Exhaled breath detection unit and detection method

Abstract

This invention provides an exhaled breath detection unit and detection method, relating to the field of gas concentration detection technology. The exhaled breath detection unit provided by this invention, through the setting of a first gas path, can improve the ozone production effect of the ozone generation device, ensuring the concentration of ozone produced, while also effectively reducing the moisture content of ozone-containing gas entering the reaction end, avoiding its impact on the chemiluminescence reaction and improving detection accuracy. Through the pump position and pipeline design, only one pump is needed to effectively control the function of each gas path in the detection unit. The setting of a second gas path purges the PMT end, preventing condensation from damaging the PMT and extending the effective service life of the equipment.

Description

Technical Field

[0001] This invention relates to the field of gas concentration detection technology, and in particular to an exhaled breath detection unit and detection method. Background Technology

[0002] NO gas, as a signaling molecule, plays an important role in multiple systems of the human body. By detecting the concentration of NO in human exhaled air, the nature and degree of airway inflammation can be determined, assisting in the treatment of asthma and predicting the response to pulmonary hypertension. Therefore, the detection of exhaled NO concentration is of great significance for clinical diagnosis, disease development, and monitoring of treatment efficacy.

[0003] In recent years, many methods for detecting NO gas have been developed, including electrochemical methods, laser spectroscopy, and gas condensation methods. However, none of these methods can achieve high precision, high sensitivity, and rapid response for NO gas detection. Chemiluminescence detection works by reacting NO with O3 to generate excited-state NO*2. When the excited-state NO*2 transitions back to the ground state, it releases energy and emits photons. The emitted light has a bandwidth of approximately 600-3000 nm, forming a continuous spectrum with a peak wavelength of 1200 nm. Under conditions of excess O3 concentration, the NO concentration is linearly correlated with the light signal. The light signal generated by the reaction is converted into an electrical signal by a photodetector. The resulting electrical signal undergoes a series of processing steps, including amplification and filtering, before being displayed by an electronic device. Compared to other detection methods, chemiluminescence detection offers advantages such as high precision, high sensitivity, and fast response time for NO.

[0004] The precision and accuracy of chemiluminescence detection are affected by a variety of factors. In the existing structure, insufficient ozone gas concentration and excessive vapor partial pressure entering the chemiluminescence reaction end are important factors affecting the detection results.

[0005] In view of this, the present invention is hereby proposed. Summary of the Invention

[0006] The primary objective of this invention is to provide an exhaled breath detection unit that improves gas detection accuracy through gas path improvements, and features a simple structure and high functional integration, thereby solving at least one of the aforementioned problems.

[0007] The second objective of this invention is to provide a method for detecting exhaled air.

[0008] In a first aspect, the present invention provides an exhaled air detection unit, comprising: an ozone gas path, an air inlet path, an air outlet path, a detection module, a pump, and a first gas path;

[0009] The detection module includes a reaction module and a photomultiplier tube. The reaction module is used to perform a chemiluminescence reaction, and the photomultiplier tube is used to capture the photons generated by the reaction module.

[0010] The air intake passage is used to supply the reaction module with gas containing at least human exhaled air;

[0011] The exhaust passage is used to discharge the waste gas from the reaction module;

[0012] The pump is used to drive the flow of gas in each air path of the exhaled breath detection unit;

[0013] The ozone gas circuit is used to supply the reaction module with a gas containing at least ozone;

[0014] An ozone generator and an ozone preparation device are installed in the ozone gas circuit. The ozone generator is located upstream of the ozone preparation device. The ozone generator includes an inner tube and an outer tube, and the inner tube is connected to the ozone gas circuit.

[0015] The inlet of the first gas path is located in the ozone gas path between the permeation dryer and the ozone preparation device, and the outlet of the first gas path is connected to the inlet of the outer tube of the permeation dryer; the outlet of the outer tube of the permeation dryer is connected to the pump.

[0016] As a further technical solution, a first flow limiter is provided in the first air passage to limit the flow rate of dry air passing through the first air passage.

[0017] As a further technical solution, a second gas path is also included. The inlet of the second gas path is connected to the ozone gas path between the permeation dryer and the ozone preparation device, and the outlet of the second gas path is connected to the photomultiplier tube of the detection module.

[0018] As a further technical solution, an air filter and a first flow meter are also provided in the ozone gas path. The air filter is located upstream of the permeation dryer, and the first flow meter is located upstream of the ozone preparation device to monitor the gas flow rate entering the ozone preparation device.

[0019] As a further technical solution, a second flow limiter is provided in the second air passage to limit the flow rate of dry air passing through the second air passage;

[0020] A third flow limiter is also installed on the ozone gas circuit to limit the flow rate of ozone-containing gas entering the reaction module.

[0021] As a further technical solution, the flow rate range that the first flow limiter allows the gas to pass through is 50 to 300 ml / min;

[0022] The second flow limiter allows gas to pass through in a flow range of 50–300 ml / min;

[0023] The third flow limiter allows a gas flow rate of 50–100 ml / min.

[0024] As a further technical solution, an exhaust gas processor is also provided on the exhaust passage.

[0025] As a further technical solution, an exhaust passage is also included; the air inlet of the exhaust passage is connected to the photomultiplier tube, and the air outlet of the exhaust passage is connected to the exhaust passage.

[0026] As a further technical solution, the pump is installed on the air outlet passage;

[0027] The outlet of the outer tube of the permeation dryer is connected to the outlet passage upstream of the pump.

[0028] The exhaust gas processor is located on the exhaust passage upstream of the pump;

[0029] The exhaust port of the exhaust passage is connected to the exhaust passage upstream of the pump.

[0030] As a further technical solution, the air intake passage is also equipped with a second flow meter and a fourth flow limiter. The second flow meter is used to monitor the flow rate of the gas containing human exhaled gas entering the reaction module, and the fourth flow limiter is used to restrict the flow rate of the gas containing human exhaled gas entering the reaction module. The fourth flow limiter allows the gas to pass through at a flow rate of 250-400 ml / min.

