CN106482988A - A kind of Portable high-flow air sampler - Google Patents

Abstract

The invention discloses a kind of Portable high-flow air sampler, including blower fan, collection pipeline, humidification sampling head, sampling media, bracing frame, battery and circuit control module, wherein, one end of collection pipeline is seamless with blower fan is fixedly connected, and the other end installs humidification sampling head；The position for being close to blower fan inside collection pipeline is provided with bracing frame, and sampling media is placed on bracing frame；By battery power fan operation；The particulate matter of in the air enters collection pipeline under blower fan driving, is sampled capture medium.The sampler has the advantages such as small, flow is big, collecting efficiency is high, can be widely applied to the sampling of various site environment aerosols, has good application prospect in fields such as environmental monitorings.

Description

A Portable Large Flow Air Sampler

technical field

The invention relates to an air sampler, in particular to a large-flow, high-efficiency and portable air sampling device and sampling method, which can be widely used in the collection and detection of particulate matter in indoor and outdoor ambient air, especially the rapid screening and screening of pathogenic microorganisms. monitor.

Background technique

At present, air pollution has attracted increasing attention worldwide, seriously threatening the health of residents. In addition to chemical pollutants, there are also a large number of biological aerosols in the air, such as bacteria, viruses, and fungal particles. Studies have shown that exposure to bioaerosols can cause many health problems, such as respiratory infections, allergies, etc., and the generation, diffusion, and transmission of bioaerosols can aggravate this hazard, (such as SARS in 2003, H1N1 in 2009, H5N9 in 2013 and major outbreaks such as MERS in 2015). Therefore, rapid detection and even real-time monitoring of bioaerosols to detect potential hazards becomes particularly important. However, as a crucial first step in the rapid detection and even real-time monitoring of bioaerosols, the effective collection of air samples has always been a difficult problem.

At present, the two most widely used samplers are Biosampler (SKC) and Anderson sampler designed by using the impact principle. The former collects air samples in liquid media, overcomes the problems of particle rebound and secondary aerosolization, and has a flow rate of 12.5 L/min; the latter collects air samples on solid medium, is an international standard bioaerosol collection method, has been used for more than 50 years, and has a flow rate of 28.3L/min. However, both of these methods require an air pump and rely on alternating current, making them difficult to carry and use on the spot. In addition, the sampling flow rate of the two methods is too low to be developed for rapid detection or even real-time monitoring of ambient air. At the same time, the Anderson sampler has a high impact velocity (up to 24m/s), which will cause impact damage to microorganisms, resulting in loss of cultivability, resulting in a decrease in the concentration of cultivable microorganisms, resulting in an underestimation of the concentration level in the environment.

The rise of gene amplification methods represented by PCR has significantly reduced the minimum concentration of biological sample detection and improved the efficiency of microbial detection. The emergence of constant temperature amplification method has further shortened the reaction time and simplified the reaction process; The emergence of chemical biosensors (such as silicon nanowire field effect transistors) can convert microbial biological signals into electrical signals without delay, thus making automatic online monitoring of microorganisms possible. However, the concentration of pathogenic bacteria in the air is sometimes very low, especially for some highly pathogenic pathogens, the development of high-flow rapid portable samplers is very important. Effective use of existing technologies for rapid detection of bioaerosols must rely on more powerful bioaerosol samplers to collect larger volumes of air samples in the shortest possible time and transfer them into liquids for gene amplification. Enhanced or specific electrochemical reactions.

Contents of the invention

The present invention aims to provide a portable air particle sampler with a super-large flow rate (over 1 cubic meter per minute), which can collect more aerosol particles in the shortest possible time to facilitate subsequent analysis and detection.

