Air bioaerosol sampling device and sampling method thereof

Abstract

The present invention provides an air bioaerosol sampling device and a sampling method thereof in the field of bioaerosol sampling technology, comprising a polymerization reflux channel, a flow meter, a temperature control cylinder, a vacuum pump, a thermometer, an air inlet, a vaporized liquid storage bottle, a ceramic vaporization core, a condensation growth channel, a sampling bottle, a reflux liquid guide plate, a ceramic atomizing plate, an atomized liquid storage bottle, a reflux liquid collection tank, and a reflux liquid outlet. The present invention provides a ceramic vaporization core and a condensation growth channel. The ceramic vaporization core heats glycerol in the vaporized liquid storage bottle to generate hydrophilic molecules. The hydrophilic molecules entering the condensation growth channel and water vapor in the air continuously condense on the surface of the bioaerosol, causing its volume to continuously increase to form droplets. The condensation action and polymerization with the atomized droplets can cause the volume of the bioaerosol in the environmental sample to gradually increase in the sampler, effectively preventing the escape of tiny aerosols and achieving the maximum capture of bioaerosols of different particle sizes in the air.

Description

Technical Field

[0001] The present invention relates to the technical field of bioaerosol sampling, and in particular to an air bioaerosol sampling device and a sampling method thereof. Background Art

[0002] At present, for air microbial analysis, samples obtained by traditional culture-based samplers, such as the six-level Anderson sampler and Sartorius AirPortMD8 sampler, can no longer meet the research needs of metagenomic sequencing.

[0003] Large-flow membrane filter samplers and large-flow jet or centrifugal impact liquid impact samplers have been widely used as mainstream products for aerosol sample collection, such as TISCH, Qingdao Laoying 2031, SKCbiosampler, CORIOLISμ, etc. Although large-flow membrane filter samplers and large-flow jet or centrifugal impact samplers can maintain the DNA extraction volume of samples to a certain extent, it is still difficult to meet the DNA extraction volume requirements for metagenomic sequencing. This is because the large flow rate used in the sampling process can cause impact shear stress and thus damage microbial cells, and the secondary entrainment of the airflow can lead to a decrease in aerosol capture efficiency. In addition, when the cyclone sampler collects aerosol samples, it is possible that the tiny droplets entering the cyclone sampler will be evaporated and vaporized by the high-speed airflow or entrained and flowed out by the high-speed airflow, and the ideal collection effect cannot be achieved. An aerosol sampler with high capture efficiency should enable the samples obtained to meet the needs of 16SrRNA high-throughput sequencing, qPCR (quantitative polymerase chain reactions), metagenomic sequencing, culture, screening and isolation of single bacteria within a relatively short sampling time. However, the currently available aerosol sampling methods have been verified to be unable to meet these requirements.

[0004] A prior art search revealed a Chinese invention patent, CN114181815A, which discloses a high-flow ambient air bioaerosol sampling device and method. During experimental verification of this patent, the problem arose: most of the tiny droplets entering the cyclone sampler were vaporized or entrained by the high-speed airflow, preventing the droplets from forming a liquid film and washing the bioaerosols to the bottom of the cyclone sampler.

[0005] A prior art search revealed a Chinese invention patent, published under the publication number CN110387318A, which discloses a large-volume aerosol sampler suitable for air microbial analysis. However, because this patent still relies on the liquid impact principle, the high flow rate used during sampling can damage microbial cells, reducing collection efficiency. Summary of the Invention

[0006] In view of the defects in the prior art, the purpose of the present invention is to provide an air bioaerosol sampling device and a sampling method suitable for metagenomic sequencing.

[0007] According to the present invention, an air bioaerosol sampling device is provided, comprising a vacuum pump and a polymerization reflux channel, wherein the vacuum pump is connected to one end of the polymerization reflux channel;

[0008] The other end of the polymerization reflux channel is connected to a reflux liquid guide plate, and the reflux liquid guide plate is arranged in the sampling bottle;

[0009] The top of the sampling bottle is connected to one end of the condensation growth channel, the bottom of the sampling bottle is connected to the reflux liquid outlet, an atomized liquid storage bottle is provided inside the sampling bottle, and the top of the atomized liquid storage bottle is connected to a ceramic atomizing piece;

[0010] An air inlet is provided on the condensation growth channel, and the other end of the condensation growth channel is connected to a gasification liquid storage bottle, and a ceramic gasification core is provided at the bottom end of the gasification liquid storage bottle;

[0011] The reflux liquid guide plate prevents the reflux liquid flowing in the polymerization reflux channel from dripping onto the ceramic atomizing plate.