[0031] As a further technical solution, a calibration gas path is also included for periodically calibrating the monitoring module; the calibration gas path is connected to the air intake path; the calibration gas path is sequentially provided with a standard gas inlet, a pressure reducing valve, a first solenoid valve and a fifth flow limiter, and a standard gas exhaust port is opened on the calibration gas path downstream of the fifth flow limiter to discharge excess standard gas.

[0032] As a further technical solution, the detection module also includes an insulation chamber, a heat dissipation module, and a heat preservation chamber;

[0033] The reaction module includes a first inlet pipe, a second inlet pipe, an outlet pipe, a premixing chamber, a reaction chamber, and a filter. One end of the first inlet pipe is connected to the premixing chamber for introducing reaction gas into the premixing chamber, and the other end is connected to the ozone gas path. One end of the second inlet pipe is connected to the premixing chamber for introducing the gas to be tested into the premixing chamber, and the other end is connected to the inlet passage. One end of the outlet pipe is connected to the reaction chamber for discharging the gas in the reaction chamber, and the other end is connected to the outlet passage. One end of the reaction chamber is connected to the premixing chamber, and the other end is open. The filter is disposed at the open end of the reaction chamber.

[0034] The volume of the premixing chamber is 2 to 10 cubic centimeters;

[0035] The heat insulation chamber includes a heat insulation box and a photomultiplier tube fixed inside the heat insulation box; the photomultiplier tube is located on the side of the filter away from the reaction chamber and is used to receive filtered photons; the heat insulation box is used to reduce the transfer of heat from the reaction module to the photomultiplier tube;

[0036] The heat dissipation module is used for heat dissipation of the photomultiplier tube;

[0037] The reaction module and the insulation chamber are located inside the insulation chamber to maintain a stable temperature within the reaction module and the insulation chamber.

[0038] Secondly, the present invention provides an exhaled air detection method, based on the above-mentioned exhaled air detection unit, comprising the following steps:

[0039] Exhaled air input: Driven by the pump, the collected exhaled air enters the air intake passage and enters the reaction module of the detection module at a constant flow rate;

[0040] Ozone input: Driven by the pump, air enters the ozone circuit, is filtered by the air filter, and then enters the inner tube of the permeation dryer for drying. The dried air after passing through the permeation dryer enters the ozone preparation device, where the O2 in the dried air is converted into O3. Then, after passing through the third flow limiter, it enters the reaction module of the detection module.

[0041] Backflow purging: The dried air after passing through the permeate dryer also flows back to the outer tube of the permeate dryer through the first air path driven by the pump.

[0042] Drying and purging: The dried air after passing through the permeation dryer is also transmitted to the photomultiplier tube through a second air path driven by a pump for purging;

[0043] Exhaust: The exhaust gas from the reaction module is discharged through the outlet of the reaction module and enters the exhaust passage under the drive of the pump. After being processed by the exhaust gas processor, it is pumped and finally discharged from the outlet. The reflux purging gas is discharged through the outlet of the outer tube of the permeate dryer and enters the exhaust passage under the drive of the pump. After being pumped, it is finally discharged from the outlet. The drying purging gas is discharged through the outlet of the photomultiplier tube under the drive of the pump. Then it enters the exhaust passage and enters the exhaust passage. After being pumped, it is finally discharged from the outlet.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] 1. By setting up a first gas path, the present invention can return the gas dried in the inner tube of the dryer to the outer tube of the dryer, thereby effectively improving the drying performance of the dryer, further reducing the moisture content of the gas entering the ozone preparation device, thereby improving the ozone preparation effect of the ozone preparation device, ensuring the concentration of ozone prepared, and also effectively reducing the moisture content of the ozone-containing gas entering the reaction end, avoiding the influence on the chemiluminescence reaction and improving the detection accuracy.

[0046] 2. Through the pump location and pipeline design, this invention allows for the effective execution of the functions of each gas passage in the detection unit to be controlled by only one pump;

[0047] 3. By setting up a second air path, the present invention purges the PMT end, preventing condensate from damaging the PMT and extending the effective service life of the equipment. Attached Figure Description

[0048] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0049] Figure 1 This is a schematic diagram of the gas path distribution of the detection unit in Embodiment 1 of the present invention;

[0050] Figure 2 This is a schematic diagram of the detection unit in Embodiment 1 of the present invention;

[0051] Figure 3 This is a schematic diagram of the gas flow direction in the first gas path of the detection unit in Embodiment 1 of the present invention;

[0052] Figure 4 This is a schematic diagram of the ozone gas path and gas flow direction of the detection unit in Embodiment 1 of the present invention;

[0053] Figure 5 This is a schematic diagram of the gas flow direction in the air inlet and outlet passages of the detection unit in Embodiment 1 of the present invention;

[0054] Figure 6 This is a schematic diagram of the gas flow direction in the calibration gas path and outlet gas path of the detection unit in Embodiment 1 of the present invention;

[0055] Figure 7 This is a schematic diagram of the gas flow direction in the second gas path and exhaust path of the detection unit in Embodiment 1 of the present invention;

[0056] Figure 8 This is a cross-sectional view of the detection module in Embodiment 1 of the present invention;

[0057] Figure 9 for Figure 8 A magnified view of one of the locations;

[0058] Figure 10 This is an exploded view of the detection module in Embodiment 1 of the present invention.

