CN219417371U - Enrichment device for improving ammonia detection sensitivity of nasal cavity exhaling tail end - Google Patents

Enrichment device for improving ammonia detection sensitivity of nasal cavity exhaling tail end Download PDF

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CN219417371U
CN219417371U CN202223031135.3U CN202223031135U CN219417371U CN 219417371 U CN219417371 U CN 219417371U CN 202223031135 U CN202223031135 U CN 202223031135U CN 219417371 U CN219417371 U CN 219417371U
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enrichment
nasal cavity
way electromagnetic
electromagnetic valve
exhaled
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蒋丹丹
王露
王新
李杭
李海洋
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Dalian Institute of Chemical Physics of CAS
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Dalian Institute of Chemical Physics of CAS
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Abstract

The utility model relates to an enrichment device for improving ammonia detection sensitivity of a nasal cavity exhaling tail end, and belongs to the technical field of chemical analysis and detection. The enrichment device comprises: nasal cavity expired air sampling port and expired air CO 2 The sensor, the first three-way electromagnetic valve, the enrichment chamber, the second sampling pump, the second three-way electromagnetic valve, the third three-way electromagnetic valve, the separationSub-migration spectrum and the like, the enrichment chamber is a closed chamber, the enrichment chamber is connected with different gas paths through three-way electromagnetic valves, the nasal cavity exhaled end gas is collected through an on-line enrichment method, a single photon ion migration spectrum on-line detection technology of direct photoionization is adopted, meanwhile, the influence of humidity in exhaled air is reduced through purging pre-separation sample introduction, and the interference of other components is eliminated, so that the sensitivity of ammonia detection of the nasal cavity exhaled end gas is improved, the sensitivity and specific signal response to low-concentration ppbv ammonia in human exhaled air are very high, and the accurate quantification of nasal cavity exhaled ammonia in the concentration range of 100-200ppb is realized.

Description

Enrichment device for improving ammonia detection sensitivity of nasal cavity exhaling tail end
Technical Field
The utility model belongs to the field of analytical chemistry instrument detection, and particularly relates to an enrichment device for improving ammonia detection sensitivity of nasal cavity exhalate tail end gas.
Background
Ammonia is an important component of human metabolism, participates in a plurality of physiological processes of human body, is closely related to diseases such as renal failure, liver cirrhosis or hepatitis, hepatic encephalopathy, helicobacter pylori infection, halitosis and the like, and is also a potential biomarker for exercise physiology and drug metabolism research. Meanwhile, ammonia has neurotoxicity, and rapid bedside monitoring is important for the identification and early warning of critical diseases.
Thousands of components exist in the exhaled air, the exhaled air ammonia is closely related to the functional metabolism of various organs of a human body, the nasal exhaled air ammonia can better reflect the real ammonia concentration of alveolar exchange, but the concentration range of the nasal exhaled air ammonia is 200ppb, and the concentration is relatively lower than the concentration of the oral exhaled air ammonia of 200-2000 ppb. Alveolar ammonia partial pressure and arterial ammonia partial pressure are nearly equal, so that changes in the end-of-expiration ammonia concentration level may suggest corresponding pathophysiological changes, but how to obtain end-of-expiration ammonia concentration is an urgent issue to be addressed.
The existing detection method of the nasal exhaled breath ammonia comprises gas chromatography, photometry, a sensor, other methods and the like, wherein the chromatographic method and the chromatographic-mass spectrometry technology are most widely applied to the detection of the exhaled breath ammonia, but have the defects of higher cost, large volume, special technician operation and the like, the photometry has simple operation steps, but has poor stability and reproducibility, and the sensor method has the advantages of microminiaturization, short response time and the like, but has inaccurate quantification and the like.
Aiming at the problems existing in the nasal cavity ammonia detection, the utility model designs an enrichment device for improving the sensitivity of nasal cavity exhaled air ammonia, adopts a photoionization ion mobility spectrometry to detect the nasal cavity tail end exhaled air ammonia, and uses the enrichment device to sample and enrich the exhaled air tail end ammonia, thereby further improving the sensitivity of the nasal cavity tail end ammonia, and being applicable to the quantitative detection of the ammonia content in the nasal cavity exhaled air of a human body. The method has the characteristics of no wound, simplicity, rapidness, high efficiency, low cost and the like, and provides an effective detection method for monitoring functions of organs such as liver and kidney and the like.
