A fiber-optic CO2 and O2 concentration rapid acquisition probe

Abstract

The present invention discloses a fiber-optic CO2 and O2 concentration rapid collection probe, comprising a light-emitting part, a light-receiving part and a fiber-optic body; the light-emitting part comprises a first light-emitting element and a second light-emitting element; the fiber-optic body is a hollow cylinder, a glass light-guiding column is provided inside, a protective sleeve is provided outside, and the light-receiving part is provided in the middle of the inner side of the glass light-guiding column; the light-receiving part comprises an elliptical carrier, an oxygen fluorescence sensitive film and a carbon dioxide fluorescence sensitive film; the oxygen fluorescence sensitive film and the carbon dioxide fluorescence sensitive film are attached to the two sides of the elliptical carrier. The present invention can realize real-time ultrafast reaction O2 and CO2 measurement signal sampling; and can directly convert ultrafast reaction O2 and CO2 measurement light-sensitive signals into electrical signals, reducing the measurement time delay error; at the same time, it directly avoids the sampling time delay caused by the need for a micropump in the traditional CO2 and O2 analysis device, and realizes the reaction time and accuracy of CO2 and O2 measurement.

Description

Technical Field

[0001] The present invention relates to the technical field of photoelectric sensors, and more particularly to an optical fiber type CO2 and O2 concentration rapid collection probe. Background Art

[0002] The human body needs oxygen to burn the energy stored in the body and turn it into heat energy, which is needed for organs and muscles to move. Oxygen is inhaled by the lungs, so the size of the lungs and the number of lung movements are very important; the heart is responsible for sending oxygen to various organs and parts through the blood circulation system, so the strength of the heartbeat will affect the blood flow.

[0003] Therefore, cardiopulmonary function includes the blood circulation speed, the strength of the heartbeat, the capacity and frequency of the lungs. To measure cardiopulmonary function, it is best to conduct an exercise test, because the human body has a very large demand for oxygen during exercise, so it is the best way to test the activity of the heart and lungs. Cardiopulmonary function refers to a person's ability to absorb oxygen and convert oxygen into energy. The whole process involves the heart's blood production and pumping function, the lungs' oxygen absorption and gas exchange capacity, the efficiency of the blood circulation system in carrying oxygen to all parts of the body, and the muscle's ability to use this oxygen. The cardiopulmonary exercise test is to judge the reserve function of the heart, lungs, skeletal muscles, etc. and the actual tolerance of the body to exercise by observing the various reactions of the subjects during exercise, such as breathing, blood pressure, heart rate, electrocardiogram, gas metabolism, clinical symptoms and signs. Cardiopulmonary endurance can characterize the ability of the human body to continue physical activity, and reflect the cardiopulmonary function of the human body under a certain exercise intensity. It is one of the important indicators in the health fitness evaluation index system. When conducting a cardiopulmonary endurance test, it is necessary to detect the subject's respiratory gas parameters such as the flow rate of respiratory gas, oxygen concentration and carbon dioxide concentration of respiratory gas.

[0004] However, in the prior art, the oxygen concentration and carbon dioxide concentration of respiratory gas are measured by sampling at the respiratory end using a sampling pump and then analyzing the sample, which results in a high delay in the analysis results and cannot be synchronized with the flow curve. In addition, due to molecular motion, the gas after sampling is mixed, resulting in inaccurate results.

[0005] Therefore, how to provide a fiber-optic CO2 and O2 concentration rapid collection probe that can perform real-time sampling of oxygen and carbon dioxide in respiratory gas to ensure accurate detection results is an urgent problem that technical personnel in this field need to solve. Summary of the invention

[0006] In existing cardiopulmonary exercise testers, the flow rate of respiratory gas is generally measured by a flow sensor, which can detect the flow rate of respiratory gas in real time and output an electrical signal curve. However, when detecting the oxygen concentration and carbon dioxide concentration, when sampling the respiratory gas of the subject, the respiratory gas must pass through an air guide hose to reach the detection device end, and then the oxygen concentration and carbon dioxide concentration are detected. The respiratory gas samples collected by this method have the following defects during detection. First, the air guide hose has a certain length, and it takes a certain amount of time for the respiratory gas to reach the detection device end. Therefore, the detection results of the oxygen concentration and carbon dioxide concentration are inconsistent with the detection results of the respiratory gas flow. Synchronization causes a lag in the analysis of the results; secondly, during the circulation of respiratory gases in the air guide tube, collisions will occur between gas molecules, and at the same time, the diameters of various parts of the air guide tube will also be different, so the order in which the respiratory gases circulate in the air guide tube will change, that is, the gas exhaled later may be mixed with the gas exhaled earlier, causing the sampling to not be carried out in the order of breathing, and it is difficult to collect samples at the same breathing time, resulting in the samples for detecting oxygen and carbon dioxide concentrations and the samples for detecting respiratory gas flow not being samples at the same breathing time, causing inaccurate comprehensive analysis of the subjects' respiratory gas parameters, thereby affecting the judgment results of the subjects' comprehensive indicators.