[0059] Icons: 1-Reaction module; 101-First air inlet pipe; 102-Second air inlet pipe; 103-Outlet pipe; 104-Premixing chamber; 105-Reaction chamber; 106-Filter; 107-Filter mounting base; 108-First seal; 109-Second seal; 110-Third seal; 111-Heating device; 112-Thermometer; 2-Insulation chamber; 201-Insulation box; 202-Photomultiplier tube; 203-Photomultiplier tube mounting base; 3-Heat dissipation module; 301-Peltier; 302-Heat conduction block; 303-Heat dissipation fin; 304-Flow guide; 305-Fan; 4-Insulation chamber; 401-Insulation box; 402-Insulation box cover; 501 - Base; 502 - Base cover; 6 - Ozone gas path; 601 - Permeation dryer; 602 - Ozone preparation device; 603 - Air filter; 604 - First flow meter; 605 - Third flow restrictor; 7 - Inlet passage; 701 - Second flow meter; 702 - Fourth flow restrictor; 8 - Outlet passage; 801 - Pump; 802 - Waste gas processor; 9 - Detection module; 10 - First gas path; 1001 - First flow restrictor; 11 - Second gas path; 1101 - Second flow restrictor; 12 - Calibration gas path; 1201 - Standard gas inlet; 1202 - Pressure reducing valve; 1203 - First solenoid valve; 1204 - Fifth flow restrictor; 1205 - Standard gas exhaust port; 13 - Exhaust passage. Detailed Implementation

[0060] The embodiments and examples of the present invention will be described in detail below. However, those skilled in the art will understand that the following embodiments and examples are for illustrative purposes only and should not be considered as limiting the scope of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. Unless otherwise specified, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0061] In a first aspect, the present invention provides an exhaled air detection unit, comprising: an ozone gas path 6, an air inlet path 7, an air outlet path 8, a detection module 9, a pump 801, and a first air path 10;

[0062] The detection module 9 includes a reaction module 1 and a photomultiplier tube 202. The reaction module 1 is used to perform a chemiluminescence reaction, and the photomultiplier tube 202 is used to capture the photons generated by the reaction module 1.

[0063] The air intake passage 7 is used to supply gas containing at least human exhaled air to the reaction module 1;

[0064] The exhaust passage 8 is used to discharge the waste gas from the reaction module 1;

[0065] The pump 801 is used to drive the flow of gas in each air path of the exhaled breath detection unit;

[0066] The ozone gas path 6 is used to supply gas containing at least ozone to the reaction module 1;

[0067] The ozone gas path 6 is equipped with a permeation dryer 601 and an ozone preparation device 602. The permeation dryer 601 is located upstream of the ozone preparation device 602 and includes an inner tube and an outer tube, with the inner tube connected to the ozone gas path 6. Air enters through the air inlet, is dried by the dryer, and then enters the ozone preparation device. O2 in the air is converted into O3, and then introduced into the reaction end through the ozone inlet at the reaction end.

[0068] The inlet of the first gas path 10 is located on the ozone gas path 6 between the permeation dryer 601 and the ozone generating device 602. The outlet of the first gas path 10 is connected to the inlet of the outer tube of the permeation dryer 601; the outlet of the outer tube of the permeation dryer 601 is connected to the pump 801. Through this connection method, a pressure difference exists between the inner and outer tubes of the dryer, which meets the operating conditions of the dryer.

[0069] By setting up a first gas path, this invention can improve the ozone production effect of the ozone preparation device, ensure the concentration of ozone produced, and effectively reduce the moisture content of the ozone-containing gas entering the reaction end, thus avoiding the impact on the chemiluminescence reaction and improving the detection accuracy.

[0070] In some preferred embodiments, a first flow limiter 1001 is provided on the first air passage 10 to limit the flow rate of dry air passing through the first air passage 10.

[0071] If a flow limiter is not installed or the flow limiter allows too large a flow rate of gas, the vacuum level of the reaction module will be insufficient (because most of the drying air enters the outer pipe through the first gas path and is then discharged, the vacuum level of other gas paths is insufficient, affecting the gas flow requirements of other gas paths, and the vacuum level at the reaction end is insufficient, so there is not enough ozone-containing air to enter); if the flow limiter allows too small a flow rate of gas, the flow rate of drying air entering the outer pipe will be too small, and the improvement of the drying effect of the dryer will not be significant.

[0072] In some preferred embodiments, a second gas path 11 is also included. The inlet of the second gas path 11 is connected to the ozone gas path 6 between the permeation dryer 601 and the ozone preparation device 602, and the outlet of the second gas path 11 is connected to the photomultiplier tube 202 of the detection module 9. In order to improve the luminous efficiency and achieve the best reaction effect, the reaction module needs to be kept at a constant temperature of 50°C (the temperature of the reaction end can be controlled by electric heating and monitored by a thermometer). At the same time, in order to reduce the dark number of the PMT (photomultiplier tube), the PMT needs to be kept at a constant temperature of 5°C in this solution. Therefore, condensation is easily generated at the PMT end, which will affect the effective service life of the PMT. Therefore, a second gas path is designed to purge the PMT end with dry air and thus treat the condensation in time.

[0073] In some preferred embodiments, the ozone gas path 6 is further provided with an air filter 603 and a first flow meter 604. The air filter 603 is located upstream of the permeation dryer 601 and is used to filter particulate matter in the intake air so as not to affect the service life and effect of the structures in the subsequent path. The first flow meter 604 is located upstream of the ozone preparation device 602 and is used to monitor the gas flow rate entering the ozone preparation device 602.

[0074] In some preferred embodiments, a second flow limiter 1101 is provided on the second air passage 11 to limit the flow rate of dry air passing through the second air passage 11.

[0075] If a flow limiter is not installed or the flow limiter allows too large a gas flow rate, the vacuum level of the reaction module will be insufficient (because most of the drying air passes through the second gas path and is then exhausted, the vacuum level of other gas paths is insufficient, affecting the gas flow requirements of other gas paths, and the vacuum level at the reaction end is insufficient, so there is not enough ozone-containing air to enter); if the flow limiter allows too small a gas flow rate, the flow rate of drying air entering the second gas path will be too small, and the drying effect on the PMT will not be obvious.

[0076] The ozone gas path 6 is also equipped with a third flow limiter 605, which is used to limit the flow rate of ozone-containing gas entering the reaction module 1.

