Low-cost portable FENO concentration detection equipment

Abstract

The invention discloses a low-cost portable FENO concentration detection device which comprises a gas absorption cell, a gas inlet is formed in one end of the gas absorption cell, a sucking pump is arranged at the other end of the gas absorption cell, a broadband light source is connected to the end, close to the gas inlet, of the side face of the gas absorption cell, a spectrograph is connected to the end, close to the sucking pump, of the side face of the gas absorption cell, and a controller is connected to one side of the spectrograph. One side of the controller is connected with a display, and a control system is arranged in the controller; by arranging the gas absorption cell and cooperating with the broadband light source and the spectrograph, the FENO concentration is detected through the ultraviolet differential absorption spectrum, the sensitivity and detection precision are high, the anti-interference performance is high, the FENO concentration can be measured in real time, chemical reaction is not depended, no chemical reagent consumables are used, the long-term use cost of equipment is reduced, and the device is simple and compact in overall structure, small in size and convenient to operate. And compared with traditional monitoring equipment, the convenience is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of equipment, and in particular to a FENO concentration detection device based on ultraviolet differential absorption spectroscopy. Background Art

[0002] Lung diseases (such as lung cancer, bronchitis, lung nodules, etc.) are important public health issues worldwide. With the intensification of industrialization and environmental pollution, the incidence of respiratory diseases has increased year by year. Clinically, early diagnosis and monitoring of lung diseases are usually carried out by imaging methods such as CT and MRI, as well as bronchoscopy. However, these traditional methods have many problems:

[0003] 1. Highly invasive: such as bronchoscopy, which requires invasive operations on patients, may cause infection and discomfort, and is not suitable for frequent use;

[0004] 2. High cost and complexity: Imaging examinations such as CT and MRI are expensive and have complicated testing procedures, making them difficult to apply in primary medical institutions and portable testing scenarios;

[0005] 3. The effect of early detection is limited: Imaging examinations are usually used in the middle and late stages when lung lesions have already appeared, but they are not sensitive enough to microscopic lesions such as early airway inflammation.

[0006] In recent years, exhaled breath analysis has become a research hotspot as a non-invasive detection method. In particular, the concentration detection of exhaled nitric oxide (FENO) has the potential for early diagnosis because it is closely related to airway inflammation. Authoritative organizations such as the U.S. Food and Drug Administration (FDA), the European Respiratory Society (ERS) and the American Thoracic Society (ATS) have successively used FENO as a biomarker for asthma and listed FENO as a routine examination item for respiratory diseases.

[0007] Currently, the widely used FENO detection technologies mainly include the electrochemical sensor method, which uses electrochemical sensors to detect FENO. However, the accuracy and sensitivity of this method are easily affected by the external environment (such as humidity, temperature, etc.), and the service life of the sensor is limited. Usually, a new sensor needs to be replaced in about a year, and it is easily interfered by other gases in the exhaled breath, resulting in deviations in the detection results; the chemiluminescence method, which detects FENO through chemiluminescence reaction, but this method has bulky equipment, complicated operation, and consumes chemical reagents, which is not suitable for portable applications; the fluorescent probe method, which generates a fluorescent signal after a chemical reaction with NO. This method has high detection sensitivity, but requires a specific experimental environment, is cumbersome to operate, and has poor real-time performance, which is not suitable for rapid detection in clinical sites.

[0008] Therefore, the existing detection methods and devices have deficiencies in sensitivity, anti-interference ability, portability and cost. Therefore, the present invention proposes a FENO concentration detection device based on ultraviolet differential absorption spectroscopy to solve the problems existing in the prior art. Summary of the invention

[0009] In view of the above problems, the purpose of the present invention is to propose a FENO concentration detection device based on ultraviolet differential absorption spectroscopy. The FENO concentration detection device based on ultraviolet differential absorption spectroscopy realizes ultraviolet differential absorption spectroscopy detection of FENO concentration by setting a gas absorption cell and cooperating with a broadband light source and a spectrometer. It has high sensitivity and detection accuracy and strong anti-interference ability, is independent of chemical reactions, and has no chemical reagent consumables, thereby reducing the long-term use cost of the equipment. The overall structure of the device is simple and compact, and the size is small, and the convenience is significantly improved compared with traditional monitoring equipment.