The main technical principles of the present invention are as follows: lithium batteries are used as the power source, a miniature high-volume fan drives air through the collection pipe, and an agar medium is installed at the center of the bottom of the pipe. In order to further improve the collection efficiency, a humidification sampling head is installed at the air inlet of the collection pipeline to overcome the drying effect, increase the moisture absorption of small particles, and further reduce the impact damage to biological particles and reduce the secondary ejection of collected particles. Technical scheme of the present invention is as follows:

A portable large-flow air sampler, including a fan, a collection pipe, a humidification sampling head, a sampling medium, a support frame, a battery and a circuit control module, wherein one end of the collection pipe is seamlessly and fixedly connected to the fan, and the other end is installed with a humidification sampling head A support frame is provided at a position close to the fan inside the collection pipeline, and the sampling medium is placed on the support frame; the fan is connected to a battery through a circuit control module, and the battery drives the fan to run.

For the convenience of holding, the fan can be erected on a panel, and a handle for holding is installed on the panel. The panel can be made of engineering plastics, the handle can be a Z-shaped one-handed handle made of stainless steel, and fixed on the panel with self-tapping screws.

The fan is a miniature high-volume fan, preferably with a diameter of 140±60mm, a rated voltage of 5-24V, a rated current of 0.3-6A, an air volume of 30-300CFM, the best diameter of 12cm, a rated voltage of 12V, and a rated Current 3A, air volume 200CFM.

Further, the collection pipeline is preferably a variable-diameter collection pipeline, the caliber of the end where the humidification sampling head is installed (ie, the air inlet) is small, and the caliber of the end connected to the fan (ie, the air outlet) is relatively large.

In order to facilitate the picking and placing of the collection medium, a half cylinder is formed by cross-cutting the side wall of the lower part of the collection pipe (near the end of the fan). The connecting line is the diameter of the pipe cross-section circle), so that the semi-cylinder can be rotated outwards to open. On the inner wall of the outwardly rotatable semi-cylinder, a support tray can be fixed by screws as a support frame for carrying the sampling medium. In one embodiment of the present invention, the support tray is located about 1 cm above the blower fan, and is a circular tray whose center coincides with the center of the cross-section of the collection pipeline, and its diameter is slightly larger than that of the culture dish to place and fix the culture medium. When the semi-cylinder is rotated outwards to open, the culture medium can be conveniently placed and taken.

The material of the collection pipeline can be metal (such as stainless steel, aluminum alloy) or plastic (such as PVC, ABS, PC), etc., but the inner wall of the pipeline is coated with polytetrafluoroethylene. The inner diameter of the air inlet is preferably 10-100 mm, and the inner diameter of the air outlet is preferably 80-200 mm. In one embodiment of the present invention, the collection pipe is made of polytetrafluoroethylene, the inner diameter of the air inlet is 50 mm, the inner diameter of the air outlet is 100 mm, and the height of the semi-cylinder formed by cross cutting is 20 mm.

The humidification sampling head is preferably an annular pipe-shaped container, which is provided with one or more atomization sheets for ultrasonic atomization. The sheet atomizes the sterile water in the pipe container through the ultrasonic vibration and sprays it out through the nozzle hole. The inner diameter of the humidification sampling head is the outer diameter of the air inlet of the collection pipe, which can be installed at the air inlet of the collection pipe. In one embodiment of the present invention, the difference between the inner and outer diameters of the annular tube of the humidification sampling head is 10mm, the height is 10-50mm, and the diameter of the spray holes on the inner wall is about 5mm.

The sampling medium can be an agar solid medium, which is used to collect cultivable microorganisms in the air, including bacterial culture medium and fungal culture medium, for example: TSA bacterial culture medium is used to collect bacterial aerosols, and Sabouraud medium is used to collect Fungal aerosols.

The sampling medium can also be a liquid, which is used to collect suspended particulate matter in the air, including but not limited to cultivable microorganisms. The liquid sampling medium is preferably a non-volatile liquid, such as sterile water, liquid culture medium, organic solvent, oil and the like.

The battery is preferably a lithium-ion rechargeable battery, such as a lithium-ion battery with a voltage of 12V and a capacity of 20000mAh.