[0077] If the allowed flow rate is too high, it will dilute the NO concentration in the exhaled air entering the reaction end, resulting in a lower actual detection concentration; if the allowed flow rate is too low, it will result in insufficient contact between O3 and exhaled air, which may lead to incomplete reaction and inaccurate detection.

[0078] In some preferred embodiments, the flow rate allowed by the first flow limiter 1001 is 50–300 ml / min.

[0079] The second flow limiter 1101 allows the gas to pass through in a flow range of 50 to 300 ml / min;

[0080] The third flow limiter 605 allows a gas flow rate of 50-100 ml / min.

[0081] This invention further optimizes and adjusts the flow rate of gas allowed by the first, second, and third flow limiters, so that the gas flow rate is controlled within a suitable range, ensuring the normal operation of each gas path while improving detection accuracy.

[0082] In some preferred embodiments, an exhaust gas processor 802 is also provided on the exhaust passage 8; the exhaust gas processor 802 is located upstream of the pump 801, and its main purpose is to treat the ozone in the gas discharged from the reaction end to avoid pollution, and at the same time to prevent ozone from causing corrosion or other damage to the internal structure of the pump 801 and affecting the service life of the pump 801.

[0083] In some preferred embodiments, an exhaust passage 13 is also included; the air inlet of the exhaust passage 13 is connected to the photomultiplier tube 202, and the air outlet of the exhaust passage 13 is connected to the exhaust passage 8.

[0084] In some preferred embodiments, the pump 801 is located on the air outlet passage 8;

[0085] The air outlet of the outer tube of the permeation dryer 601 is connected to the air outlet passage 8 upstream of the pump 801.

[0086] The exhaust gas processor 802 is located on the exhaust passage 8 upstream of the pump 801;

[0087] The exhaust port of the exhaust passage 13 is connected to the exhaust passage 8 upstream of the pump 801. The exhaust passage of the present invention enables the pump to control the gas flow in the second gas passage and the exhaust passage, eliminating the need to design a new gas drive component.

[0088] In this solution, the flow of gas in each path mainly relies on the operation of pumps to create negative pressure in each gas path, thereby driving the corresponding gas flow. Through the pump placement, this invention requires only one pump to ensure the gas flows as needed in each gas path (ozone gas path, inlet path, outlet path, first gas path, second gas path), eliminating the need for multiple pumps, saving costs, and achieving higher system integration.

[0089] The exhaled breath detection unit has high requirements for detection accuracy, and the accurate control of the flow rate of each air path in the system has a great impact on the detection accuracy. The pump position layout of this invention, together with the setting of each flow limiter, enables a single pump to meet the flow control required by each air path when it is running.

[0090] In some preferred embodiments, the air intake passage 7 is further provided with a second flow meter 701 and a fourth flow limiter 702. The second flow meter 701 is used to monitor the flow rate of the gas containing human exhaled air entering the reaction module 1, and the fourth flow limiter 702 is used to limit the flow rate of the gas containing human exhaled air entering the reaction module 1. The fourth flow limiter 702 allows the gas to pass through at a flow rate of 250-400 ml / min.

[0091] In some preferred embodiments, a calibration gas path 12 is also included for periodically calibrating the monitoring module; the calibration gas path 12 is connected to the air intake passage 7; the calibration gas path 12 is provided with a standard gas inlet 1201, a pressure reducing valve 1202, a first solenoid valve 1203 and a fifth flow limiter 1204 in sequence, and a standard gas exhaust port 1205 is opened on the calibration gas path 12 downstream of the fifth flow limiter 1204 for discharging excess standard gas.

[0092] Under the action of pressure reducing valve 1202, fifth flow limiter 1204, and fourth flow limiter 702, the standard gas entering reaction module 1 is kept at constant pressure and constant flow, ensuring the effectiveness of standard gas calibration.

[0093] In some preferred embodiments, such as Figures 8-10 As shown, the detection module 9 also includes an insulation chamber 2, a heat dissipation module 3, and a heat preservation chamber 4;

[0094] The reaction module 1 includes a first inlet pipe 101, a second inlet pipe 102, an outlet pipe 103, a premixing chamber 104, a reaction chamber 105, and a filter 106. One end of the first inlet pipe 101 is connected to the premixing chamber 104 for introducing reaction gas into the premixing chamber 104, and the other end is connected to the ozone gas path 6. One end of the second inlet pipe 102 is connected to the premixing chamber 104 for introducing the gas to be tested into the premixing chamber 104, and the other end is connected to the inlet passage 7. One end of the outlet pipe 103 is connected to the reaction chamber 105 for discharging the gas in the reaction chamber 105, and the other end is connected to the outlet passage 8. One end of the reaction chamber 105 is connected to the premixing chamber 104, and the other end is open. The filter 106 is disposed at the open end of the reaction chamber 105 for filtering out stray light after the luminescence reaction.

[0095] The volume of the premixing chamber 104 is 2 to 10 cubic centimeters. This design does not have special requirements for the shape of the premixing chamber; for example, it can be cylindrical, prismatic, pyramidal, or conical. The inventors have found that the shape design of the premixing chamber has little impact on improving detection accuracy and precision. The main influencing factor is the size of the premixing chamber. If the volume is too large, the two gases cannot effectively contact each other, affecting reaction efficiency; if the volume is too small, the gas residence time is short, and the gas will escape through the exhaust passage, resulting in insufficient mixing.

[0096] The heat insulation chamber 2 includes a heat insulation box 201 and a photomultiplier tube 202 fixed inside the heat insulation box 201; the photomultiplier tube 202 is disposed on the side of the filter 106 away from the reaction chamber 105, and is used to receive filtered photons; the heat insulation box 201 is used to reduce the transfer of heat from the reaction module 1 to the photomultiplier tube 202.

[0097] The heat dissipation module 3 is used for heat dissipation of the photomultiplier tube 202.