Disclosure of Invention
The technical problems to be solved by the utility model are as follows: the sensitivity of the nasal cavity exhaled breath ammonia detection is improved, the influence of the nasal cavity humidity on the exhaled breath ammonia detection sensitivity in a single respiratory cycle is reduced, the sampling enrichment of exhaled breath at the tail end is realized through the enrichment sampling device, the sensitivity of the nasal cavity exhaled breath ammonia detection is improved, the influence of humidity in exhaled breath can be eliminated in the sample injection process, the influence of high humidity (100% RH) in exhaled breath and other components in exhaled breath on the detection of trace low-concentration ppbv ammonia in exhaled breath is solved, and the method can be used for the correlation research of exhaled breath ammonia concentration and organ function monitoring clinical diagnosis models.
The device for improving the ammonia gas detection sensitivity of the tail end of nasal cavity exhalation comprises a nasal cavity exhalation gas sampling port, and exhalation gas CO 2 The device comprises a sensor, a first three-way electromagnetic valve, an enrichment chamber, a second sampling pump, a second three-way electromagnetic valve, a third three-way electromagnetic valve and an ion mobility spectrometry;
the enrichment chamber is a closed chamber, a left through hole is formed in the left side wall surface of the enrichment chamber, the left through hole is connected with a first outlet of a first three-way electromagnetic valve through a pipeline, and a second outlet of the first electromagnetic valve is connected with an exhaust gas channel of exhaled gas; a right through hole is formed in the right side wall surface of the enrichment cavity, and the right through hole is sequentially connected with a second sampling pump and a second mass flowmeter through a pipeline and then is vented (connected with the atmosphere);
inlet of first three-way electromagnetic valveThe nasal cavity exhaled air sampling tube is connected with the outlet end of the nasal cavity exhaled air sampling tube, and the inlet end of the nasal cavity exhaled air sampling tube is a nasal cavity exhaled air sampling port; a bypass is arranged on the tube wall of the nasal cavity exhaled air sampling tube, and the bypass is sequentially provided with exhaled air CO 2 The sensor, the first sampling pump and the first mass flowmeter are then vented;
an upper through hole is formed in the upper wall surface of the enrichment cavity and is connected with a second outlet of a second three-way electromagnetic valve through a pipeline, and an inlet of the second three-way electromagnetic valve is connected with a clean compressed air inlet pipe;
a lower through hole is arranged on the lower wall surface of the enrichment chamber and is connected with a second inlet of the third three-way electromagnetic valve through a pipeline; the outlet of the third three-way electromagnetic valve is connected with the air inlet of the ion mobility spectrometry through a pipeline;
one end of a clean air pipeline is connected with a first outlet of the second three-way electromagnetic valve, and the other end of the clean air pipeline is connected with a first inlet of the third three-way electromagnetic valve.
The ion mobility spectrometry is a photoionization ion mobility spectrometry, and the photoionization ion mobility spectrometry is adopted to detect the ammonia of the enriched nasal cavity exhaled end gas in a positive ion mode, so that the sensitivity of nasal cavity exhaled end gas ammonia detection is improved.
The quantitative ring is arranged in the enrichment cavity or enrichment materials are filled in the enrichment cavity, the volume range of the enrichment cavity is 10-50mL, different enrichment materials are selected according to the components of the exhaled end gas to be detected, and the like, the temperature range of the enrichment cavity is 10-20 ℃ in the enrichment sampling process, the adsorption content is increased, the temperature range is 80-150 ℃ in the purging sample injection process, the target components are promoted to be heated and volatilized, and different enrichment and analysis temperatures are set according to different exhaled gas detection target components.
In the detection process, the temperature of the ion migration tube in the ion migration spectrum is controlled to be 40-150 ℃, and the exhaled breath ammonia is detected in the temperature range, so that the method has good signal response and specificity.