[0012] In some embodiments, it is characterized in that the upper air inlet of the vacuum pump is connected to the upper air outlet of the polymerization reflux channel.

[0013] In some embodiments, a flow meter is provided between the vacuum pump and the polymerization reflux channel.

[0014] In some embodiments, an air inlet is provided on the condensation growth channel, a lower end of the air inlet is connected to a gasification liquid storage bottle, and an upper end of the air inlet is connected to a thermometer, and the thermometer is used to measure the temperature of the air inlet.

[0015] In some embodiments, a reflux liquid collection tank is provided between the atomized liquid storage bottle and the sampling bottle;

[0016] The reflux liquid guide plate guides the reflux liquid to the reflux liquid collecting tank, and the reflux liquid outlet discharges the reflux liquid.

[0017] In some embodiments, it is characterized in that it further includes a temperature control cylinder, which is detachably arranged on the outside of the sampling bottle, and part of the pipeline of the polymerization reflux channel and part of the pipeline of the condensation growth channel extend into the interior of the temperature control cylinder.

[0018] In some embodiments, it is characterized in that the vaporized liquid storage bottle, the ceramic vaporization core, the condensation growth channel, the temperature control cylinder, the air inlet, the thermometer and the reflux liquid collection tank together constitute a downward flow vaporization and condensation system;

[0019] The atomized liquid storage bottle, the ceramic atomizing sheet, the reflux liquid guide plate, the polymerization reflux channel and the reflux liquid collecting tank together constitute an upward flow polymerization recovery system.

[0020] In some embodiments, it is characterized in that the liquid in the gasified liquid storage bottle is glycerol, and the liquid in the nebulized liquid storage bottle is PBS buffer.

[0021] An air bioaerosol sampling method, using the air bioaerosol sampling device, is characterized by comprising the following steps:

[0022] Step 1: Before sampling begins, all components except the flow meter, the temperature control cylinder, the vacuum pump, and the thermometer must be placed in an autoclave for high-temperature steam sterilization;

[0023] At the beginning of sampling, a certain amount of pre-sterilized PBS buffer is injected into the atomized liquid storage bottle, and then the ceramic atomizer is turned on to generate a large number of nano-sized droplets;

[0024] Then, a certain amount of pre-sterilized glycerol is injected into the vaporized liquid storage bottle, and then the ceramic vaporization core is turned on to heat and generate an appropriate amount of hydrophilic molecules;

[0025] Step 2: Turn on the vacuum pump. Under the action of negative pressure, the air and the hydrophilic molecules generated by heating the ceramic vaporization core mix and enter the condensation growth channel through the air inlet;

[0026] Under the low temperature provided by the temperature-control cylinder according to the display of the thermometer, the hydrophilic molecules entering the condensation growth channel and the water vapor in the air gradually condense on the surface of the aerosol, causing its volume to continuously increase and form droplets;

[0027] The liquid droplets are carried into the sampling bottle along with the air flow, or flow into the reflux liquid collection tank along the wall of the condensation growth channel and the inner wall of the sampling bottle;

[0028] Step 3: In the sampling bottle, the still suspended tiny droplets from the condensation growth channel fully contact with the nano-scale droplets produced by the ceramic atomizer, further aggregate and grow in the gas path due to the impact, and converge into a liquid flow in the polymerization reflux channel under the action of centrifugal force;

[0029] Under the action of gravity, the liquid flows along the bottom of the polymerization reflux channel pipeline, passes through the return liquid guide plate, and finally collects in the reflux liquid collection tank;

[0030] Step 4: After sampling, open the reflux liquid outlet and collect the reflux liquid into a sterile container for subsequent detection and analysis.