The preferred main control core of the circuit control of the sampler is a single-chip microcomputer. The control circuit adopts the double closed-loop control mode of speed and current to enhance the mechanical characteristics and anti-interference ability of the motor, and ensure the constant speed of the fan, so as to realize the quantitative volume sampling of air by setting the sampling time. The defogging sheet is located in the humidification sampling head, and other circuits and components for ultrasonic atomization are also integrated on the circuit board.

Beneficial effects of the present invention: the portable large-flow air sampler provided by the present invention overcomes some defects in current air sampling, such as the current gold standard method—Anderson sampler has low flow rate, needs an external air pump, and has serious surface impact damage , significant drying effect and other issues, the present invention adopts an open impact sampling method, and the fan drives the air to impact the medium to achieve efficient sampling of biological particles. The sampler is small in size, large in flow rate, and high in collection efficiency, and can be widely used in the environment Bioaerosol sampling has good application prospects in environmental monitoring and other fields. The main features are:

(1) The flow rate of the sampler is large, reaching 1000L/min, but the impact speed on the medium is lower than 10m/s, and the number of cultureable microorganisms collected per unit time is greatly increased. The sampler is small and portable, and can be used in environmental biological It is widely used in aerosol on-site sampling and laboratory microbial culture.

(2) Use a humidifying sampling head to increase the moisture absorption of small particles, improve the collection efficiency, and reduce the impact damage to biological particles;

(3) When the sampling medium is changed to liquid, the sampler can effectively detect the biological components in the air in combination with biochemical analysis methods such as ELISA, PCR and constant temperature amplification.

Description of drawings

Fig. 1 is a schematic structural view of a portable high-flow sampler according to an embodiment of the present invention, wherein A is a side view, and B is a top view; 1-fan, 2-collection pipeline, 3-humidification sampling head, 4-sampling medium, 5- Support frame, 6-battery, 7-handle, 8-panel, 9-screw, 10-lock, 11-control circuit.

Fig. 2 is a schematic top view of the connection between the support frame and the pipeline, in which 2-acquisition pipeline, 5-support frame, 10-lock, 12-screw, 13-hinge.

Fig. 3 shows the biological efficiency of the portable high-flow sampler according to the embodiment of the present invention in collecting bacterial particles in the air.

detailed description

Below in conjunction with accompanying drawing, further describe the present invention in detail through embodiment.

Figure 1 is a schematic diagram of the structure of a portable high-flow air sampler. The sampler consists of a micro fan 1 and a sampling pipeline 2 to form a cylindrical sampling space. The optimum diameter of fan 1 is 120mm, the rated voltage is 12V, the rated current is 3A, and the air volume is 200CFM. Use four M5 screws 9 to fix the fan 1 on the panel 8 at a certain height, not less than 40mm. Panel 8 is made of ABS engineering plastics, which is strong and easy to process, with a size of 120mm×200mm and a thickness of 5mm. The collection pipeline 2 is a variable-diameter collection pipeline, and the inner diameter is changed from 50mm to 100mm. The variable-diameter collection pipe 2 is seamlessly bonded to the fan 1 so that the collection pipe 2 faces the fan. A humidification sampling head 3 is placed above the collection pipe 2. The height of the humidification sampling head 3 is 50 mm. Two atomization sheets for ultrasonic atomization are installed inside, and two water mist spray holes are arranged symmetrically in the lower part of the inner wall. At the center of the lower part of the collection pipe 2 10 mm away from the blower is a support frame 5 for placing the culture medium, that is, the sampling medium 4 . The support frame 5 is a circular tray, as shown in Figure 2, its center coincides with the center of the cross-section of the collection pipeline, and is fixed on the processed semi-cylinder that can rotate outwards by screws 12, and the semi-cylinder and one end of the parent pipeline are hinged 13 connection, the other end is connected by a lock 10, which can be rotated outward to facilitate placement and taking of culture medium.