[0007] The present invention aims to solve one of the above-mentioned technical problems in the prior art at least to a certain extent.

[0008] To this end, one purpose of the present invention is to propose a fiber optic CO2, O2 concentration rapid collection probe to solve the technical problems of the inability to perform real-time sampling of oxygen concentration and carbon dioxide concentration in existing cardiopulmonary exercise tests, high delay and large error rate.

[0009] In order to achieve the above-mentioned object, the present invention adopts the following technical scheme: an optical fiber type CO2 and O2 concentration rapid collection probe, comprising a light emitting part, a light receiving part and an optical fiber body;

[0010] The light emitting unit includes a first light emitting element and a second light emitting element; the first light emitting element emits a laser beam having a wavelength band including a light absorption spectrum of a first measurement target gas; the second light emitting element emits a laser beam having a wavelength band including a light absorption spectrum of a second measurement target gas;

[0011] The optical fiber body is in a hollow cylindrical shape, with a glass light guide column provided inside and a protective sleeve provided outside, and the light receiving part is provided in the middle of the inner side of the glass light guide column;

[0012] The light receiving part comprises an elliptical carrier, an oxygen fluorescence sensitive film and a carbon dioxide fluorescence sensitive film; the oxygen fluorescence sensitive film and the carbon dioxide fluorescence sensitive film are attached to two surfaces of the elliptical carrier.

[0013] By adopting the above technical scheme, the present invention emits laser light through the first light-emitting element and the second light-emitting element, and irradiates the laser light on the respiratory gas. The respiratory gas is scattered and reflected to the oxygen fluorescence sensitive film and the carbon dioxide fluorescence sensitive film on the elliptical carrier of the light receiving part, so that the first light-emitting element and the second light-emitting element irradiate the oxygen fluorescence sensitive film and the carbon dioxide fluorescence sensitive film after scattering and reflection. The elliptical oxygen fluorescence sensitive film and the carbon dioxide fluorescence sensitive film are designed to have a large receiving area for the scattered and reflected light, so that the fluorescence can be received with maximum efficiency. Therefore, the present invention can effectively reduce the energy loss of light transmission, and has the characteristics of high fluorescence excitation efficiency, high light energy utilization, high fluorescence receiving efficiency and high detection efficiency.

[0014] Furthermore, the major axis of the elliptical carrier is the same as the diameter of the glass light guide column.

[0015] Furthermore, the glass light guide column protrudes from the optical fiber body and forms an angle of 10°-45° with the optical fiber body.

[0016] Preferably, the glass light guide column protrudes from the optical fiber body and forms an angle of 30° with the optical fiber body.

[0017] The adoption of the above technical solution can not only ensure the reflection area of ​​the laser emitted by the first light-emitting element and the second light-emitting element, ensure the accuracy of the measurement of oxygen concentration and carbon dioxide concentration, but also ensure the mechanical strength of the overall glass light guide column and the optical fiber body, and reduce collision damage during installation.

[0018] Furthermore, it also includes a signal receiving device disposed in the middle of the elliptical carrier, the signal receiving device converting the optical signal into an electrical signal. Preferably, the signal receiving device is a charge coupled photodetector.

[0019] Furthermore, the wavelength of the laser emitted by the first light emitting element and the second light emitting element is 2-450nm; the strong absorption line is 6359.97cm -1 , namely R16e, with a line intensity of 1.744E23cm / mol and a second weak line of 6362.5cm -1 , that is, R20e, the spectral line intensity is 1.623E23cm / mol.

[0020] Furthermore, the oxygen fluorescence sensitive membrane and the carbon dioxide fluorescence sensitive membrane are both obtained by fixing the fluorescence sensitive substance in a certain inorganic or organic semi-permeable membrane material through sol-gel technology.

