Liquid sampling medium for aerosol sampling and preparation method and application thereof

Abstract

The invention provides a liquid sampling medium for aerosol sampling and a preparation method and application thereof, and belongs to the technical field of biological aerosol sampling, the liquid sampling medium comprises 30-70% by volume of a gum solution, an LB liquid culture medium and a defoaming agent; the liquid sampling medium is high in sampling efficiency, the activity of microorganisms in an aerosol sample can be kept, the storage stability of the aerosol sample is improved, a more reliable and effective means is provided for collection and analysis of biological aerosol, and the liquid sampling medium has important application value for disease monitoring, environment evaluation and biological safety research.

Description

Technical Field

[0001] The invention belongs to the technical field of bioaerosol sampling, and in particular relates to a liquid sampling medium for aerosol sampling, a preparation method and an application thereof. Background Art

[0002] At present, microorganisms in the air are generally collected in solid, semi-solid or liquid matrices, and then subjected to subsequent specific analysis. How to ensure that the microorganisms survive under the impact of the sampling airflow is a difficult problem. Therefore, choosing a sampling medium that can ensure the survival of microorganisms has become a key issue. There are basically no special reports on sampling media abroad. Only some sampling liquids are mentioned in air sampling reports. Most of the sampling liquids used are either the simplest sterile water or some simple inorganic salt buffers. These media only play a collection role, and the protection and stabilization effect on bacteria is weak, and they cannot meet the needs under certain special conditions. People's requirements for air quality are gradually increasing, so the sampling medium for air microorganisms should also be explored in depth. Other studies have found that the role of protecting microorganisms can be achieved by adding an appropriate amount of additives to the sampling liquid. A liquid impact sampler was used to sample aerosols of Yersinia pestis and Serratia marcescens, and the collection effect and protection of different sampling liquids on biological particles were observed. The study found that the addition of Tween 80 and olive oil to the sampling liquid can provide effective protection for the activity of Yersinia pestis sampled for 30 minutes. The pestis bacteria were affected during sampling, which may be caused by the components in the additives reducing the surface tension of water (Jiang Nan, Cheng Pengbo, Zhou Dongsheng. Study on the biological activity damage of Yersinia pestis aerosol generation and sampling process [J]. Chinese Journal of Disinfection, 2020, 37(06): 401-405.). Domestic scholars and researchers evaluated the collection ability of three different sampling liquids, PBS, SM liquid, and nutrient broth, for mycobacteriophage D29. The results were similar. The method used an all-glass liquid impact sampler AGI-30 to collect D29 aerosols and make judgments. The results showed that bacteriophage D29 had the strongest impact resistance in PBS containing trace amounts of Tween80, and it was suggested that adding appropriate additives for sampling could reduce aerosol losses (Liu Keyang, Du Qian, Wen Zhanbo, et al. Preliminary study on the spray and sampling medium of mycobacteriophage D29 aerosol [J]. Journal of the Academy of Military Medical Sciences, 2010, 34(04): 347-350.).

[0003] There are still some issues worth thinking about in the study of collection media: First, in the process of liquid sampling of bioaerosols, the protection of the activity of pathogens by the impact force of the sampling liquid is a key issue. Since the liquid sampling medium will generate a certain impact force when capturing aerosol particles, this impact force may cause physical damage to the pathogens, especially for those pathogens with fragile structures, such as viruses and certain bacteria. Small-sized viruses are more susceptible to this impact force due to their tiny volume and surface area, causing them to be injured or die. This not only affects the survival rate of pathogens, but also reduces the accuracy of subsequent experiments and analysis to a certain extent. Therefore, it is crucial to improve the efficiency and accuracy of bioaerosol sampling to develop sampling techniques that can reduce the impact of impact forces, or use milder sampling media to protect the integrity and activity of pathogens.

