JPS60250227A - Test gas sampling apparatus - Google Patents

Abstract

PURPOSE:To facilitate sampling of a test specimen, by installing guide opening of exhaust gas sample, test gas storage with an opening to discharge the exhaust gas sample to a measuring apparatus and pressurized gas chamber provided with a pressurized gas guiding opening of sample. CONSTITUTION:Clean air is filled in an inner bag 1 through a gas passage opening 5 with a dismounted cap 11 and the bag is transported to a subject with the cap 11 fitted again. Further, the subject removes a cap 10 and hold a mouth piece in his mouth and inhales and discharges five times and up the air in the bag 1, then a concentration of gas composition in his lung approaches that of 5l of the air in the bag 1. Further, after the breathing, the cap 10 is fitted and the bag is transported to an atmospheric ionized mass analyzer and connected with a connector 8 and the pressurized gas is introduced into the outer bag 2 through a pressurized gas passage opening 7 discharging the gas inside the bag 1 to an analyzing apparatus. Further, after analysis, nitrogen is introduced from one of the passages 3 and 5 continually to clean up the inside of the bag 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an improvement in a sample gas sampling device such as an atmospheric pressure ionization mass spectrometer, and in particular, in this type of device, human exhaled breath can be easily sampled and the sample gas can be easily sampled. The present invention relates to a sample gas sampling device suitable for measuring concentration without changing it.

[Background of the invention]

Volatile substances contained in blood in the human body are related to various functions of the human body, and measuring them is important in elucidating human body functions and furthermore in diagnosing diseases. It is extremely effective to use exhaled breath as a sample for this volatile substance instead of blood because it can solve the problems that arise when blood is used as a sample. In other words, in blood analysis, it is a burden on the subject to collect the blood, it is impossible to perform continuous iu and lI determinations for the same sample, and in vitro reactions occur between the time the blood is collected and the time it is introduced into the measuring device. ,
There are two major problems in that measurements similar to those in vivo cannot be made. These two problems can be solved if exhaled breath is used as a sample. However, volatile organic substances contained in the blood due to metabolism are extremely small, and since they are excreted in the lungs into exhaled air, the amount becomes even smaller (concentration in exhaled air: ppb-ppt). Detecting this trace amount of substances without sample pretreatment is only possible with a high-sensitivity detector such as an atmospheric pressure ionization mass spectrometer.
The ion source of an atmospheric pressure ionization mass spectrometer requires that the pressure be maintained at about 1 atmosphere.

To this end, the conventional apparatus for introducing a breath sample into an atmospheric pressure ion source is as follows.

■ The sample introduction tube connected to the mouthpiece is directly connected to the ion source, allowing the subject to directly introduce exhaled air into the ion source.The introduction tube has a double tube in the middle and the inner tube is pressed against the nozzle. , the sample coming out of the nozzle is sent to the ion source together with the carrier gas introduced from the bypass.

■ Collect exhaled breath into a plastic bag equipped with two ports: an exhaled air or carrier gas inlet and an exhaled air outlet, place it in the middle of the sample introduction tube, and introduce the carrier gas through the carrier gas inlet of the bag. The sample is delivered to the measuring device using carrier gas pressure.

■ Exhaled air is collected in a plastic bag equipped with an exhaled air inlet, and the sample is passed through an adsorbent to concentrate organic matter, regenerated by heating, and then introduced into the measuring device. However, this conventional device is coupled to a gas chromatograph (GC) rather than an atmospheric pressure ionization mass spectrometer.

The (2) method required the test subject to be present at the location where the equipment was installed, and had the drawback of having to move the sick person from a remote location, making it impossible to recover if the situation was dangerous.

Method (2) is convenient for sample collection, but since the carrier gas is not introduced into the bag during measurement, the sample gas and carrier gas mix, resulting in a decrease in the sample concentration during the measurement, resulting in a very short measurement time. This has the disadvantage that it is not possible to perform long-term measurements, which is not possible when measuring a small amount of sample. That is, since the amount of detected current is weak for trace components, it is necessary to increase the amplification rate of the detection section and improve the S/N ratio. Since the response of the detection unit in this state becomes slow, long-term measurement is required.

Method (2) also allows for easy sample collection and no change in sample concentration during measurement, but requires extremely complicated pretreatment of sample concentration and regeneration, and the measurement efficiency is low, so the number of samples that can be processed in a day is small. However, there was a drawback that it was not possible to process large quantities of samples, which is important for diagnosis and the like.

[Purpose of the invention]

An object of the present invention is to facilitate sample collection when performing breath analysis using an atmospheric pressure ionization mass spectrometer;
Another object of the present invention is to provide an exhaled breath sample collection device that allows the sample to be transported so that the subject does not have to move to the installation location of the atmospheric pressure ionization mass spectrometer, and that does not cause a change in sample concentration during measurement.