[0098] The reaction module 1 and the heat insulation chamber 2 are located inside the heat preservation chamber 4 and are used to maintain the temperature stability inside the reaction module 1 and the heat insulation chamber 2.

[0099] This invention, through its reaction chamber structure design (premixing chamber + reaction chamber), enables a more complete reaction, thereby improving detection accuracy and precision. The reaction chamber structure design can also be further coordinated with the temperature control structure (insulation chamber, heat dissipation module, and insulation chamber) design, allowing for precise control of the high temperature of the reaction module and the low temperature of the PMT. This not only further enhances the reaction effect within the reaction module but also ensures that the PMT operates under optimal conditions, improving the efficiency of light signal collection and conversion.

[0100] In some preferred embodiments, the position where the exhaust pipe 103 communicates with the reaction chamber 105 is far away from the position where the first intake pipe 101 and the second intake pipe 102 communicate with the premixing chamber.

[0101] Connect the exhaust pipe to a location far from the intake pipe to prevent the intake air from being discharged through the exhaust pipe before it has fully reacted, which could affect the test results.

[0102] In some preferred embodiments, the volume of the premixing chamber 104 is smaller than that of the reaction chamber 105.

[0103] In some preferred embodiments, the inner surface of the reaction chamber 105 is plated with gold.

[0104] The gold plating design increases the efficiency of light signal collection and the corrosion resistance of the reaction chamber, thereby extending the effective service life of the detection unit.

[0105] In some preferred embodiments, the reaction module 1 further includes a filter mounting base 107;

[0106] The filter mounting base 107 is located at the open end of the reaction chamber 105 and has mounting holes for fixing the filter 106.

[0107] In some preferred embodiments, the reaction module 1 further includes a first seal 108, a second seal 109, and a third seal 110.

[0108] The first sealing element 108 is disposed between the reaction chamber 105 and the filter 106 to ensure airtightness and prevent gas from escaping from the gap between the reaction module 1 and the filter 106, thus affecting the detection accuracy.

[0109] The second sealing element 109 is disposed between the reaction chamber 105 and the filter mounting base 107; the third sealing element 110 is disposed between the heat insulation chamber 2 and the filter mounting base 107. The second sealing element 109 and the third sealing element 110 are used to ensure light tightness, prevent light leakage between the reaction chamber 105 and the filter 106, and between the filter 106 and the photomultiplier tube 202, and ensure that the photomultiplier tube 202 is not affected by environmental interference. Light leakage will also affect the detection accuracy and precision.

[0110] The sealed structure design ensures airtightness and light tightness, avoiding environmental interference with the detection module and improving detection accuracy and precision.

[0111] In some preferred embodiments, the reaction module 1 further includes a heating device 111 for heating the reaction module 1.

[0112] The temperature of the reaction module is maintained at 50°C by heating.

[0113] In some preferred embodiments, the heat insulation chamber 2 further includes a photomultiplier tube mounting base 203;

[0114] The photomultiplier tube 202 is installed in the photomultiplier tube mounting base 203.

[0115] In some preferred embodiments, the heat dissipation module 3 includes a Peltier 301, a heat-conducting block 302, a heat sink 303, a shroud 304, and a fan 305;

[0116] The heat insulation box 201 is provided with an opening, and a Peltier 301 is installed at the opening. One side of the Peltier 301 is attached to the outside of the photomultiplier tube mounting base 203, and the other side of the Peltier 301, the heat-conducting block 302 and the heat sink 303 are connected in sequence.

[0117] A flow guide shroud 304 is installed on the outside of the heat sink 303, and a fan 305 is provided at one end of the flow guide shroud 304 for heat dissipation of the heat sink 303.

[0118] In some preferred embodiments, the insulated enclosure is made of a material with low thermal conductivity (e.g., POM (polyoxymethylene)).

[0119] To improve luminous efficiency and achieve optimal reaction results, the reaction chamber 105 needs to be maintained at a constant temperature of 50°C. Simultaneously, to reduce the dark number of the photomultiplier tube 202, it needs to be maintained at a constant temperature of 5°C. Since the reaction chamber 105 and the photomultiplier tube 202 are very close (increasing the distance reduces light signal collection), heat transfer is likely to occur, making it difficult to maintain constant temperatures for both parts. Therefore, an insulation structure was designed. The insulation chamber 2, made of a low thermal conductivity material, directly contacts the reaction module 1 during assembly. A heat dissipation module is also installed, which significantly reduces high-temperature transfer at the reaction chamber 105. Furthermore, to avoid the influence of ambient temperature, the outer side is insulated by the insulation chamber 4, effectively maintaining the temperature of both parts at the desired values.

[0120] In some preferred embodiments, the insulation chamber 4 includes an insulation box body 401 and an insulation box body cover 402.

[0121] In some preferred embodiments, the insulation chamber 4 is made of NBR insulation cotton.

[0122] In some preferred embodiments, a base 501 and a base cover 502 are also included;

[0123] The insulated chamber 4 is located inside the base 501.

[0124] Secondly, the present invention provides an exhaled air detection method, based on the above-mentioned exhaled air detection unit, comprising the following steps:

[0125] Exhaled air input: Driven by pump 801, the collected exhaled air enters the air intake passage 7 and enters the reaction module 1 of the detection module 9 at a constant flow rate;

[0126] Ozone input: Driven by pump 801, air enters ozone path 6, is filtered by air filter 603 and then enters the inner tube of permeation dryer 601 for drying. The dried air after passing through permeation dryer 601 enters ozone preparation device 602, where O2 in the dried air is converted into O3. Then, after passing through third flow limiter 605, it enters reaction module 1 of detection module 9.

[0127] Backflow purging: The dried air after passing through the permeate dryer 601 also flows back to the outer tube of the permeate dryer 601 through the first air passage 10 under the drive of the pump 801.