[0004] Secondly, when preparing the current collection fluid, attention is often paid to the biosafety of the target pathogens collected, but the efficiency and pathogen capture ability of the collection are ignored, as well as the long-term stability of the sample. This means that the sample has been inactivated or biosafety treated when it is collected, and the biosafety meets the requirements, but the sampling efficiency and pathogen capture ability of the current collection fluid are reduced. During the subsequent storage and transportation process, the sample may be degraded or mutated due to environmental changes, instability of the collection fluid components, or physiological activities of the microorganisms themselves. This instability may cause the activity of the microorganisms in the sample to decrease or even die, thereby affecting the accuracy and reliability of subsequent laboratory analysis such as culture, gene sequencing, and antigen detection.

[0005] In order to ensure that the collected samples can reflect the actual environmental conditions, the collection fluid needs to be further optimized to improve the ability to capture pathogens, protect the activity of pathogens, and enhance the storage stability of samples and the stability of subsequent testing. Summary of the invention

[0006] In view of this, the purpose of the present invention is to provide a liquid sampling medium for aerosol sampling, a preparation method and application thereof; the liquid sampling medium has high sampling efficiency, can maintain the activity of microorganisms in aerosol samples, and improve the storage stability of aerosol samples, providing a more reliable and effective means for the collection and analysis of bioaerosols, and has important application value for disease monitoring, environmental assessment and biosafety research.

[0007] The invention provides a liquid sampling medium for aerosol sampling, comprising a gum solution with a volume percentage of 30% to 70%.

[0008] Preferably, the volume percentage of the gum solution is 40% to 60%.

[0009] Preferably, the liquid sampling medium comprises the following components in volume percentage: 30% to 70% of a gum solution, 8% to 12% of a defoaming agent, and the remainder of LB liquid culture medium.

[0010] Preferably, the concentration of the gum solution is 50-150 mg / mL.

[0011] Preferably, the defoamer is a silicone defoamer.

[0012] Preferably, the pH value of the liquid sampling medium is 8.4-8.6.

[0013] The present invention provides a method for preparing the liquid sampling medium, comprising the following steps:

[0014] The gum solution, LB liquid culture medium and defoaming agent are mixed, and then the pH value is adjusted to 8.4-8.6 to obtain the liquid sampling medium.

[0015] The invention provides application of the liquid sampling medium in microbial aerosol sampling.

[0016] Preferably, the microorganisms include bacteria, fungi and viruses.

[0017] Preferably, the bacteria include Staphylococcus aureus.

[0018] Compared with the prior art, the present invention has the following beneficial effects: the present invention provides a liquid sampling medium for aerosol sampling, and by adding gum to the liquid sampling medium, the activity of pathogens can be better maintained, the sampling efficiency can be improved, and the stability of sample preservation can be ensured.

[0019] First of all, gum, as a natural polysaccharide, has unique physical and chemical properties. It not only has a certain viscosity, which can increase the anti-foaming ability of the liquid and reduce the surface tension of water, but also has a protective effect on the sampling objects (such as bacteria, viruses, fungi, etc.). The viscosity of gum helps to reduce the impact of the liquid on the sampling object during the sampling process, thereby reducing the risk of damage or inactivation of the sampling object. This protection is particularly important for small-particle viruses and vulnerable microorganisms.

[0020] Secondly, the addition of gum improves the rheological properties of the sampling liquid, allowing the liquid to capture aerosol particles more effectively when passing through the sampler. This improved capture efficiency not only improves sampling efficiency, but also reduces interference with the environment, making the sampling process more accurate and controllable. In addition, the anti-foaming properties of gum also help reduce the bubbles that may be generated during the sampling process, preventing bubbles from interfering with the normal operation of the sampler, further ensuring the accuracy of the sampling results.

[0021] Furthermore, the addition of gum can also help improve the storage stability of samples. After collection, samples often need to be processed and analyzed within a certain period of time. Gums can maintain the physiological activity of microorganisms to a certain extent, slow down their metabolic process, and thus extend the effective storage time of samples. This is especially important for samples that need to be transported for a long time or cannot be analyzed immediately after collection. In addition, gum also has certain antibacterial properties, which can inhibit the growth of bacteria that may exist in the sample, further ensuring the stability of the sample.