The enrichment sampling method by adopting the device comprises the following three processes: the method comprises the steps of respectively carrying out a nasal cavity exhalation process, an enrichment sampling process after judging the end gas exhaled by the nasal cavity and a purging pre-separation sampling process;
in the sampling and sample feeding process, according to the expired CO acquired in real time 2 Judging the tail gas of the nasal cavity by using a curve to perform sampling enrichment detection, wherein the CO of a normal person is detected 2 The respiration profile is about 5 seconds, including a: baseline: the inhalation baseline, should be at zero position, the beginning of exhalation is dead space gas in airway, and is substantially free of CO 2 The method comprises the steps of carrying out a first treatment on the surface of the The expiration ascending branch is steeper and is the mixed gas of alveolar gas and dead space gas; corner changes refer to alveolar gas; d: the curve portion represents the average alveolar gas concentration; e: expired end gas CO 2 Values (mmHg); f: the corner represents a portion of the switching to the inhalation cycle; g: the inspiratory portion curve shows a rapid decrease in CO 2 Concentration.
Firstly, in the nasal cavity expiration process, nasal cavity expiration enters a nasal cavity expiration sampling tube through a nasal cavity expiration sampling port, and expiration CO is arranged through a nasal cavity expiration sampling tube bypass 2 The sensor starts a first sampling pump to sample the exhaled breath in real time, the flow rate of the sampling is controlled to be 20-100mL/min by a first mass flowmeter, and the exhaled breath CO is monitored in real time 2 The curve is that the second outlet of the first three-way electromagnetic valve is switched at the moment and is connected with an exhaust gas channel of the exhaled gas, the exhaled gas is in an exhaust state, and one path of clean compressed air passes through the first outlet of the second three-way electromagnetic valve and a clean air pipeline to the third three-way electromagnetic valve and finally enters an ion mobility spectrometry for detection, so that a blank background ion mobility spectrometry of the clean compressed air is obtained;
then, during the sampling and enrichment process of the nasal cavity exhaled end gas, when the system is based on the exhaled CO 2 Curve, judging the end gas CO of exhale 2 After peak E, i.e. exhaled breath CO 2 When the concentration value reaches the highest value and drops rapidly, the gas is switched to an enrichment sampling gas circuit, at the moment, nasal cavity exhaled gas enters a nasal cavity exhaled gas sampling pipe through a nasal cavity exhaled gas sampling port, a first three-way electromagnetic valve is switched to a first outlet gas circuit, a second sampling pump is started simultaneously, the exhaled terminal gas is enriched and sampled into an enrichment chamber, the volume range of the enrichment chamber is 10-50mL, the sampling flow rate is controlled to be 50-150mL/min through a second mass flowmeter, and after the exhaled terminal gas is endedI.e. exhaled breath CO 2 Concentration drop to exhaled CO 2 When the intensity of the gas at the highest concentration is 1/3, the second sampling pump stops sampling, and the gas enrichment sampling at the end of the exhalation is finished, and the exhalation is stopped;
and finally, purging the preseparation sample injection process, switching the first three-way electromagnetic valve to a second outlet to be connected with an air exhaust path of the exhaled air, wherein the exhaled air is in an air exhaust state, switching the second three-way electromagnetic valve to the second outlet to purge and sample the exhaled air, purging the enrichment chamber by clean compressed air through a clean compressed air inlet pipe, switching the third three-way electromagnetic valve to a second air inlet, and purging the enriched air into an ion mobility spectrometry for detection, wherein the flow rate of the clean compressed air is 50-200mL/min.
The enrichment device can be used for detecting ammonia gas at the exhalation end of the nasal cavity, and detecting other components of the exhalation end gas in the nasal cavity, such as acetone, hydrogen cyanide HCN and hydrogen sulfide H 2 S, etc. only need to adopt different ion mobility spectrometry working modes, such as detecting exhaled breath ammonia and acetone in positive ion mode, and detecting exhaled breath HCN and H in negative ion mode 2 S, etc.