[0128] Drying and purging: The dried air after passing through the permeation dryer 601 is also transmitted to the photomultiplier tube 202 through the second air passage 11 under the drive of the pump 801 for purging;

[0129] Exhaust gas: The exhaust gas after the reaction in reaction module 1 is discharged through the outlet of reaction module 1 and enters the exhaust passage 8 under the drive of pump 801. After being processed by exhaust gas processor 802, it is discharged through pump 801 and finally discharged from the outlet. The backflow purging gas is discharged through the outlet of the outer tube of the permeate dryer 601 and enters the exhaust passage 8 under the drive of pump 801. After passing through pump 801, it is finally discharged from the outlet. The drying purging gas is discharged through the outlet of photomultiplier tube 202 under the drive of pump 801, then enters the exhaust passage 8 through exhaust passage 13, passes through pump 801, and finally discharges from the outlet.

[0130] The detection method provided by this invention is simple in process and highly accurate.

[0131] The present invention will be further illustrated below with specific embodiments. However, it should be understood that these embodiments are merely for the purpose of more detailed illustration and should not be construed as limiting the present invention in any way.

[0132] Example 1

[0133] An exhaled breath detection unit, such as Figure 1 and Figure 2 As shown, it includes: ozone gas path 6, air inlet path 7, air outlet path 8, detection module 9, first gas path 10, second gas path 11, calibration gas path 12 and exhaust path 13;

[0134] Along the air intake direction, the ozone gas path 6 is sequentially equipped with: an air filter 603, a permeation dryer 601, a first flow meter 604, an ozone preparation device 602, and a third flow limiter 605; wherein, the permeation dryer 601 includes an inner tube and an outer tube, the inner tube being connected to the ozone gas path 6; the third flow limiter 605 is connected to the first air intake pipe 101 of the reaction module 1, allowing the gas flow rate to pass through to be 70-100 ml / min;

[0135] Along the air intake direction, a second flow meter 701 and a fourth flow limiter 702 are sequentially installed on the air intake passage 7; the fourth flow limiter 702 is connected to the second air intake pipe 102 of the reaction module 1.

[0136] Along the exhaust direction, an exhaust gas processor 802 and a pump 801 are sequentially installed on the exhaust passage 8; the exhaust gas processor 802 is connected to the exhaust pipe 103 of the reaction module 1;

[0137] The inlet of the first gas path 10 is located on the ozone gas path 6 between the permeation dryer 601 and the ozone preparation device 602. The outlet of the first gas path 10 is connected to the inlet of the outer tube of the permeation dryer 601. The outlet of the outer tube of the permeation dryer 601 is connected to the outlet passage 8 upstream of the pump 801. A first flow limiter 1001 is provided on the first gas path 10, which allows the gas flow rate to be 50-300 ml / min.

[0138] The inlet of the second gas path 11 is located on the ozone gas path 6 between the permeation dryer 601 and the ozone preparation device 602. The outlet of the second gas path 11 is connected to the photomultiplier tube 202 of the detection module 9 for heat dissipation and condensate treatment of the photomultiplier tube 202. A second flow limiter 1101 is provided on the second gas path 11, allowing the gas flow rate to be 50-300 ml / min.

[0139] Along the air intake direction, the calibration air passage 12 is sequentially provided with a standard gas inlet 1201, a pressure reducing valve 1202, a first solenoid valve 1203 and a fifth flow limiter 1204; the fifth flow limiter 1204 is connected to the air intake passage 7 upstream of the second flow meter 701; a standard gas exhaust port 1205 is opened on the calibration air passage 12 downstream of the fifth flow limiter 1204;

[0140] The air inlet of the exhaust passage 13 is connected to the photomultiplier tube 202, and the air outlet of the exhaust passage 13 is connected to the air outlet passage 8 upstream of the pump 801.

[0141] Detection module 9, such as Figures 8-10 As shown, it includes a reaction module 1, an insulation chamber 2, a heat dissipation module 3, a heat preservation chamber 4, a base 501, and a base cover 502;

[0142] The reaction module 1 is made of aluminum alloy and includes a first inlet pipe 101, a second inlet pipe 102, an outlet pipe 103, a premixing chamber 104, a reaction chamber 105, a filter 106, and a filter mounting base 107. One end of the first inlet pipe 101 is connected to the premixing chamber 104 for introducing the gas to be tested into the premixing chamber 104; one end of the second inlet pipe 102 is connected to the premixing chamber 104 for introducing ozone into the premixing chamber 104; one end of the outlet pipe 103 is connected to the reaction chamber 105 for discharging the gas from the reaction chamber 105; the outlet pipe 103 is connected to the reaction chamber 105. The connection point of the 5th chamber is far from the connection points of the first intake pipe 101, the second intake pipe 102, and the premixing chamber; one end of the reaction chamber 105 is connected to the premixing chamber 104, and the other end is open; the wavelength range of the filter 106 is 700-2600nm; the filter mounting base 107 is located at the open end of the reaction chamber 105 and has a mounting hole, in which the filter 106 is fixed; the premixing chamber 104 is cylindrical in shape, with a diameter of 3mm and a height of 3.5mm, and its volume is smaller than that of the reaction chamber 105; the reaction chamber 105 is hemispherical in shape, with an average gold plating thickness of about 0.5μm and a smooth surface.

[0143] The reaction module 1 also includes a first sealing element 108, a second sealing element 109, a third sealing element 110, and a heating device 111; the first sealing element 108 is disposed between the reaction chamber 105 and the filter 106; the second sealing element 109 is disposed between the reaction chamber 105 and the filter mounting base 107; the third sealing element 110 is disposed between the heat insulation chamber 2 and the filter mounting base 107; the heating device is used for heating the reaction module 1.

[0144] The heat insulation chamber 2 includes a heat insulation box 201, a photomultiplier tube 202, and a photomultiplier tube mounting base 203. The photomultiplier tube 202 is a Japanese Hamamatsu H10682 series (with a wavelength range of 230nm to 870nm), which is located on the side of the filter 106 away from the reaction chamber 105 and is used to receive filtered photons. The photomultiplier tube mounting base 203 is made of 6061-T6 type aluminum alloy and fixes the photomultiplier tube 202 inside the heat insulation box 201. The heat insulation box 201 is made of polyoxymethylene plastic.