[0021] Preferably, the oxygen fluorescence sensitive membrane is selected as follows: a carbon fluoride sol-gel matrix embedded with a fluorescent substance is selected, wherein the molar ratio of the fluorescent substance to the carbon fluoride sol-gel matrix is ​​1 to 30. The fluorescent substance is a metal ruthenium complex, a metal osmium complex, a metal lead complex, a metal platinum complex, a metal palladium complex, or a metal rhenium complex; the carbon fluoride sol-gel matrix is ​​a hydrolysis copolymer of trifluoropropyl trimethoxysilane TFP-TriMOS and other siloxane monomers; the volume ratio of TFP-TriMOS to other siloxane monomers is 0.25 to 4; and other siloxane monomers are tetramethoxysilane TMOS, tetraethoxysilane TEOS, methyl trimethoxysilane MTMOS, methyl triethoxysilane MTEOS, propyl trimethoxysilane PTMOS, or propyl triethoxysilane PTEOS.

[0022] Preferably, the choice of carbon dioxide fluorescence sensitive membrane: a polyvinyl chloride sensitive membrane with Ye Lin fixed on it based on the principle of fluorescence quenching. The principle is to utilize the fluorescence enhancement effect of cyclodextrin on Ye Lin, and the fluorescence can be quenched by carbon dioxide in the solution. The membrane has fast response speed, good reproducibility, and strong anti-interference ability. The range of carbonic acid determination reaches 4.75×10-7~3.90×10-5mol / L.

[0023] By adopting the above technical scheme, the oxygen fluorescence sensitive membrane and the carbon dioxide fluorescence sensitive membrane of the present invention have short time for measuring oxygen concentration and carbon dioxide concentration. The present invention has essentially avoided the sampling time delay and O2 and CO2 measurement delay caused by the traditional O2 and CO2 measurement from the flow meter through the micro pump sampling, and then sent to the relatively slow-reacting O2 and CO2 measurement devices for measurement respectively, thereby reducing the error of continuous dynamic accumulation calculation of oxygen intake and carbon dioxide emissions in each breathing cycle, and improving the accuracy of instrument detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0025] Figure 1 The accompanying drawings are CO2, O2 concentration and flow measurement curves in the prior art provided by the present invention;

[0026] Figure 2 The accompanying drawings are curves of CO2, O2 concentration and flow rate error adjustment in the prior art provided by the present invention;

[0027] Figure 3The accompanying drawing is a schematic diagram of the overall structure of an optical fiber type CO2, O2 concentration rapid collection probe provided by the present invention;

[0028] Figure 4 The accompanying drawing is a schematic diagram of the cross-sectional structure of an optical fiber type CO2 and O2 concentration rapid collection probe provided by the present invention.

[0029] In the figure, 1 is the light-emitting part, 11 is the first light-emitting element, 12 is the second light-emitting element, 2 is the light-receiving part, 21 is the elliptical carrier, 22 is the oxygen fluorescence sensitive film, 23 is the carbon dioxide fluorescence sensitive film, 3 is the optical fiber column, 31 is the glass light guide column, and 32 is the protective cover. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] like Figure 1-2 As shown: In the prior art, the existing cardiopulmonary exercise tester generally uses a flow sensor for the flow of respiratory gas, which can detect the flow of respiratory gas in real time and output an electrical signal curve. However, when detecting the oxygen concentration and carbon dioxide concentration, when sampling the subject's respiratory gas, the respiratory gas must pass through an air guide hose to reach the detection device end, and then the oxygen concentration and carbon dioxide concentration are detected.

[0032] In the figure: 1. There is a time interval of approximately 300 milliseconds between the start of expiratory flow and the start of concentration change volume signal from the anatomically exhaled dead space.

[0033] 2. A sudden change in concentration occurs at the end of exhalation and the flow rate passes zero.

[0034] 3. Flow integration starts when respiratory flow stops exceeding a threshold flow rate. Digitization frequency: 125 Hz. Plot interval: 24 ms.

[0035] The respiratory gas samples collected by this method have the following defects during detection. First, the air guide hose has a certain length, and it takes a certain amount of time for the respiratory gas to reach the detection equipment. Therefore, the detected oxygen concentration and carbon dioxide concentration results are not synchronized with the detection results of the respiratory gas flow, resulting in a lag in the result analysis. Second, during the circulation of the respiratory gas in the air guide hose, collisions will occur between gas molecules, and the diameters of various parts of the air guide hose will also be different. Therefore, the order in which the respiratory gas circulates in the air guide hose will change, that is, the gas exhaled later may be mixed with the gas exhaled earlier, resulting in the sampling not being able to be performed in the order before and after breathing, and it is difficult to collect samples at the same breathing time, resulting in the samples for detecting oxygen and carbon dioxide concentrations and the samples for detecting respiratory gas flow not being samples at the same breathing time, resulting in inaccurate comprehensive analysis of the subject's respiratory gas parameters, thereby affecting the judgment results of the subject's comprehensive indicators.