[0022] The present invention provides a condition closer to the natural living environment for microorganisms by adjusting the pH value and osmotic pressure of the sampling liquid, thereby further improving the activity and stability of the sample.

[0023] In summary, the present invention not only improves the sampling efficiency of bioaerosols by adding gum to the sampling liquid, but also effectively protects the activity of pathogens and ensures the storage stability of samples. This innovative improvement provides a more reliable and effective means for the collection and analysis of microbial aerosols, and has important application value for disease monitoring, environmental assessment and biosafety research. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is the diagram of the aerosol simulation chamber;

[0025] Figure 2 This is a comparison chart of the collection results of the five sample liquids in Example 1 using the Anderson sampler;

[0026] Figure 3 This is a comparison chart of the collection results of the five sample liquids in Example 1 using the BIO Capturer-6 sampler. DETAILED DESCRIPTION

[0027] The invention provides a liquid sampling medium for aerosol sampling, comprising a gum solution with a volume percentage of 30% to 70%.

[0028] In the present invention, the liquid sampling medium preferably comprises a gum solution with a volume percentage of 40% to 60%.

[0029] Further preferably, the liquid sampling medium of the present invention comprises the following components in volume percentage: 30% to 70% of a gum solution, 8% to 12% of a defoaming agent, and the remainder of LB liquid culture medium.

[0030] In the present invention, the liquid sampling medium includes a gum solution, and the concentration of the gum solution is preferably 50-150 mg / mL, more preferably 80-120 mg / mL, and further preferably 100 mg / mL; in the present invention, the gum solution is preferably prepared using sterile enzyme-free water, and the volume percentage of the gum solution in the liquid sampling medium is preferably 45%-55%, and further preferably 50%.

[0031] In the present invention, the liquid sampling medium includes a defoamer, and the defoamer is preferably an organosilicon defoamer; the volume percentage of the organosilicon defoamer in the liquid sampling medium is preferably 8% to 12%, more preferably 9% to 11%, and even more preferably 10%.

[0032] In the present invention, the liquid sampling medium also includes LB liquid culture medium, and the LB liquid culture medium is preferably prepared by mixing commercially available LB broth culture medium and water. The ratio of the LB broth culture medium to water is preferably 1g:30-50ml, more preferably 1g:35-45ml, and even more preferably 1g:40ml.

[0033] In the present invention, the pH value of the liquid sampling medium is preferably 8.4-8.6, and more preferably 8.5; the present invention has no special limitation on the reagent for adjusting the pH value, and conventional pH adjusters in the art can be used; the pH value of the liquid sampling medium can provide a condition for the microorganisms in the sample that is closer to the natural living environment, thereby further improving the activity and stability of the sample.

[0034] The present invention provides a method for preparing the liquid sampling medium, comprising the following steps:

[0035] The gum solution, LB liquid culture medium and defoaming agent are mixed, and then the pH value is adjusted to 8.4-8.6 to obtain the liquid sampling medium.

[0036] In the present invention, the gum solution is preferably mixed with a portion of the LB liquid culture medium, an organosilicon defoamer is added, and then the pH value is adjusted, and finally the volume is fixed with the remaining LB liquid culture medium.

[0037] The present invention also provides the use of the liquid sampling medium in microbial aerosol sampling. In the present invention, the microorganisms include bacteria, fungi and viruses. In the specific implementation of the present invention, Staphylococcus aureus and influenza A virus are taken as examples.

[0038] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0039] Reagents used in the following examples:

[0040] PBS Phosphate Buffer (pH 7.4):

[0041] Take 1.36g of potassium dihydrogen phosphate, add 79ml of 0.1mol / L sodium hydroxide solution, and dilute with water to 200ml.

[0042] Preparation of LB liquid culture medium: weigh 25.0 g LB broth culture medium into 1000 ml distilled water, divide into portions, and sterilize by high pressure at 121°C for 15 min for later use.