[Summary of the invention]

In order to achieve the above object, the present invention includes a bag made of a flexible plastic film for collecting and storing a breath sample, and a bag adjacent to the bag for storing the sample, and a bag for storing the sample at the time of measurement. The sample storage bag is pressurized from the outside in order to lead the sample to the ion source. A bag made of plastic film that allows the gas to flow in, the sample gas, cleaning gas, pressurized gas inlet and outlet, and the sample. It is characterized in that a sample gas sampling device is constituted by a sampling chamber mouthpiece.

With the characteristic configuration of the present invention, there is no need for the subject to go to the trouble of traveling to the measurement device installation location to collect exhaled breath sample gas, and there is no need to apply pressure to lead the sample gas to the atmospheric pressure ion source during measurement. Since there is no mixing between the pressure gas and the sample gas, there is no change in the sample concentration, making it possible to perform long-term measurements for trace sample measurements. The measurable time was 10 to 20 times longer than that of conventional devices.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows a sample gas sampling device according to the present invention. .

In the figure, gas ports 3 and 5 are attached to a plastic inner bag 1 for storing sample gas.

The gas inlets and outlets 3 and 5 are threaded and sealed with the inner bag 1 using a nut 4 and a gasket 6. The plastic outer bag 2 for pressurized gas inflow is the same as the inner bag (at the end there is a gas inlet/outlet 3).
, 5, the nut 4 and the gasket 6 maintain airtightness. Furthermore, a pressurized gas introduction lower is attached to the outer bag 2 and is sealed with a nut 4 and a gasket 6. The gas inlet/outlet 3 is connected to a glass mouthpiece 9 by a coupler 8, and a cap 10 is attached to the mouthpiece 9 to seal the stored sample gas. The gas inlet/outlet 5 is also provided with a cap 11 in the same manner.

Clean air (80% nitrogen, 20% oxygen) with cap 11
The inner bag 1 is filled with gas through the gas inlet/outlet 5, the cap 11f is attached again, and in this state it is transported to a place where the subject is present. The subject removes the cap 10, holds the mouthpiece 9 in his mouth, and breathes in the clean air inside the inner bag 1. When the inner bag volume is 5 tons, if the user takes five or more breaths while holding the mouthpiece 9 in his/her mouth, the gas component concentration in the lungs and the gas component concentration within the inner bag approaches equilibrium. If the number of breaths is 5 or more, the concentration of gas components in the inner bag will change depending on the number of breaths, and if the number of breaths is 15 or more, the oxygen in the inner bag will be consumed, making breathing difficult. The inner diameter of the mouthpiece 9 and gas inlet/outlet 3 is required to be 7 tran or more for a normal adult. After breathing, attach the cap 10 and set up the atmospheric pressure ionization mass spectrometer f
Transported to an illegal location.

FIG. 2 shows the basic configuration when the sample gas sampling device according to the present invention is combined with an atmospheric pressure ionization mass spectrometer. The gas inlet/outlet 3 is connected to the sample introduction tube 18 by the coupler 8 after the cap 10 and mouthpiece 9 are removed. The valve 13 is opened, the valve 12 is closed, and the sample gas in the inner bag 1 is forced out by the pressurized gas and introduced into the atmospheric pressure ion source 15. Either the gas inlet/outlet 3 or 5 may be connected to the sample introduction tube 18 .

The pressurized gas is passed from the cylinder through the pressurized gas introduction lower to the outer bag 2.
be introduced within. For safety reasons, nitrogen is appropriate as the type of pressurized gas. The flow rate of the sample gas introduced into the atmospheric pressure ion source 15 from inside the inner bag 1 is measured by a flow meter 17, and the pressurized gas flow rate is adjusted so that the sample gas flow rate is constant at a desired value. After the measurement is completed, the introduction of pressurized gas is stopped, the coupler 8 and the sample introduction tube 18 are separated, the valve 12 is opened, and pure nitrogen gas is introduced from the cylinder to the sample introduction tube 18 and the atmospheric pressure ion meter 15. Cleaning is carried out. During cleaning, the sample introduction tube 18 and the atmospheric pressure ion source are heated to 150 to 300C. The inner bag 1 of the sample collection device from which the sample was removed is cleaned with clean nitrogen gas. That is, gas inlet/outlet 3
, 5, with the cap removed, clean nitrogen gas from the cylinder is introduced from either the gas inlet/outlet port 3 or 5, and the nitrogen continues to flow to purify the inside of the inner bag 1 (ff1).

This embodiment provides the following effects. Since the conventional apparatus is an online method, there is no need to move the subject from a remote location since the subject is a sick person or the like. In addition, with conventional equipment, during measurement, the sample gas mixes with the pressurized gas used to deliver the sample gas to the atmospheric pressure ion source, causing changes in the concentration of the sample gas components, making it difficult to perform long-term measurements for trace component measurements. However, in this example, gas mixing did not occur (9) until the sample gas was drawn out. A! It is possible to measure time without changing the power ratio. Furthermore, since the sample gas storage bag is a flexible plastic bag, it is possible to take multiple breaths with the air in the sample gas storage bag while keeping the mouthpiece in the mouth, so the production of sample components can be controlled by the number of breaths. There will be less variation. The respiratory capacity for one breath varies greatly among individuals, and the variation is large, but the variation decreases by taking multiple breaths.

