsorbing and filtering, preparing samples, storing and transporting, transferring a clean area filter membrane, and transferring to biochemical culture.

The device needs to be assembled and disinfected before detection, high-temperature disinfection is adopted for disinfection, minimally invasive surface disinfection is carried out on the surface of the barreled water, the aseptic protective cover 13 of the tube head connected to the liquid taking tube is opened, and the liquid taking tube is inserted into the barreled water to carry out adsorption sampling filtration operation. At the moment, the filtrate enters a negative pressure metering bottle, and microorganisms are adsorbed on a 0.45-micron microporous filter membrane to prepare a target bacteria adsorption filter membrane sample. The sample is transferred to an ultra-clean workbench through a sterile storage box, then is transferred through a microporous filter membrane, and is placed on a CN agar culture medium for subsequent microbiological examination procedures.

Compared with the traditional method, the method synchronously combines water sample collection and filter membrane filtration, implements a minimally invasive aseptic operation means, avoids cross contamination of water sample collection and on-site preparation, shortens the detection process, realizes the one-time preparation of the target microorganism filter membrane, then brings the target microorganism filter membrane back to a laboratory for the next biochemical culture procedure, and improves the inspection timeliness and the working efficiency. The phenomenon that in the traditional method, due to the fact that the microorganism detection sample is delayed, microorganisms can be in different survival growth curve states within a certain time period, the target microorganism survival state and the water quality instant current state are asynchronous under the objective condition of the water quality nutrient source, and unreal influence can be caused on real-time data result evaluation.

In the embodiment, the water sample in the filter cavity can only meet the growth requirement of microorganisms without forming logarithmic phase growth. Therefore, the method combines the negative pressure adsorption sampling of the static liquid level with the one-way microporous filter membrane adsorption filtration preparation sample, and can improve the inspection timeliness and the working efficiency under the outdoor environmental condition of the laboratory. The water quality microbiological test sample can be rapidly and conveniently prepared in the process of collecting the sample on site, the safety risk of biochemical operation can be prevented, and the effectiveness of a test result is ensured.

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. The utility model provides a one-way negative pressure adsorbs sample filter equipment which characterized in that includes:

the liquid inlet end of the liquid taking pipe (1) is provided with an oblique puncture opening (11), and the liquid outlet end of the liquid taking pipe is connected with a one-way valve (2);

the liquid inlet end of the filter (3) is connected with the one-way valve (2), and the liquid outlet end of the filter is connected with a stop valve (4);

the liquid inlet end of the negative pressure metering bottle (5) is connected with the stop valve (4) through a connecting pipe (6); the liquid outlet end of the vacuum pump is connected with a negative pressure vacuum pump (8) through an air duct (7);

a filtering cavity (31) is formed in the filter (3), and a filtering medium (32) is filled in the filtering cavity (31).

2. The unidirectional negative pressure adsorption sampling and filtering device of claim 1, wherein the side edges of the filter cavity (31) close to the liquid inlet and the liquid outlet are provided with protective films (33); the filter medium (32) is one or more of sand core, filter paper, active carbon, diatomite and anhydrous sodium sulfate.

3. The unidirectional negative pressure adsorption sampling and filtering device of claim 1, wherein a protective film (33) is arranged on one side of the filter cavity (31) close to the liquid outlet, and the filter medium (32) is a microporous filter film for adsorbing a microorganism sample.

4. The unidirectional negative pressure adsorption sampling and filtering device according to claim 1, wherein the liquid taking tube (1) is a minimally invasive puncture tube; a tube head sterile protective cover (13) is sleeved on the tube head of the liquid taking tube (1); the length of the liquid taking pipe (1) is 5-20 cm.

5. A one-way negative pressure adsorption sampling filtration device according to claim 1, characterized in that the one-way valve (2) comprises:

a communicating pipe (21) in which a one-way cut-off chamber (211) is provided;

the movable cut-off component (22) is arranged in the one-way cut-off cavity (211);

as the liquid flows, the movable stopping component (22) and the one-way stopping cavity (211) are combined to form a channel for the liquid to pass through.

6. A unidirectional negative pressure adsorption sampling filtration device according to claim 5, characterized in that the movable shut-off member (22) comprises:

the stopping block (221) is arranged at the liquid inlet end of the one-way stopping cavity (211); an arc-shaped sealing part (222) is arranged on one side of the stopping block (221), and a limiting slide rod (223) is connected to the other side of the stopping block;

the blocking groove body (224) is arranged at the liquid outlet end of the one-way blocking cavity (211); a return spring (225) is arranged in the blocking groove body (224), and one end of the limiting sliding rod (223) penetrates through the return spring (225) and penetrates out of the blocking groove body (224);

the blocking groove body (224) is fixedly connected with the liquid outlet end of the one-way stopping cavity (211) through a plurality of fixing blocks (226).

7. The one-way negative pressure adsorption sampling and filtering device of claim 6, wherein the outer diameter of the arc-shaped sealing part (222) is larger than the inner diameter of the communicating pipe (21); one side of the arc-shaped sealing part (222) is abutted against the inner wall of the one-way stopping cavity (211).

8. The unidirectional negative pressure adsorption sampling and filtering device of claim 1, wherein the filter (3) comprises a first filter (34) and a second filter (35), the first filter (34) is connected with the second filter (35) in a sealing and detachable way;

the first filter (34) and the second filter (35) in combination forming a filter chamber (31) for containing the filter medium (32); and a sealing ring (36) is arranged at the outer edge of the filtering cavity (31).

9. The unidirectional negative pressure adsorption sampling and filtering device of claim 1, wherein a sealing head (51) is arranged on the negative pressure metering bottle (5), and a liquid level metering pipe (54) is arranged in the negative pressure metering bottle (5); one end of the sealing head (51) is abutted against one end of the liquid level measuring pipe (54), and the negative pressure measuring bottle (5) is communicated with the liquid level measuring pipe (54);

a liquid inlet joint (52) and an exhaust joint (53) are arranged on the sealing head (51), one end of the liquid inlet joint (52) positioned in the sealing head extends into the liquid level metering pipe (54), and the other end of the liquid inlet joint is hermetically and detachably connected with the connecting pipe (6);

one end of the exhaust joint (53) in the sealing head is arranged on the upper side of the liquid level metering pipe (54), and the other end of the exhaust joint is connected with the air guide pipe (7) in a sealing and detachable mode.

10. A method of performing an aseptic procedure for the minimally invasive preparation of a sample of a microbiological filter membrane using the apparatus of claim 1, comprising the steps of:

s1, assembling the liquid taking pipe, the one-way valve, the filter, the stop valve and the negative pressure measuring bottle and then sterilizing;

s2, connecting the negative pressure measuring bottle with a negative pressure vacuum pump, puncturing the beveled end of the liquid taking pipe into a water sample, opening a stop valve, starting the negative pressure vacuum pump, enabling the water sample to enter the negative pressure measuring bottle through a filter, and adsorbing microorganisms in the water sample on a filter medium for preparing a microporous filter membrane sample, wherein the filter medium is a microporous filter membrane;

after adsorption sampling and filtering, closing the stop valve after the filtrate meets a certain capacity;

s3, placing the one-way valve, the filter and the stop valve in an aseptic storage box for sample preparation, storage and transportation, and then transferring the microporous filter membrane sample in a clean area;

s4, transferring the microorganisms on the microporous filter membrane sample into a culture dish for biochemical culture for water quality microorganism detection.

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