[0043] Preparation of 30% gum solution: Weigh 3 g of gum powder on a balance and transfer it into a 250 ml conical flask. Add 30 ml of enzyme-free sterile water to mix and prepare a 100 mg / ml gum solution. Then add 70 ml of LB liquid culture medium to make a total solution volume of 100 ml. After sealing, autoclave at 121°C for 15 min for use.

[0044] Preparation of 50% gum solution: Weigh 5 g of gum powder on a balance, transfer to a 250 ml conical flask, add 50 ml of enzyme-free sterile water to mix and prepare a 100 mg / ml gum solution, then add 50 ml of LB liquid culture medium to make a total solution volume of 100 ml. After sealing, autoclave at 121°C for 15 min for use.

[0045] Preparation of 80% gum solution: Use a balance to weigh 8g of gum powder, transfer it into a 250ml conical flask, and add 80ml of enzyme-free sterile water to mix and prepare a 100mg / ml gum solution. Then add 20ml of PBS liquid to make a total solution volume of 100ml. After sealing, sterilize it at 121℃ for 15min and set aside.

[0046] Preparation method of SDS solution: Weigh 1.5g of SDS powder on a balance, transfer it into a 250ml conical flask, add 100ml of enzyme-free sterile water to the flask and mix to prepare a 0.015g / ml SDS solution.

[0047] Example 1 Bacteria sampling

[0048] Liquid sampling medium:

[0049] PBS phosphate buffer (pH 7.4), LB medium, 30% gum solution, 50% gum solution, 80% gum solution.

[0050] Preparation of Staphylococcus aureus suspension: Take out the standard sample of Staphylococcus aureus (CGMCC1.3374, provided by the Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences) from the refrigerator and equilibrate to room temperature. After being fully sterilized in a biosafety cabinet, use a disposable inoculation loop to pick up an appropriate amount of Staphylococcus aureus sample, divide and mark on a TSA plate, place it in a 37°C incubator for 24 hours, use a 200 μl pipette tip to pick up two standard single colonies of Staphylococcus aureus and mix them with 2 mL of LB liquid culture medium, and then incubate in a 37°C shaker for 8 hours to make a concentration of 5×10 8 CFU / ml stock solution, dilute the stock solution with sterile enzyme-free water to a concentration of 10 6 CFU / ml, as the generating solution, can be divided into test tubes. At the same time, prepare 10 7 CFU / ml is used as the second concentration generating liquid, and the specific method of generating aerosol is as follows:

[0051] In 1m 3 Aerosol Chamber ( Figure 1 ), set the aerosol spray parameters, spray time 3min, flow rate 2mL / min, spray volume 5mL, sampling time 15min, experimental temperature controlled at 20℃~25℃, humidity controlled at 40%~45% of room temperature. Place an Anderson sampler or enrichment-6 sampler (BIO Capturer-6) in the cabin, use two different concentrations of white Staphylococcus aureus suspensions, and carry out the following simulation experiments (Table 1), prepare four 50ml centrifuge tubes, take 5ml of white Staphylococcus aureus suspension and add it to the first centrifuge tube, fill the second centrifuge tube with 40ml disinfectant, and use the other two as waste liquid tubes, and put the four centrifuge tubes into the test tube rack of the bioaerosol cabin generator. Use the generator to spray bacteria, use 5ml of the generating liquid with a concentration of 10 6 CFU / ml is used for simulation experiment to form aerosol of Staphylococcus aureus in the cabin. After the occurrence, it is collected by using a sampler. 20ml PBS solution and two drops of magnetic beads (magnetic beads are used to adsorb bacteria or viruses in the sampling liquid) are placed in the sampling bottle. After the sampling bottle and the sampler are connected, they are placed in the generation cabin together. After the collection is completed, the bioaerosol cabin is disinfected. Mark the PBS sampling liquid after the aerosol sample is collected and take it out for use. After the collection is completed, spray disinfection is carried out for 25 minutes and the air is self-purified for 20 minutes. Repeat the above operation for other types of sampling liquids.