The lithium battery 6 has a capacity of 20000mAh, which can drive the sampler to work continuously for more than 6 hours. The main control core of the control circuit 11 is a single-chip microcomputer, and the control mode is a double closed-loop of speed and current. Through testing and calibration, the flow rate of the sampler is set to 1000L/min, and the sampling time (sampling air volume) can be set arbitrarily, generally 1-10min (1m ^{3-10m 3 )} . After placing the culture medium, turn on the switch, select the appropriate sampling time and start sampling. The fan drives the air to enter the pipeline from the air inlet of the sampling pipeline (that is, the end of the humidification sampling head). The particles carried by the airflow meet and mix with the water mist sprayed from the water mist spray hole. The particles carried by the airflow hit the medium and are captured. The measured impact velocity of particles in the center of the medium was 8.32m/s, and gradually decreased to 2.35m/s outward along the radius of the medium, which was generally much lower than the impact velocity of 24m/s of the Anderson sampler.

Figure 3 shows the experimental results of the portable high-flow sampler collecting cultivable bacteria from outdoor air. It can be seen from the figure that the total number of culturable bacteria collected by using the sampler for 1 minute, 5 minutes, and 10 minutes is higher than the total number of culturable bacteria collected by the gold standard method - Anderson sampler for 10 minutes. It can be seen that the collection efficiency of the portable high-flow sampler is greatly improved, and the sampling time can be greatly shortened during on-site detection.

Claims (10)

1. a kind of Portable high-flow air sampler, including blower fan, collection pipeline, humidifies sampling head, sampling media, support Frame, battery and circuit control module, wherein, one end of collection pipeline is seamless with blower fan to be fixedly connected, and the other end is installed humidification and adopted Sample head；The position for being close to blower fan inside collection pipeline is provided with bracing frame, and sampling media is placed on bracing frame；The blower fan leads to Oversampling circuit control module connects battery, by battery power fan operation.

2. Portable high-flow air sampler as claimed in claim 1, it is characterised in that the blower fan is erected at a face On plate, it is provided with panel for hand-held lever.

3. Portable high-flow air sampler as claimed in claim 2, it is characterised in that the panel material is engineering plastic Material；The lever is Z-type one-handed grip, and material is stainless steel, is fixed on panel by tapping screw.

4. Portable high-flow air sampler as claimed in claim 1, it is characterised in that the blower fan is miniature Wind Volume Blower fan, its a diameter of 140 ± 60mm, rated voltage are 5～24V, and rated current is 0.3～6A, and air quantity is 30～300CFM.

5. Portable high-flow air sampler as claimed in claim 1, it is characterised in that the collection pipeline is reducing type Collection pipeline, it is the less air inlet of bore to install humidification sampling head one end；Connecting fan one end is the larger air outlet of bore.

6. Portable high-flow air sampler as claimed in claim 5, it is characterised in that the material of the collection pipeline is Metal or plastics, inwall are polytetrafluorethylecoatings coatings, and air inlet internal diameter is 10～100mm, and air outlet internal diameter is 80～200mm.

7. Portable high-flow air sampler as claimed in claim 1, it is characterised in that in collection pipeline near blower fan one The crosscutting processing of the side wall at end formed one can outside Unscrew semicircular cylinder, the semicircular cylinder and parent pipeline one end gemel connection, Other end lock connection.

8. Portable high-flow air sampler as claimed in claim 6, it is characterised in that support frame as described above is a supporting bracket Disk, its side are fixedly connected with the inwall of the semicircular cylinder by screw.

9. Portable high-flow air sampler as claimed in claim 1, it is characterised in that the humidification sampling head is arranged on Collection pipeline air inlet, is ring-like pipe-like, and the atomizing piece being internally provided with for ultrasonic atomizatio, inner wall lower correspond to layout Water smoke spray orifice, sonic oscillation make the aseptic water atomization in pipeline and spray through water smoke spray orifice, mix with the air for entering collection pipeline Close.

10. Portable high-flow air sampler as claimed in claim 1, it is characterised in that the sampling media is solid Culture medium or not volatile liquid；The battery is lithium ion chargeable battery；The circuit control module is single-chip microcomputer control Circuit processed.