Drawings
FIG. 1 is a schematic diagram of a nasal exhalation process, wherein 1 is a nasal exhalation sampling port, 2 is a nasal exhalation sampling tube, and 3 is exhalation CO 2 The sensor is characterized by comprising a first sampling pump 4, a first mass flowmeter 5, a first three-way electromagnetic valve 6, an expired air exhausting channel 7, an enrichment chamber 8, a second sampling pump 9, a second mass flowmeter 10, a second three-way electromagnetic valve 11, a clean compressed air inlet pipe 12, a clean air pipeline 13, a third three-way electromagnetic valve 14 and an ion mobility spectrometry 15.
Fig. 2 is a blank background ion mobility spectrum of clean compressed air.
Figure 3 is a schematic diagram of the process of sample enrichment of exhaled end gases from the nasal cavity.
FIG. 4 real-time monitoring of exhaled CO 2 A curve.
Fig. 5 is a schematic diagram of a process for detecting purge preseparation sample introduction of exhaled end gas of nasal cavity.
FIG. 6 is a two-dimensional ion mobility spectrum of the enriched detected exhaled breath end ammonia.
Detailed Description
Example 1
An enrichment device for improving ammonia detection sensitivity of nasal cavity exhaled air is shown in figure 1, and is characterized in that in the nasal cavity exhalation process, nasal cavity exhaled air enters a nasal cavity exhaled air sampling tube 2 through a nasal cavity exhaled air sampling port 1, and exhaled air CO is arranged by-pass of the nasal cavity exhaled air sampling tube 2 2 The sensor 3 starts the first sampling pump 4 to sample the exhaled breath in real time, the first mass flowmeter 5 controls the sampled flow rate to be 50mL/min, and the exhaled breath CO is monitored in real time 2 Judging the expired air by the curve, switching the second outlet of the first three-way electromagnetic valve 6 to be connected with the expired air exhausting circuit 7, wherein the expired air is in an exhausted state, and one path of clean compressed air passes through the first outlet of the second three-way electromagnetic valve 11, the clean air pipeline 13 and the third three-way electromagnetic valve 14 and finally enters the ion mobility spectrometry to be detected, so as to obtain a blank background ion mobility spectrometry of the clean compressed air, wherein the migration time of acetone reagent ions is 5.00ms and the signal intensity is 2480mV as shown in fig. 2.
Example 2
As shown in fig. 3, the expired CO is acquired from real-time 2 The curve judges the nasal cavity end gas to sample and enrich and detect, as shown in figure 4, wherein, the normal person CO 2 Respiration profile for about 5 seconds, including a as inhalation baseline: the inhalation baseline, should be at zero position, the beginning of exhalation is dead space gas in airway, and is substantially free of CO 2 The method comprises the steps of carrying out a first treatment on the surface of the B is an ascending branch of expiration, is steeper and is mixed gas of alveolar gas and dead space gas; corner C changes to alveolar gas; d is the average alveolar gas concentration; e is exhaled end gas CO 2 Values (mmHg); corner F represents a portion of the switching to the inhalation cycle; the inspiratory portion curve at G shows a rapid decrease in CO 2 Concentration.
During the sampling and enrichment of the nasal cavity exhaled end gas, when the system is based on the exhaled CO 2 Curve, after judging the end gas E of exhaling, namely the CO of exhaling 2 When the concentration value reaches the highest value and rapidly drops, the concentration value is switched to an enrichment sampling gas path, and the nasal cavity exhales gas at the momentThe gas enters the nasal cavity exhaled gas sampling tube 2 through the nasal cavity exhaled gas sampling port 1, the first three-way electromagnetic valve 6 is switched to a first outlet gas circuit, and the second sampling pump 9 is started simultaneously, the exhaled terminal gas is enriched and sampled into the enrichment chamber 8, the enrichment filler filled in the enrichment chamber 8 is a mixed material of activated carbon and activated silica gel, the volume range of the enrichment chamber is 30mL, the set temperature is 15 ℃, the flow rate of sampling is controlled to be 100mL/min through the second mass flowmeter 10, and the exhaled gas CO is obtained after the exhaled terminal gas is finished 2 Concentration drop to exhaled CO 2 At 1/3 of the intensity of the highest concentration, the second sampling pump 9 stops sampling, and the end gas enrichment sampling of the exhale is completed, and the exhale is stopped.