[0145] Thermometers 112 are installed in reaction module 1 and insulation chamber 2 respectively, for measuring the temperature of reaction chamber 105 and photomultiplier tube 202.

[0146] The heat dissipation module 3 includes a Peltier 301, a heat-conducting block 302, a heat sink 303, a flow guide 304, and a fan 305. The heat insulation box 201 has an opening, and a Peltier 301 is installed at the opening. One side of the Peltier 301 is attached to the outside of the photomultiplier tube mounting base 203. The other side of the Peltier 301, the heat-conducting block 302, and the heat sink 303 are connected in sequence. A flow guide 304 is installed on the outside of the heat sink 303. A fan 305 is provided at one end of the flow guide 304 for heat dissipation of the heat sink 303.

[0147] The insulation chamber 4 is made of NBR insulation cotton and includes an insulation box 401 and an insulation box cover 402; the reaction module 1 and the heat insulation chamber 2 are located inside the insulation chamber 4 to maintain the temperature stability inside the reaction module 1 and the heat insulation chamber 2.

[0148] The insulated chamber 4 is located inside the base 501.

[0149] The detection principle of the detection module 9 is as follows: Exhaled air and ozone enter the premixing chamber 104 of the reaction module 1 through the first air inlet pipe 101 and the second air inlet pipe 102, respectively. They are mixed in the premixing chamber 104, and then a light-emitting reaction occurs in the reaction chamber 105. The gas is then discharged through the exhaust pipe 103. The light generated by the reaction is filtered by the filter 106 to remove noise and is captured by the photomultiplier tube 202. The NO concentration in the exhaled air can be detected based on the number of photons captured by the photomultiplier tube 202.

[0150] The exhaled breath detection unit shows the gas flow direction in each pathway under the action of the pump as follows: Figures 3-7 As shown, during runtime:

[0151] Exhaled air input: Driven by pump 801, the collected exhaled air enters the air intake passage 7 and enters the reaction module 1 of the detection module 9 at a constant flow rate; the fourth flow limiter in this embodiment allows the gas to pass through at a flow rate of 330 ml / min.

[0152] Ozone Input: Driven by pump 801, air enters ozone gas path 6. After passing through air filter 603 to filter particles larger than 5μm, the air enters the inner tube of permeation dryer 601. Under the pressure difference between the inner and outer tubes, water vapor permeates from the inner tube wall to the outer tube. The dried air after passing through permeation dryer 601 enters ozone preparation device 602. O2 in the dried air entering ozone preparation device 602 is converted into O3. After passing through third flow limiter 605, it enters reaction module 1 of detection module 9. The third flow limiter 605 allows the gas flow rate to be 90ml / min.

[0153] Backflow purging: The dried air after passing through the permeate dryer 601 is also returned to the outer tube of the permeate dryer 601 through the first gas path 10 driven by the pump 801. The first flow limiter 1001 of the first gas path 10 allows the gas flow rate to be 70 ml / min.

[0154] Drying and purging: The dried air after passing through the permeation dryer 601 is also transmitted to the photomultiplier tube 202 through the second gas path 11 driven by the pump 801 for purging. The second flow limiter 1101 of the second gas path 11 allows the gas flow rate to be 70 ml / min.

[0155] Exhaust gas: The exhaust gas after the reaction in reaction module 1 is discharged through the outlet of reaction module 1 under the drive of pump 801. After being processed by exhaust gas processor 802, it is discharged from the outlet after passing through pump 801.

[0156] The refluxed purging gas is discharged from the outlet of the outer tube of the permeate dryer 601 under the drive of pump 801, and finally discharged from the outlet after passing through pump 801.

[0157] Driven by pump 801, the dried purging gas is discharged from the outlet of photomultiplier tube 202, passes through exhaust passage 13, exhaust gas processor 802, and pump 801, and is finally discharged from the outlet.

[0158] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An exhaled breath detection unit, characterized in that, include: Ozone gas path (6), air inlet path (7), air outlet path (8), detection module (9), pump (801) and first gas path (10); The detection module (9) includes a reaction module (1) and a photomultiplier tube (202). The reaction module (1) is used to perform a chemiluminescence reaction, and the photomultiplier tube (202) is used to capture the photons generated by the reaction module (1). The air intake passage (7) is used to supply the reaction module (1) with gas containing at least human exhaled air; The exhaust passage (8) is used to discharge the waste gas from the reaction module (1); The pump (801) is used to drive the flow of gas in each air path of the exhaled breath detection unit; The ozone gas path (6) is used to supply gas containing at least ozone to the reaction module (1); An ozone gas path (6) is provided with a permeation dryer (601) and an ozone preparation device (602). The permeation dryer (601) is located upstream of the ozone preparation device (602). The permeation dryer (601) includes an inner tube and an outer tube. The inner tube is connected to the ozone gas path (6). The inlet of the first gas path (10) is located on the ozone gas path (6) between the permeation dryer (601) and the ozone preparation device (602), and the outlet of the first gas path (10) is connected to the inlet of the outer tube of the permeation dryer (601); the outlet of the outer tube of the permeation dryer (601) is connected to the pump (801). A first flow limiter (1001) is provided on the first air passage (10) to limit the flow rate of dry air passing through the first air passage (10); It also includes a second gas path (11), the inlet of which is connected to the ozone gas path (6) between the permeation dryer (601) and the ozone preparation device (602), and the outlet of the second gas path (11) is connected to the photomultiplier tube (202) of the detection module (9).

2. The exhaled breath detection unit according to claim 1, characterized in that, An air filter (603) and a first flow meter (604) are also provided on the ozone gas path (6). The air filter (603) is located upstream of the permeation dryer (601), and the first flow meter (604) is located upstream of the ozone preparation device (602) to monitor the gas flow rate entering the ozone preparation device (602).