[0010] To achieve the purpose of the present invention, the present invention is implemented through the following technical scheme: a FENO concentration detection device based on ultraviolet differential absorption spectroscopy, including a gas absorption cell, an air inlet, an air pump, a broadband light source, a spectrometer, a controller and a display, wherein an air inlet is provided at one end of the gas absorption cell, and an air pump is provided at the other end of the gas absorption cell. A broadband light source is connected to the side of the gas absorption cell near the air inlet end, a spectrometer is connected to the side of the gas absorption cell near the air pump end, a controller is connected to one side of the spectrometer, a display is connected to one side of the controller, and the controller has a built-in control system.

[0011] A further improvement is that the control system includes a driving circuit module, a data acquisition module and a microprocessor, the driving circuit module is used to control the drive control of the vacuum pump, the broadband light source and the spectrometer, the data acquisition module is used to collect the spectroscopic detection data in the spectrometer, and the microprocessor processes and analyzes the collected data based on the differential absorption spectroscopy method and gives the concentration of NO in the exhaled breath.

[0012] A further improvement is that the driving circuit module includes an air pump control submodule, a broadband light source control submodule and a spectrometer control submodule. The air pump control submodule is used for start and stop control of the air pump and control of the air extraction speed. The broadband light source control submodule is used for start and stop control of the broadband light source and control of stability and intensity. The spectrometer control submodule is used for drive control of the spectrometer.

[0013] A further improvement is that a filtering and dehumidifying module is provided at the air inlet position, and the filtering and dehumidifying module is used to filter out water vapor and particulate matter.

[0014] A further improvement is that a temperature sensor is provided in the gas absorption cell, a temperature controller is provided on the gas absorption cell, and the temperature sensor is electrically connected to the temperature controller.

[0015] A further improvement is that a light reflector is arranged in the gas absorption cell, and the light reflector is distributed on the inner wall of the gas absorption cell between the broadband light source interface and the spectrometer interface.

[0016] The beneficial effects of the present invention are as follows: the present invention realizes ultraviolet differential absorption spectrum detection of FENO concentration by setting a gas absorption cell and cooperating with a broadband light source and a spectrometer, with high sensitivity and detection accuracy and strong anti-interference, without relying on chemical reactions and chemical reagent consumables, thus reducing the long-term use cost of the equipment;

[0017] The overall structure of the device is simple and compact, with a small size. Compared with traditional monitoring equipment, its convenience is significantly improved, and the applicable scenarios are also improved. It can realize real-time FENO concentration measurement and is suitable for a wide range of clinical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a structural connection diagram of the device according to Example 1 of the present invention.

[0019] Figure 2 This is a top view and cross-sectional diagram of the distribution structure of the light reflector of the gas absorption cell in Example 1 of the present invention.

[0020] Figure 3 This is a bar graph of the mean FENO concentrations of patients in different disease groups in Example 2 of the present invention.

[0021] Among them: 1. gas absorption cell; 2. air inlet; 3. vacuum pump; 4. broadband light source; 5. spectrometer; 6. controller; 7. display; 8. filter dehumidification module; 9. temperature sensor; 10. temperature controller; 11. light reflector. DETAILED DESCRIPTION

[0022] In order to deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with examples. The examples are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0023] The principle of spectroscopy for measuring exhaled breath gas concentration is to use the Beer-Lambert law. When a light beam is transmitted in a medium, it is weakened due to interaction with the substance. The absorbance expression is:

[0024]

[0025] Where I0 is the incident light intensity, I t is the transmitted light intensity, T is the transmitted light intensity, K is the absorption coefficient, L is the thickness of the absorbing medium, and C is the concentration of the gas to be measured.