Example 3
In the process of purging pre-separation sample injection, as shown in fig. 5, the first three-way electromagnetic valve 6 is switched to the second outlet to be connected with the exhaust gas channel 7 of the exhaled gas, the exhaled gas is in an exhausted state, the second three-way electromagnetic valve 11 is switched to the second outlet to purge sample injection, clean compressed air is purged through the clean compressed air inlet pipe 12 to the enrichment chamber 8, meanwhile, the third three-way electromagnetic valve 14 is switched to the second air inlet to purge the enriched gas into the ion mobility spectrometry for detection, the temperature set in the enrichment chamber is 100 ℃, the flow rate of the clean compressed air is 100mL/min, the temperature of an ion mobility tube in the ion mobility spectrometry is 80 ℃, the ion mobility spectrometry of ammonia at the tail end of the exhaled gas is obtained, as shown in fig. 6, the migration time of the exhaled gas ammonia is 4.08ms, and the signal strength for detecting the exhaled gas ammonia is increased to 2150mV.

Claims (4)

1. Enrichment device for improving ammonia detection sensitivity of nasal cavity exhale tail end, and is characterized in that:
the device comprises: nasal cavity expired air sampling port (1), expired air CO 2 The device comprises a sensor (3), a first three-way electromagnetic valve (6), an enrichment chamber (8), a second sampling pump (9), a second three-way electromagnetic valve (11), a third three-way electromagnetic valve (14) and an ion mobility spectrometry (15);
the enrichment chamber (8) is a closed chamber, a left through hole is formed in the left side wall surface of the enrichment chamber, the left through hole is connected with a first outlet of the first three-way electromagnetic valve (6) through a pipeline, and a second outlet of the first three-way electromagnetic valve (6) is connected with an exhaust gas channel (7) for exhausting the exhaled gas; a right through hole is formed in the right side wall surface of the enrichment cavity (8), and the right through hole is sequentially connected with a second sampling pump (9) and a second mass flowmeter (10) through a pipeline and then is discharged to be connected with the atmosphere;
the inlet of the first three-way electromagnetic valve (6) is connected with the outlet end of the nasal cavity exhaled air sampling tube (2), and the inlet end of the nasal cavity exhaled air sampling tube (2) is a nasal cavity exhaled air sampling port (1); a bypass is arranged on the tube wall of the nasal cavity exhaled air sampling tube (2), and the bypass is sequentially provided with exhaled air CO 2 The sensor (3), the first sampling pump (4) and the first mass flowmeter (5) are then emptied;
an upper through hole is arranged on the upper wall surface of the enrichment chamber (8), the upper through hole is connected with a second outlet of a second three-way electromagnetic valve (11) through a pipeline, and an inlet of the second three-way electromagnetic valve (11) is connected with a clean compressed air inlet pipe (12);
a lower through hole is arranged on the lower wall surface of the enrichment chamber (8), and the lower through hole is connected with a second inlet of the third three-way electromagnetic valve (14) through a pipeline; the outlet of the third three-way electromagnetic valve (14) is connected with the air inlet of the ion mobility spectrometry (15) through a pipeline;
one end of a clean air pipeline (13) is connected with the first outlet of the second three-way electromagnetic valve (11), and the other end is connected with the first inlet of the third three-way electromagnetic valve (14).
2. The enrichment device according to claim 1, wherein: the enrichment chamber is internally provided with a quantitative ring or filled with enrichment materials, the volume range of the enrichment chamber is 10-50mL, the temperature range of the enrichment chamber is 10-20 ℃ in the enrichment sampling process, and the temperature range of the enrichment chamber is 80-150 ℃ in the purging sampling process.
3. The enrichment device according to claim 1, wherein: the ion mobility spectrometry (15) is a photoionization ion mobility spectrometry, and the photoionization ion mobility spectrometry is adopted to detect the ammonia of the enriched nasal cavity exhalant tail gas in a positive ion mode.
4. An enrichment device according to claim 1 or 3, wherein: in the detection process, the temperature of an ion migration tube in the ion mobility spectrometry is controlled to be 40-150 ℃.
CN202223031135.3U 2022-11-15 2022-11-15 Enrichment device for improving ammonia detection sensitivity of nasal cavity exhaling tail end Active CN219417371U (en)

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