[0031] In some embodiments, the flow rate provided by the vacuum pump ranges from 5 L / min to 25 L / min, and the temperature provided by the temperature control cylinder differs from the temperature measured by the thermometer by 5° C. to 30° C.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. The present invention provides a ceramic vaporization core and a condensation growth channel. The ceramic vaporization core heats the glycerol in the vaporization liquid storage bottle to generate hydrophilic molecules. The hydrophilic molecules entering the condensation growth channel and the water vapor in the air gradually condense on the surface of the bioaerosol, causing its volume to continuously increase to form droplets. The condensation effect and the polymerization effect with the atomized droplets can gradually increase the volume of the aerosol in the environmental sample in the sampler, effectively preventing the escape of tiny aerosols and achieving the maximum capture of aerosols of different particle sizes in the air.

[0034] 2. The present invention provides a flow meter, a condensation growth channel, and a ceramic atomizer. A lower air flow rate is introduced into the flow meter, allowing the suspended microdroplets in the condensation growth channel to fully contact the nano-scale droplets produced by the ceramic atomizer. Due to the lower air flow rate and the buffering effect of the suspended droplets, the damage to microbial cells caused by the shear stress generated by the impact during the sampling process can be reduced, thereby maintaining the biological activity of the sample and improving the sampling efficiency.

[0035] 3. The present invention provides a reflux liquid guide plate to guide the reflux liquid flow into the reflux liquid collection tank. The reflux liquid guide plate can effectively prevent the reflux liquid from dripping onto the surface of the ceramic atomizer and affecting the atomization process, thereby effectively improving the stability of the sampler operation.

[0036] 4. The present invention sets the working parts as a downward flow gasification condensation system and an upward flow polymerization recovery system. Its structure is simple, efficient, compact and portable. All gas path components can be sterilized at high temperature and high pressure, and are suitable for various sampling conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0038] Figure 1 This is a schematic structural diagram of the air bioaerosol sampling device of the present invention.

[0039] Reference numerals:

[0040] Polymerization reflux channel 1 Condensation growth channel 9

[0041] Flow meter 2 Sampling bottle 10

[0042] Temperature control cylinder 3 Reflux liquid guide plate 11

[0043] Vacuum pump 4 Ceramic atomizer 12

[0044] Thermometer 5 Atomized liquid storage bottle 13

[0045] Air inlet 6 Reflux liquid collection tank 14

[0046] Gasified liquid storage bottle 7 Reflux liquid outlet 15

[0047] Ceramic gasification core 8 DETAILED DESCRIPTION

[0048] The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several changes and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0049] Example 1

[0050] like Figure 1 As shown, the air bioaerosol sampling device of the present invention includes a polymerization reflux channel, a flow meter, a temperature control cylinder, a vacuum pump, a thermometer, an air inlet, a vaporized liquid storage bottle, a ceramic vaporization core, a condensation growth channel, a sampling bottle, a reflux liquid guide plate, a ceramic atomizing plate, an atomized liquid storage bottle, a reflux liquid collecting tank, and a reflux liquid outlet. A flow meter is connected between the air inlet of the vacuum pump and the air outlet of the polymerization reflux channel to collect the flow rate. The air inlet of the polymerization reflux channel extends into the sampling bottle, and the end is connected to the reflux liquid guide plate. The top of the sampling bottle is connected to the condensation growth channel, and the bottom is connected to the reflux liquid outlet. An atomized liquid storage bottle with a top connected to a ceramic atomizing plate is fixed inside the sampling bottle, and the interlayer between the atomized liquid storage bottle and the sampling bottle is a reflux liquid collecting tank. The lower end of the air inlet of the condensation growth channel is connected to a vaporized liquid storage bottle with a ceramic vaporization core, and the upper end is connected to a thermometer that can be used to measure the air inlet temperature. The temperature control cylinder is a detachable refrigeration component as the outer shell of the device.

[0051] The vaporized liquid storage bottle, ceramic vaporization core, condensation growth channel, temperature control cylinder, air inlet, thermometer, and reflux liquid collection tank together constitute the downflow vaporization and condensation system. The atomized liquid storage bottle, ceramic atomizing plate, polymerization reflux channel, reflux liquid guide plate, and reflux liquid collection tank together constitute the upflow polymerization recovery system. The vaporized liquid storage bottle contains glycerol, which has good hydrophilicity and promotes the condensation and growth of the aerosol after vaporization. The atomized liquid storage bottle contains PBS buffer, which has a good salt balance and helps maintain microbial activity after atomization.