[0026] The absorption coefficient of gas molecules is a function of the absorption wavelength and is independent of the incident light intensity and the thickness of the medium. According to the Beer-Lambert law, if the absorption coefficient of the measured gas is known, the concentration of the gas can be calculated by measuring the incident light intensity, the transmitted light intensity and the gas thickness.

[0027] The advantage of differential absorption spectroscopy (DOAS) is that by separating the "fast-changing" and "slow-changing" parts of the absorption spectrum, it can effectively eliminate broadband extinction factors caused by Rayleigh scattering, Mie scattering and other gases; specifically, the slow-changing part is mainly caused by Rayleigh scattering and Mie scattering, which change slowly with wavelength, while the fast-changing part is the characteristic absorption of the gas to be tested. By extracting the fast-changing signal, DOAS technology can accurately identify the characteristic absorption of NO, while effectively eliminating background interference, ensuring the stability and reliability of the detection results.

[0028] Example 1

[0029] according to Figure 1 and Figure 2 As shown, this embodiment provides a FENO concentration detection device based on ultraviolet differential absorption spectroscopy, including a gas absorption cell 1, an air inlet 2, an air pump 3, a broadband light source 4, a spectrometer 5, a controller 6 and a display 7. The gas absorption cell 1 is provided with an air inlet 2 at one end, and an air pump 3 is provided at the other end of the gas absorption cell 1. The side of the gas absorption cell 1 near the air inlet 2 is connected to the broadband light source 4, and the side of the gas absorption cell 1 near the air pump 3 is connected to the spectrometer 5. The spectrometer 5 is connected to the controller 6 on one side, and the controller 6 is connected to the display 7 on one side for displaying waveforms and measurement results. The controller 6 has a built-in control system.

[0030] The gas absorption cell is used for the absorption of the gas molecules to be tested and the incident light; the broadband light source uses a deuterium lamp, which can cover multiple absorption bands and is suitable for detecting multiple components in human exhaled breath; the spectrometer is responsible for splitting and detecting the outgoing light of the gas absorption cell, using differential absorption spectroscopy (DOAS) technology, decomposing the ultraviolet spectrum through an interferometer, and using a differential absorption algorithm to analyze the spectral data, which is suitable for multi-component gas analysis.

[0031] The control system includes a driving circuit module, a data acquisition module and a microprocessor. The driving circuit module is used to control the driving of the vacuum pump 3, the broadband light source 4 and the spectrometer 5. The data acquisition module is used to collect the spectroscopic detection data in the spectrometer 5. The microprocessor processes and analyzes the collected data based on the differential absorption spectroscopy method and gives the concentration of NO in the exhaled air.

[0032] The driving circuit module includes an air pump control submodule, a broadband light source control submodule and a spectrometer control submodule. The air pump control submodule is used for start and stop control of the air pump 3 and control of the air extraction speed, and can control the gas flow rate. The broadband light source control submodule is used for start and stop control of the broadband light source 4 and control of stability and intensity. The spectrometer control submodule is used for drive control of the spectrometer 5.

[0033] A filtering and dehumidifying module 8 is provided at the air inlet 2, and the filtering and dehumidifying module 8 is used to filter out water vapor and particulate matter.

[0034] A temperature sensor 9 is provided in the gas absorption cell 1 , and a temperature controller 10 is provided on the gas absorption cell 1 . The temperature sensor 9 is electrically connected to the temperature controller 10 .

[0035] The gas absorption cell 1 is provided with a light reflector 11, which is distributed on the inner wall of the gas absorption cell 1 between the interface of the broadband light source 4 and the interface of the spectrometer 5. Multiple reflections are adopted to increase the optical path. The incident light after multiple reflections not only allows the gas molecules to absorb its energy more fully, but also can well improve the detection lower limit and enhance the detection sensitivity.

[0036] Example 2

[0037] This embodiment conducts an experimental application of the device, and uses the device to measure the actual FENO concentration in a hospital. The samples cover patients with common lung diseases such as lung cancer, tuberculosis, and bronchitis. A total of 64 samples were collected, including 37 males and 27 females. The selection and exclusion criteria are shown in Table 1 below.