[0036] like Figure 3-4 As shown: This embodiment discloses a fiber-optic CO2, O2 concentration rapid collection probe, including a light-emitting part 1, a light-receiving part 2 and a fiber main body 3;

[0037] The light emitting unit 1 includes a first light emitting element 11 and a second light emitting element 12; the first light emitting element 11 emits a laser beam having a wavelength band including a light absorption spectrum of a first measurement target gas; the second light emitting element 12 emits a laser beam having a wavelength band including a light absorption spectrum of a second measurement target gas;

[0038] The optical fiber body 3 is a hollow cylinder, with a glass light guide column 31 disposed inside and a protective cover 32 disposed outside, and the light receiving part 2 is disposed in the middle of the inner side of the glass light guide column 31;

[0039] The light receiving part 2 includes an elliptical carrier 21 , an oxygen fluorescence sensitive film 22 and a carbon dioxide fluorescence sensitive film 23 ; the oxygen fluorescence sensitive film 22 and the carbon dioxide fluorescence sensitive film 23 are attached to two surfaces of the elliptical carrier 21 .

[0040] In this embodiment, the first light-emitting element 11 and the second light-emitting element 12 emit laser light, which is irradiated on the respiratory gas. The respiratory gas is scattered and reflected to the oxygen fluorescence sensitive film 22 and the carbon dioxide fluorescence sensitive film 23 on the elliptical carrier 21 of the light receiving part 2, so that the first light-emitting element 11 and the second light-emitting element 12 are irradiated on the oxygen fluorescence sensitive film 22 and the carbon dioxide fluorescence sensitive film 23 after scattering and reflection. The elliptical oxygen fluorescence sensitive film 22 and the carbon dioxide fluorescence sensitive film 23 are designed to have a large receiving area for the scattered and reflected light, so that the fluorescence can be received with maximum efficiency. Therefore, the present invention can effectively reduce the energy loss of light transmission, and has the characteristics of high fluorescence excitation efficiency, high light energy utilization, high fluorescence receiving efficiency and high detection efficiency.

[0041] In this embodiment, the major axis of the elliptical carrier 21 is the same as the diameter of the glass light guide column 31 .

[0042] In this embodiment, the glass light guide column 31 protrudes from the optical fiber body 3 and forms an angle of 30° with the optical fiber body 3 .

[0043] In other embodiments, the glass light guide column 31 protrudes from the optical fiber body 3 and forms an angle of 10°-45° with the optical fiber body 3 .

[0044] The above technical solution can ensure the reflection area of ​​the laser emitted by the first light-emitting element 11 and the second light-emitting element 12, ensure the accuracy of the measurement of oxygen concentration and carbon dioxide concentration, and ensure the mechanical strength of the overall glass light guide column 31 and the optical fiber body 3, and reduce collision damage during installation.

[0045] In this embodiment, a signal receiving device is also included in the middle of the elliptical carrier 21, and the signal receiving device converts the optical signal into an electrical signal. Preferably, the signal receiving device is a charge coupled photodetector.

[0046] In some other embodiments, the wavelength of the laser emitted by the first light emitting element 11 and the second light emitting element 12 is 2-450nm; the strong absorption line is 6359.97cm -1 , namely R16e, with a line intensity of 1.744E23cm / mol and a second weak line of 6362.5cm -1 , that is, R20e, the spectral line intensity is 1.623E23cm / mol.

[0047] The laser in this embodiment has a peak wavelength of 450nm, which covers the absorption spectrum of the luminescent body. In this embodiment, a strong absorption line 6359.97cm-1, namely R16e, with a line intensity of 1.744E23cm / mol and a second weak line 6362.5cm-1, namely R20e, with a line intensity of 1.623E23cm / mol are used.

[0048] In this embodiment, both the oxygen fluorescence sensitive membrane 22 and the carbon dioxide fluorescence sensitive membrane 23 are obtained by fixing the fluorescence sensitive substance in a certain inorganic or organic semi-permeable membrane material through sol-gel technology.