[0052] Table 1. Overall experimental setup

[0053]

[0054] The Anderson sampler was used to compare the collection effects of different collection media. Each sampling liquid was repeated three times in parallel. Two groups of Anderson were used in each experiment, divided into Group A and Group B. Each sampling liquid had 6 samples, totaling 30 samples. The concentration of Staphylococcus aureus captured by the Anderson sampler was calculated (according to Formula 1), and the average value of the three repeated collection results of each group of Anderson was taken for comparison. The sampling effects of each collection medium were compared by comparing the average values. The concentration of each experimental liquid was 10 6 CFU / ml, keep the concentration of the generating solution consistent. Use WPS Excel to calculate the average value and relative average deviation. (See Table 2).

[0055] According to GB / T38517-2020, the formula for calculating the concentration of microorganisms in the air is as follows (1).

[0056]

[0057] In the formula, C F is the concentration of microorganisms in the air sample, expressed in colony forming units per cubic meter (CFU / m 3 );n CFU is the total bacterial count on the six-level sampling plate, in colony forming units (CFU); V is the sampling flow rate, in liters per minute (L / min); t is the sampling time, in minutes (min).

[0058] The Anderson sampler was set with a sampling time t of 36 min, a sampling flow rate V of 28.3 L / min, and a total sampling volume of 1000 L.

[0059] Table 2 Anderson sampler capture of Staphylococcus aureus results (CFU / m 3 )

[0060]

[0061]

[0062] According to the average calculation results, 50% gum had the highest concentration of collected microorganisms for Staphylococcus aureus, with an average value of 213.67 for group A and 156.33 for group B. PBS buffer had the lowest concentration of collected microorganisms for Staphylococcus aureus, with an average value of 1 for both group A and group B.

[0063] The BIO Capturer-6 sampler was used to compare the collection effects of different collection media. Each sampling liquid was repeated three times in parallel. The experiment was divided into three groups, A, B, and C, with 3 samples of each sampling liquid, for a total of 15 samples. The BIO Capturer-6 sampler was set to automatically stop when the sampling volume reached 1000L, the sampling flow rate V was 100L / min, and the total sampling volume was 1000L.

[0064] The concentration of Staphylococcus aureus captured by the BIO Capturer-6 sampler was calculated (according to Formula 1), and the average value of the results of three repeated experiments on different types of sampling liquid was taken for comparison. 6 CFU / ml, keep the concentration of the generating solution consistent. Use WPS Excel to calculate the average value and relative average deviation. (See Table 3).

[0065] Table 3 Results of capturing Staphylococcus aureus microorganisms by BIO Capturer-6 sampler (CFU / m 3 )

[0066]

[0067]

[0068] According to the average calculation results, the concentration of collected microorganisms of 50% gum against white Staphylococcus aureus was the highest, and the average value of the three groups was 20.67. The concentration of collected microorganisms of PBS buffer against white Staphylococcus aureus was the lowest, and the average values ​​of the three groups were all 0.33.

[0069] Depend on Figure 2 It can be seen that the results of the Anderson sampler collecting microbial concentrations showed that 50% gum had the best effect, followed by LB liquid culture medium, then 30% gum, then 80% gum, and finally PBS. Figure 3 It can be seen that the results of microbial concentration collected by BIO Capturer-6 sampler show that 50% gum has the best effect, followed by LB liquid culture medium, then 30% gum, then 80% gum, and finally PBS. It can be seen that the results of microbial concentration collected by Anderson sampler and BIO Capturer-6 sampler are consistent in the order from high to low for the five sampling liquids.

[0070] Example 2 Virus sampling

[0071] Liquid sampling medium:

[0072] PBS phosphate buffer (pH 7.4), LB medium, 30% gum solution, 50% gum solution, 80% gum solution.