FIG. 3 also shows an embodiment according to the present invention. The difference from the embodiment shown in FIG. 1 is that a bag 19 for storing sample gas and a bag 20 for pressurized gas inflow are separated by a single flexible plastic film 21. When the sample gas is introduced into the bag 19 for storing sample gas, the plastic film 21 becomes convex toward the bag 20 for pressurized gas inflow, and as the pressurized gas is introduced into the bag 20 for pressurized gas inflow, The plastic film 21 is convex toward the sample gas storage bag 19 side. In this example, the sample gas sampling method, pressurized gas inflow method, cleaning method, and introduction force of standard breathing gas (10
) The method and effect are exactly the same as the embodiments in Figures 1 and 2.

FIG. 4 shows the results of measuring trace amounts of acetone contained in human exhaled breath collected by the exhaled breath sampling device according to the present invention. For comparison, the results of acetone in exhaled breath collected and measured using conventional device 2) are also shown. The solid line is the result according to this example, and the broken line is the result according to the conventional device. The internal volumes of the sample gas storage bag of the exhaled breath sample collection device according to the present invention and the conventional device used in this case were both 5 tons, and the sample gas introduction rate into the atmospheric pressure ion source was both 200 mL and 1 minute. As is clear from the figure, the acetone concentration decreases with the conventional device as the measurement time passes, and no decrease in acetone concentration is observed with the exhaled breath sample collection device of the present invention. Acetone is an important substance as an indicator of fat metabolism and diabetes. As with conventional devices, when the concentration of trace components contained in exhaled air changes, when a mass spectrum is measured by performing a mass scan from the low mass side to the high mass side, the peak on the high mass side will be low (11) on the mass side. It is not possible to obtain a correct spectrum because the peak is affected more by concentration changes than the peak. The slower the scanning speed is in order to reduce the influence of noise and detect weak and small peaks of trace components, the greater this influence becomes. As described above, according to this embodiment, it is possible to more accurately detect trace amounts of organic substances contained in exhaled breath due to important biological metabolism.

〔Effect of the invention〕

As described above, according to the present invention, regarding the measurement of trace metabolites in exhaled breath, which allows biological metabolites to be measured non-invasively, mixing of the sample gas led to the atmospheric pressure ion source and the pressurized gas does not occur. , it is possible to eliminate the influence of concentration changes due to gas mixing on trace metabolites, and has the effect of obtaining accurate spectra.

With conventional equipment, in order to eliminate concentration changes due to gas mixing, it is necessary to move the subject to the installation location of the atmospheric pressure ionization mass spectrometer, and when moving the sample without moving the subject, the effect of concentration changes due to gas mixing must be removed. was there. In the present invention, the sample can be moved (12) and is not affected by the l# degree change due to gas mixing. Furthermore, in the conventional apparatus, a pressurized gas is mixed with a sample gas, but since the measurement targets trace components of ppb or less, an extremely high purity gas is required as the pressurized gas, which is expensive. In the present invention, since gas mixing does not occur, the purity of the pressurized gas does not matter and the gas cost is low.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the sample gas sampling device according to the first embodiment of the present invention as seen from the front, and FIG. 2 is a cross-sectional view of the sample gas sampling device of FIG. 1 when combined with an atmospheric pressure ionization mass spectrometer. 3 is a cross-sectional view of the sample gas sampling device of the second embodiment, and FIG. 4 is a cross-sectional view of the sample gas sampling device of the second embodiment, and FIG. It is a figure which shows the result of measuring contained acetone with an atmospheric pressure ionization quality meter analyzer. DESCRIPTION OF SYMBOLS 1... Inner bag for sample gas storage, 2... Outer bag for pressurized gas inflow, 3... Gas inlet/outlet, 4... Nut, 5...
Gas inlet/outlet, 6...Packskin, 7...Pressurized gas inlet, 8...Connection (13) combined volume, 9...Mouthpiece, 10...Cap, 1
DESCRIPTION OF SYMBOLS 1... Cap, 12... Valve, 13... Valve, 14... Coupler, 15... Atmospheric pressure ion source, 1
6... Atmospheric pressure ionization mass spectrometer analysis section, 17...
Flowmeter, 18... Sample introduction tube, 19... Sample gas storage bag, 20... Pressurized gas inflow tube, 21... Plastic film, Fig. 1 Fig. 2 Fig. 3 Fig. tθ Z 4 Zusoku Kajikisaki)

Claims (1)

[Scope of Claims] 1. A sample gas storage chamber having an inlet for introducing a breath sample, an opening for introducing a breath sample into a measuring device or a wash gas, and a sample adjacent thereto. A sample gas sampling device comprising a pressurized gas chamber having a pressurized gas inlet for introducing gas. 2. The sample gas sampling device according to claim 1, wherein the sample gas storage chamber and the pressurized gas chamber are flexible plastic bag-like containers. 3. The sample gas sampling device according to claim 1 or 2, wherein the sample gas inlet has an inner diameter of 7 mm or more.