[0052] A method for sampling air bioaerosols comprises the following steps:

[0053] Step 1: Before sampling begins, place all components except the flow meter, temperature control cylinder, vacuum pump, and thermometer in an autoclave for high-temperature steam sterilization. At the start of sampling, inject a certain amount of pre-sterilized PBS buffer into the atomizing liquid storage bottle, then turn on the ceramic atomizing plate to produce a large number of nano-sized droplets. Inject a certain amount of pre-sterilized glycerol into the vaporizing liquid storage bottle, then turn on the ceramic vaporizing core to heat and produce an appropriate amount of hydrophilic molecules.

[0054] Step 2: Turn on the vacuum pump. Under the action of negative pressure, the air and the hydrophilic molecules generated by the heating of the ceramic vaporization core mix at the air inlet and enter the condensation growth channel. Under the action of the low temperature provided by the temperature control cylinder according to the thermometer reading, the hydrophilic molecules entering the condensation growth channel and the water vapor in the air gradually condense on the surface of the aerosol, causing its volume to increase continuously to form droplets. Later, they are entrained into the sampling bottle with the air flow, or flow into the reflux liquid collection tank along the wall of the condensation growth channel and the inner wall of the sampling bottle;

[0055] Step 3: In the sampling bottle, the still suspended tiny droplets from the condensation growth channel fully contact with the nano-scale droplets produced by the ceramic atomizer. Due to the impact, they further gather and grow in the gas path. Under the action of centrifugal force, they converge into a liquid flow in the polymerization reflux channel. Under the action of gravity, they flow along the bottom of the polymerization reflux channel pipeline through the reflux liquid guide plate and finally gather in the reflux liquid collection tank.

[0056] Step 4: After sampling, open the reflux liquid outlet and collect the reflux liquid into a sterile container for subsequent detection and analysis.

[0057] In step 2, the flow rate provided by the vacuum pump ranges from 5 L / min to 25 L / min; the temperature difference between the temperature provided by the temperature control cylinder and the temperature measured by the air inlet thermometer ranges from 5° C. to 30° C.

[0058] Working principle:

[0059] Under the negative pressure provided by the vacuum pump, the air and the hydrophilic molecules generated by the heating of the ceramic vaporization core are mixed at the air inlet and enter the condensation growth channel. Under the low temperature provided by the temperature control tube according to the thermometer display, the hydrophilic molecules entering the condensation growth channel and the water vapor in the air gradually condense on the surface of the aerosol, causing its volume to continue to grow and form droplets, which are then entrained into the sampling bottle with the air flow, or flow into the reflux liquid collection tank along the wall of the condensation growth channel and the inner wall of the sampling bottle.

[0060] In the sampling bottle, the still suspended tiny droplets from the condensation growth channel are in full contact with the nano-scale droplets produced by the ceramic atomizer. Due to the impact, they are further aggregated and grown in the gas path, and are converged into a liquid flow in the polymerization reflux channel under the action of centrifugal force. Under the action of gravity, they flow along the bottom of the polymerization reflux channel pipeline through the reflux liquid guide plate and finally gather in the reflux liquid collection tank.

[0061] In the description of this application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0062] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. The embodiments of this application and the features in the embodiments may be combined with each other in any manner unless there is a conflict.

Claims

1. An air bioaerosol sampling device, characterized in that: It comprises a vacuum pump (4) and a polymerization reflux channel (1), wherein the vacuum pump (4) is connected to one end of the polymerization reflux channel (1); The other end of the polymerization reflux channel (1) is connected to a reflux liquid guide plate (11), and the reflux liquid guide plate (11) is arranged in the sampling bottle (10); The top of the sampling bottle (10) is connected to one end of the condensation growth channel (9), the bottom of the sampling bottle (10) is connected to the reflux liquid outlet (15), an atomized liquid storage bottle (13) is provided inside the sampling bottle (10), and the top of the atomized liquid storage bottle (13) is connected to a ceramic atomizing plate (12); An air inlet (6) is provided on the condensation growth channel (9), the other end of the condensation growth channel (9) is connected to a gasification liquid storage bottle (7), and a ceramic gasification core (8) is provided at the bottom end of the gasification liquid storage bottle (7); The reflux liquid guide plate (11) prevents the reflux liquid flowing in the polymerization reflux channel (1) from dripping onto the ceramic atomizing plate (12); A reflux liquid collecting tank (14) is provided between the atomized liquid storage bottle (13) and the sampling bottle (10); The reflux liquid guide plate (11) drains the reflux liquid into the reflux liquid collection tank (14), and the reflux liquid outlet (15) discharges the reflux liquid; The vaporized liquid storage bottle (7), the ceramic vaporization core (8), the condensation growth channel (9), the temperature control cylinder (3), the air inlet (6), the thermometer (5) and the reflux liquid collecting tank (14) together constitute a downward flow vaporization and condensation system; The atomized liquid storage bottle (13), the ceramic atomizing plate (12), the reflux liquid guide plate (11), the polymerization reflux channel (1) and the reflux liquid collecting tank (14) together constitute an upward flow polymerization recovery system.