3. The exhaled breath detection unit according to claim 2, characterized in that, A second flow limiter (1101) is provided on the second air passage (11) to limit the flow rate of dry air through the second air passage (11); The ozone gas path (6) is also equipped with a third flow limiter (605) to limit the flow rate of ozone-containing gas entering the reaction module (1).

4. The exhaled breath detection unit according to claim 3, characterized in that, The first flow limiter (1001) allows a gas flow rate of 50~300ml / min. The second flow limiter (1101) allows a gas flow rate of 50~300ml / min. The third flow limiter (605) allows a gas flow rate of 50~100 ml / min.

5. The exhaled breath detection unit according to claim 4, characterized in that, An exhaust gas processor (802) is also provided on the exhaust passage (8).

6. The exhaled breath detection unit according to claim 5, characterized in that, It also includes an exhaust passage (13); the air inlet of the exhaust passage (13) is connected to the photomultiplier tube (202), and the air outlet of the exhaust passage (13) is connected to the exhaust passage (8).

7. The exhaled breath detection unit according to claim 6, characterized in that, The pump (801) is located on the air outlet passage (8); The outlet of the outer tube of the permeation dryer (601) is connected to the outlet passage (8) upstream of the pump (801); The exhaust gas processor (802) is located on the exhaust passage (8) upstream of the pump (801); The outlet of the exhaust passage (13) is connected to the exhaust passage (8) upstream of the pump (801).

8. The exhaled breath detection unit according to any one of claims 1 to 7, characterized in that, The air intake passage (7) is also equipped with a second flow meter (701) and a fourth flow limiter (702). The second flow meter (701) is used to monitor the flow rate of human exhaled gas entering the reaction module (1). The fourth flow limiter (702) is used to limit the flow rate of human exhaled gas entering the reaction module (1). The fourth flow limiter (702) allows the gas to pass through at a flow rate of 250~400ml / min.

9. The exhaled breath detection unit according to any one of claims 1 to 7, characterized in that, It also includes a calibration gas path (12) for periodically calibrating the monitoring module; the calibration gas path (12) is connected to the air intake passage (7); the calibration gas path (12) is provided with a standard gas inlet (1201), a pressure reducing valve (1202), a first solenoid valve (1203) and a fifth flow limiter (1204) in sequence, and a standard gas exhaust port (1205) is opened on the calibration gas path (12) downstream of the fifth flow limiter (1204) for discharging excess standard gas.

10. The exhaled breath detection unit according to claim 1, characterized in that, The detection module (9) also includes an insulation chamber (2), a heat dissipation module (3), and a heat preservation chamber (4); The reaction module (1) includes a first inlet pipe (101), a second inlet pipe (102), an outlet pipe (103), a premixing chamber (104), a reaction chamber (105), and a filter (106); one end of the first inlet pipe (101) is connected to the premixing chamber (104) for introducing reaction gas into the premixing chamber (104), and the other end is connected to the ozone gas path (6); one end of the second inlet pipe (102) is connected to the premixing chamber (105)... 104) is connected to the premixing chamber (104) to introduce the gas to be tested, and the other end is connected to the inlet passage (7); one end of the outlet pipe (103) is connected to the reaction chamber (105) to discharge the gas in the reaction chamber (105), and the other end is connected to the outlet passage (8); one end of the reaction chamber (105) is connected to the premixing chamber (104), and the other end is open; the filter (106) is disposed at the open end of the reaction chamber (105); The volume of the premixing chamber (104) is 2 to 10 cubic centimeters; The heat insulation chamber (2) includes a heat insulation box (201) and a photomultiplier tube (202) fixed inside the heat insulation box (201); the photomultiplier tube (202) is located on the side of the filter (106) away from the reaction chamber (105) and is used to receive filtered photons; the heat insulation box (201) is used to reduce the transfer of heat from the reaction module (1) to the photomultiplier tube (202); The heat dissipation module (3) is used for heat dissipation of the photomultiplier tube (202); The reaction module (1) and the insulation chamber (2) are located inside the insulation chamber (4) to maintain the stability of the temperature inside the reaction module (1) and the insulation chamber (2).

11. A method for detecting exhaled breath, characterized in that, The exhaled air detection unit according to any one of claims 1 to 10 includes the following steps: Exhaled air input: Driven by the pump (801), the collected exhaled air enters the air intake passage (7) and enters the reaction module (1) of the detection module (9) at a constant flow rate; Ozone input: Driven by the pump (801), air enters the ozone gas path (6), is filtered by the air filter (603), and then enters the inner tube of the permeation dryer (601) for drying. The dried air after passing through the permeation dryer (601) enters the ozone preparation device (602) to convert O2 in the dried air into O3. Then, after passing through the third flow limiter (605), it enters the reaction module (1) of the detection module (9). Backflow purging: The dried air after passing through the permeate dryer (601) also flows back to the outer tube of the permeate dryer (601) through the first air passage (10) driven by the pump (801); Drying and purging: The dried air after passing through the permeation dryer (601) is also transmitted to the photomultiplier tube (202) through the second air path (11) driven by the pump (801) for purging; Exhaust gas: The exhaust gas after the reaction of the reaction module (1) is discharged through the outlet of the reaction module (1) and enters the exhaust passage (8) under the drive of the pump (801). After being processed by the exhaust gas processor (802), it is discharged through the pump (801) and finally discharged from the outlet. The gas of the backflow purging is discharged through the outlet of the outer tube of the permeate dryer (601) and enters the exhaust passage (8) under the drive of the pump (801). After passing through the pump (801), it is finally discharged from the outlet. The gas of the drying purging is discharged through the outlet of the photomultiplier tube (202) under the drive of the pump (801). Then it enters the exhaust passage (8) through the exhaust passage (13). After passing through the pump (801), it is finally discharged from the outlet.

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