[0038] Table 1 Patient selection and exclusion criteria

[0039] Selection criteria Exclusion criteria Age ≥ 18 years Patients with impaired expiratory function who are unable to collect samples Complete routine ventilation pulmonary function tests No cognitive and behavioral abilities Strictly follow sampling requirements Eat after 22:00 the night before, and brush your teeth before eating in the morning Do not eat or drink for 3 hours before the test No nebulizer inhalation therapy 1 hour before the test

[0040] The patients were classified into malignant tumors (adenocarcinoma, lung cancer, esophageal cancer), suspected malignant / benign tumors (mediastinal tumors, right lung mass, left lung mass), benign or non-malignant lesions (pulmonary nodules, chest effusion), infectious / inflammatory diseases (bronchitis, lung abscess), and healthy groups. The mean FENO concentrations of patients in different disease groups are shown in the attached manual. Figure 3 shown.

[0041] IBM SPSS Statistic 27 statistical software was used for data analysis and processing. The area under the curve (AUC) of each group was calculated to measure the diagnostic performance of FENO in different diseases. The AUC values ​​of each group are shown in Table 2.

[0042] Table 2 Diagnostic performance of FENO in different diseases

[0043]

[0044] The FENO levels in patients with lung diseases (mean: 25.95 ppb) were significantly higher than those in the healthy group (mean: 13.38 ppb), which is consistent with the characteristics of FENO as a marker of airway inflammation.

[0045] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A FENO concentration detection device based on ultraviolet differential absorption spectroscopy, characterized in that: The invention comprises a gas absorption cell (1), an air inlet (2), an air pump (3), a broadband light source (4), a spectrometer (5), a controller (6) and a display (7); the gas absorption cell (1) is provided with an air inlet (2) at one end, and an air pump (3) at the other end; a side of the gas absorption cell (1) close to the air inlet (2) is connected to a broadband light source (4); a side of the gas absorption cell (1) close to the air pump (3) is connected to a spectrometer (5); one side of the spectrometer (5) is connected to a controller (6); one side of the controller (6) is connected to a display (7); and the controller (6) has a built-in control system.

2. The FENO concentration detection device based on ultraviolet differential absorption spectroscopy according to claim 1, characterized in that: The control system comprises a driving circuit module, a data acquisition module and a microprocessor. The driving circuit module is used to control the driving of the air pump (3), the broadband light source (4) and the spectrometer (5). The data acquisition module is used to collect spectroscopic detection data in the spectrometer (5). The microprocessor processes and analyzes the collected data based on differential absorption spectroscopy and gives the concentration of NO in the exhaled air.

3. The FENO concentration detection device based on ultraviolet differential absorption spectroscopy according to claim 1, characterized in that: The driving circuit module comprises an air pump control submodule, a broadband light source control submodule and a spectrometer control submodule. The air pump control submodule is used for start and stop control of the air pump (3) and control of the air pumping speed. The broadband light source control submodule is used for start and stop control and control of stability and intensity of the broadband light source (4). The spectrometer control submodule is used for drive control of the spectrometer (5).

4. The FENO concentration detection device based on ultraviolet differential absorption spectroscopy according to claim 1, characterized in that: A filtering and dehumidifying module (8) is provided at the air inlet (2), and the filtering and dehumidifying module (8) is used to filter out water vapor and particulate matter.

5. The FENO concentration detection device based on ultraviolet differential absorption spectroscopy according to claim 1, characterized in that: A temperature sensor (9) is provided in the gas absorption cell (1), a temperature controller (10) is provided on the gas absorption cell (1), and the temperature sensor (9) is electrically connected to the temperature controller (10).

6. The FENO concentration detection device based on ultraviolet differential absorption spectroscopy according to claim 1, characterized in that: A light reflector (11) is provided in the gas absorption cell (1), and the light reflector (11) is distributed on the inner wall of the gas absorption cell (1) between the interface of the broadband light source (4) and the interface of the spectrometer (5).

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