2. The air bioaerosol sampling device according to claim 1, characterized in that: The upper air inlet of the vacuum pump (4) is connected to the upper air outlet of the polymerization reflux channel.

3. The air bioaerosol sampling device according to claim 1, characterized in that: A flow meter (2) is provided between the vacuum pump (4) and the polymerization reflux channel (1).

4. The air bioaerosol sampling device according to claim 1, characterized in that: The upper end of the air inlet (6) is connected to a thermometer (5), and the thermometer (5) is used to measure the temperature of the air inlet (6).

5. The air bioaerosol sampling device according to claim 1, characterized in that: The temperature control cylinder (3) is detachably arranged outside the sampling bottle (10), and part of the pipeline of the polymerization reflux channel (1) and part of the pipeline of the condensation growth channel (9) extend into the interior of the temperature control cylinder (3).

6. The air bioaerosol sampling device according to claim 1, characterized in that: The liquid in the gasified liquid storage bottle (7) is glycerol, and the liquid in the atomized liquid storage bottle (13) is PBS buffer.

7. A method for sampling air bioaerosols, using the air bioaerosol sampling device according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1: Before sampling begins, all components except the flow meter (2), the temperature control cylinder (3), the vacuum pump (4) and the thermometer (5) are placed in a sterilizer for high-temperature steam sterilization; At the beginning of sampling, a certain amount of pre-sterilized PBS buffer is injected into the atomized liquid storage bottle (13), and then the ceramic atomizer (12) is turned on to generate a large number of nano-sized droplets; Then, a certain amount of pre-sterilized glycerol is injected into the gasification liquid storage bottle (7), and then the ceramic gasification core (8) is opened to heat and generate an appropriate amount of hydrophilic molecules; Step 2: Turn on the vacuum pump (4), and under the action of negative pressure, the air and the hydrophilic molecules generated by heating the ceramic gasification core (8) are mixed and enter the condensation growth channel (9) through the air inlet (6); Under the action of the low temperature provided by the temperature control cylinder (3) according to the display of the thermometer (5), the hydrophilic molecules entering the condensation growth channel (9) and the water vapor in the air gradually condense on the surface of the bioaerosol, causing its volume to continuously increase and form droplets; The liquid droplets are carried along with the air flow into the sampling bottle (10), or flow into the reflux liquid collection tank (14) along the wall of the condensation growth channel (9) and the inner wall of the sampling bottle (10); Step 3: In the sampling bottle (10), the still suspended tiny droplets from the condensation growth channel (9) fully contact with the nano-scale droplets produced by the ceramic atomizing plate (12), further aggregate and grow in the gas path due to the impact, and converge into a liquid flow in the polymerization reflux channel (1) under the action of centrifugal force; Under the action of gravity, the liquid flows along the bottom of the polymerization reflux channel (1) through the return liquid guide plate (11) and finally collects in the reflux liquid collection tank (14); Step 4: After the sampling is completed, the reflux liquid outlet (15) is opened and the reflux liquid is collected into a sterile container for subsequent detection and analysis.

8. The air bioaerosol sampling method according to claim 7, characterized in that: The flow rate provided by the vacuum pump (4) ranges from 5 L / min to 25 L / min, and the temperature provided by the temperature control cylinder (3) differs from the temperature measured by the thermometer (5) by 5° C. to 30° C.

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