[0073] Virus:

[0074] Influenza A virus (H1N1) RNA liquid indoor quality control product BNCC372922 (hereinafter referred to as influenza A simulation virus).

[0075] Anderson sampler collection experiment

[0076] The sampling parameters of the Anderson sampling pump were set to a sampling volume of 1000L, a sampling flow rate of 28.3L / min, and a collection time of 36min. A 10ml plate was placed on each of the 5th and 6th layers of the Anderson. Two parallel Anderson six-stage sampling heads were placed in the simulation test cabin, namely Anderson A and Anderson B. Two Anderson sampling pumps were placed in the control cabin, and the Anderson six-stage suction nozzle was connected to the silicone suction pipe corresponding to the right sampling port. The influenza A simulation virus (the stock solution was diluted 10 5 Times) to conduct a simulation experiment, use the generator to spray samples, and generate influenza A simulated virus aerosol in the cabin. After the spray is over, open the aerosol outlet ball valve, remove the sampling port covers of all samplers in the experimental cabin, start the sampling pump of the control cabin and sample according to the previously set sampling time. After the collection is completed, buckle the cover on the sampler and close the aerosol outlet ball valve. Spray disinfection for 25 minutes and air self-purification for 20 minutes. Take out the Anderson sampler, each sampler obtains two samples, and a total of 4 samples are obtained in one experiment. Pour the sampling liquid in the plate into the corresponding sampling bottle, and add 1 drop of magnetic beads for standby use, where the magnetic beads are used to adsorb the virus in the sample. To ensure the reliability and consistency of the result data, each sampling liquid is repeated 3 times, and a total of 12 samples are obtained. Similarly, the same operation is performed on the remaining sampling liquids as above.

[0077] Magnetic bead enrichment method to treat sample fluid

[0078] Remove the sampling bottle and place it on the corresponding suction cup to absorb the magnetic beads. Use a pipette to take 400μl of the supernatant in the sampling bottle into a 1.5ml EP tube. Discard the supernatant in the sampling bottle and retain the magnetic bead liquid. Then remove the suction cup and transfer the remaining magnetic beads in the bottle into the EP tube containing 400μl of supernatant to mix.

[0079] Nucleic acid extraction and PCR detection

[0080] Place the EP tube mixed with magnetic beads on a magnetic stand to fix the magnetic beads, discard the supernatant, remove the EP tube and add 300μl SDS liquid, mix it with the magnetic beads, elute the virus on the magnetic beads into SDS, and then place the EP tube back on the magnetic stand to fix the magnetic beads. The virus sample is retained in the SDS supernatant. Add 300μl of sample to the 1st and 7th columns of the 96-well plate, place the 96-well plate in the NPA-32P fully automatic nucleic acid extraction and purification instrument, install the magnetic rod sheath, and after the automation program is completed, transfer the eluate from the 5th and 11th columns to a clean nuclease-free centrifuge tube. PCR detection was performed on the machine using the Australian East A influenza virus kit. Pathogenic detection was carried out in the virus sample in the LineGene 9600Plus fluorescent quantitative polymerase chain reaction detection system, and the operation steps were carried out according to the instructions.

[0081] Table 4 Experimental settings

[0082]

[0083] Anderson samplers were used to compare the collection effects of different collection media. Three parallel experiments were repeated for each sampling liquid. Two groups of Andersons were used in each experiment, divided into group A and group B.

[0084] The Anderson sampler was set with a sampling time of 36 minutes, a sampling flow rate of 28.3 L / min, and a total sampling volume of 1000 L.

[0085] Table 5 Anderson sampler capture influenza A simulation virus results (Ct value)

[0086]

[0087]

[0088]

[0089] According to the principle that the smaller the Ct value, the higher the concentration, the average value calculation results in Table 5 show that the concentration of collected microorganisms for influenza A simulated virus is the highest for 50% gum, and the concentration of collected microorganisms for influenza A simulated virus is the lowest for LB buffer.