[0049] Specifically, the oxygen fluorescence sensitive film 22 is selected as follows: a carbon fluoride sol-gel matrix embedded with fluorescent substances is selected, wherein the molar ratio of the fluorescent substances to the carbon fluoride sol-gel matrix is ​​1 to 30. The fluorescent substances are metal ruthenium complexes, metal osmium complexes, metal lead complexes, metal platinum complexes, metal palladium complexes, and metal rhenium complexes; the carbon fluoride sol-gel matrix is ​​a hydrolysis copolymer of trifluoropropyl trimethoxysilane TFP-TriMOS and other siloxane monomers; the volume ratio of TFP-TriMOS to other siloxane monomers is 0.25 to 4; and other siloxane monomers are tetramethoxysilane TMOS, tetraethoxysilane TEOS, methyl trimethoxysilane MTMOS, methyl triethoxysilane MTEOS, propyl trimethoxysilane PTMOS, or propyl triethoxysilane PTEOS.

[0050] Specifically, the selection of carbon dioxide fluorescence sensitive membrane 23: a polyvinyl chloride sensitive membrane with Ye Lin fixed thereon based on the principle of fluorescence quenching, the principle of which is to utilize the fluorescence enhancement effect of cyclodextrin on Ye Lin, and the fluorescence can be quenched by carbon dioxide in the solution. The membrane has fast response speed, good reproducibility, and strong anti-interference ability, and the range of carbonic acid determination reaches 4.75×10-7~3.90×10-5mol / L.

[0051] The oxygen fluorescence sensitive membrane 22 and the carbon dioxide fluorescence sensitive membrane 23 of this embodiment have a short time for measuring oxygen concentration and carbon dioxide concentration. The present invention has essentially avoided the sampling time delay and O2 and CO2 measurement delay caused by the traditional O2 and CO2 measurement from the flow meter through a micro pump sampling, and then sent to the relatively slow-reacting O2 and CO2 measurement devices for separate measurement, thereby reducing the error of continuous dynamic accumulation calculation of oxygen intake and carbon dioxide emissions in each breathing cycle, and improving the accuracy of instrument detection.

[0052] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0054] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A fiber-optic CO2 and O2 concentration rapid collection probe, characterized in that: It comprises a light emitting part (1), a light receiving part (2) and an optical fiber body (3); The light emitting unit (1) comprises a first light emitting element (11) and a second light emitting element (12); the first light emitting element (11) emits a laser beam having a wavelength band including a light absorption spectrum of a first measurement target gas; the second light emitting element (12) emits a laser beam having a wavelength band including a light absorption spectrum of a second measurement target gas; the wavelength of the laser beams emitted by the first light emitting element (11) and the second light emitting element (12) is 2-450 nm; the strong absorption line is 6359.97 cm -1 , namely R16e, with a line intensity of 1.744E23cm / mol and a second weak line of 6362.5cm -1 , i.e. R20e, the line intensity is 1.623E23cm / mol; The optical fiber body (3) is in the shape of a hollow cylinder, a glass light guide column (31) is provided on the inner side, and a protective sleeve (32) is provided on the outer side, and the light receiving part (2) is provided in the middle part of the inner side of the glass light guide column (31); The light receiving part (2) comprises an elliptical carrier (21), an oxygen fluorescence sensitive film (22) and a carbon dioxide fluorescence sensitive film (23); the oxygen fluorescence sensitive film (22) and the carbon dioxide fluorescence sensitive film (23) are attached to two surfaces of the elliptical carrier (21); The major axis of the elliptical carrier (21) is the same as the diameter of the glass light guide column (31); The glass light guide column (31) protrudes from the optical fiber body (3) and forms an angle of 10° to 45° with the optical fiber body (3); The oxygen fluorescence sensitive film (22) is composed of a carbon fluoride sol-gel matrix embedded with a fluorescent substance; The carbon dioxide fluorescence sensitive membrane (23) is a polyvinyl chloride sensitive membrane fixed with chlorinated polyol based on the principle of fluorescence quenching.

2. The optical fiber type CO2 and O2 concentration rapid acquisition probe according to claim 1, characterized in that: It also includes a signal receiving device arranged in the middle of the elliptical carrier (21), and the signal receiving device converts the optical signal into an electrical signal.

3. The optical fiber type CO2, O2 concentration rapid acquisition probe according to any one of claims 1-2, characterized in that: The fluorescent substance is a metal ruthenium complex, a metal osmium complex, a metal lead complex, a metal platinum complex, a metal palladium complex, or a metal rhenium complex; and the carbon fluoride sol-gel matrix is ​​a hydrolysis copolymer of trifluoropropyltrimethoxysilane TFP-TriMOS and other siloxane monomers.

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