[0090] BIO Capturer-6 sampler collection experiment

[0091] The instrument was set up with a sampling volume of 1000L, a sampling flow rate of 100L / min, and a sampling time that automatically stopped when the set volume was reached. The sampling bottle corresponding to the BIO Capturer-6 sampler was filled with 20ml of PBS sampling solution and three drops of magnetic beads. The sampling bottle was connected to the sampler and placed in the simulation test chamber. The influenza A virus simulation (the stock solution was diluted 10 5The simulation experiment was carried out at 100 times (times), and the virus was sprayed by the generator to generate influenza A simulated virus aerosol in the cabin. After the occurrence, it was collected using BIO Capturer-6. After the collection, the sampling bottle was removed and the bottle cap was tightened. The bioaerosol cabin was disinfected, and the air was self-purified for 20 minutes after spray disinfection for 25 minutes. In order to ensure the reliability and consistency of the result data, each sampling liquid was repeated 3 times, and a total of 3 samples were obtained. Similarly, the other types of sampling liquids were operated in the same way as above.

[0092] The BIO Capturer-6 sampler was used to compare the collection effects of different collection media. Each sampling liquid was repeated three times in parallel. The experiment was divided into three groups, A, B, and C, with 3 samples for each sampling liquid, for a total of 18 samples. The average value of the three repeated experimental results of different sampling liquids was calculated for comparison. The average value and relative average deviation were calculated using WPS Excel. (See Table 6).

[0093] Table 6 Results of capturing influenza A virus simulation by BIO Capturer-6 sampler (Ct value)

[0094]

[0095]

[0096] The results calculated based on the average values ​​showed that the concentration of 50% gum against influenza A simulated virus was the highest, while the concentration of samples collected with PBS buffer was the lowest.

[0097] For virus aerosol sampling, the results of the Anderson sampler collecting microbial concentrations showed that 50% gum had the best effect, followed by DMEM culture medium, and then PBS buffer. The results of the BIO Capturer-6 sampler collecting virus concentrations showed that 50% gum had the best effect, followed by DMEM culture medium, and then 30% gum. It can be seen that when the Anderson sampler and the BIOCapturer-6 sampler collected the same virus concentration, the optimal sampling medium for the six sampling solutions was the same, that is, the sampling solution with 50% gum added.

[0098] It can be seen from the above embodiments that the present invention provides a liquid sampling medium for aerosol sampling. By adding gum to the liquid sampling medium, the activity of pathogens can be better maintained, the sampling efficiency can be improved, and the storage stability of the sample can be ensured.

[0099] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A liquid sampling medium for aerosol sampling, characterized in that: The invention comprises a gum solution with a volume percentage of 30% to 70%.

2. The liquid sampling medium according to claim 1, characterized in that: The invention comprises a gum solution with a volume percentage of 40% to 60%.

3. The liquid sampling medium according to claim 1 or 2, characterized in that: The liquid sampling medium comprises the following components in volume percentage: 30% to 70% of a gum solution, 8% to 12% of a defoaming agent and the remainder of an LB liquid culture medium.

4. The liquid sampling medium according to claim 3, characterized in that: The concentration of the gum solution is 50-150 mg / mL.

5. The liquid sampling medium according to claim 3, characterized in that: The defoamer is an organosilicon defoamer.

6. The liquid sampling medium according to claim 3, characterized in that: The pH value of the liquid sampling medium is 8.4-8.

6.

7. The method for preparing a liquid sampling medium according to any one of claims 3 to 6, characterized in that: The following steps are involved: The gum solution, LB liquid culture medium and defoaming agent are mixed, and then the pH value is adjusted to 8.4-8.6 to obtain the liquid sampling medium.

8. Use of the liquid sampling medium according to any one of claims 1 to 6 in microbial aerosol sampling.

9. The use according to claim 8, characterized in that: The microorganisms include bacteria, fungi and viruses.

10. The use according to claim 9, characterized in that: The bacteria include Staphylococcus albus.

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