JP4210181B2 - Exhalation component analyzer - Google Patents

Description

  The present invention relates to a breath component analyzer.

  Conventionally, gas chromatograph devices that perform qualitative and quantitative analysis of components in gas have been widely used. This is done by introducing the gas to be measured together with the carrier gas into the gas separation column packed with the packing material. The components contained in the gas are separated by the retention time difference due to the interaction with the packing material in the gas separation column, and the separated components in the gas are derived from the gas separation column, and a thermal conductivity detector (TCD) A chromatogram is obtained by detecting with a detector such as a flame ionization detector (FID).

  FIG. 11 shows an example of such a conventional gas chromatograph device 6. After the carrier gas supplied from the gas cylinder 7 via the gas flow path 8 is adjusted in flow rate by the flow rate regulator 9, the flow rate sensor is shown. The flow rate is detected at 10 and further mixed with the measurement gas injected from the gas injection port 11 of the measurement gas and introduced into the gas separation column 1.

  At this time, since the retention time of the components in the gas in the gas separation column 1 depends on the temperature, the gas separation column 1 is placed in the thermostat 40 and is heated and held at a constant temperature. Accurate measurement is performed by keeping the retention time of the components in the gas constant. The gas derived from the gas separation column 1 is detected by the detector 14, and a chromatogram is obtained.

  The thermostatic chamber 40 is configured by providing a heater 41 and a fan 42 in a housing, and further providing an intake port 43 and an exhaust port 44 whose opening amounts can be adjusted in the housing. When the temperature of the heater is increased, the heater 41 is energized and the fan 42 is rotated to send the air heated by the heater 41 to the gas separation column 1. The temperature is adjusted by adjusting the opening amount of 44. Further, when the gas separation column 1 is cooled, the fan 42 is rotated with the opening amounts of the intake port 43 and the exhaust port 44 being maximized, and the outside air is circulated in the constant temperature bath 40.

  In the conventional gas chromatograph 6, the thermostat 40 as described above is provided to heat and hold the gas separation column 1 at a constant temperature, and the thermostat 40 having such a configuration is difficult to downsize, The entire apparatus was also increased in size.

  On the other hand, in the medical field, the introduction of an exhalation component analyzer using a gas chromatograph device is being studied for the purpose of finding diseases and confirming therapeutic effects by component analysis of exhaled gas. There is a need for a breath component analyzer.

  Corresponding to this, the present inventors have already proposed a gas separation column 1 having a rubber heater 2 closely arranged on the outer surface as shown in FIG. 12 (see, for example, Patent Document 1). ). This gas separation column 1 includes an outer cylinder 1a made of a metal having high thermal conductivity such as stainless steel and copper, and an inner cylinder 1b made of, for example, Teflon (R) inserted into the outer cylinder 1a. The inner cylinder 1b is filled with a filler serving as a stationary phase. As this filler, an appropriate material is used according to the type of expiration gas or carrier gas to be detected. The rubber heater 2 is a flexible heater in which a resistor 3 is insulated with an insulating rubber such as a silicone rubber sheet. The resistor 3 spirals from one end side to the other end side on the outer peripheral surface of the gas separation column 1. The gas separation column 1 is arranged in close contact with the outer surface of the gas separation column 1. The gas separation column 1 is provided with a temperature sensor 4 made of a thermocouple, and the thermocouple is covered with an insulating material such as a polyfluorinated ethylene resin (Teflon (R), etc.) or glass wool. In this state, the gas separation column 1 is disposed on the outer surface, and the temperature sensor 4 detects the temperature of the gas separation column 1.

  An example of an exhalation component analyzer A using this gas separation column 1 is shown in FIG. In FIG. 13, a cooling fan 12 is disposed in the vicinity of the gas separation column 1.

  In addition, a temperature controller 13 that operates according to a setting operation in a column heating temperature adjustment panel (not shown) is provided in the expiration component analyzer A, and the detection result by the temperature sensor 4 is input to the temperature controller 13. The energization amount in the heater 2 and the driving of the cooling fan 12 are controlled by the temperature controller 13 based on the detection result by the temperature sensor 4.

  Next, the operation of the breath component analyzer A shown in FIG. 13 will be described. First, the power is turned on to set the start of the measurement operation. When the carrier gas is supplied from the gas cylinder 7 into the gas flow path 8 and the expiratory gas as the measurement gas is injected from the gas inlet 11, After the flow rate of the supplied carrier gas is adjusted by a flow rate regulator 9 such as a needle valve, and the flow and flow rate of the carrier gas are confirmed by detection by the flow rate sensor 10, the exhaled air supplied from the gas inlet 11 A gas is mixed with the carrier gas. This mixed gas is introduced into the gas separation column 1, passes through the stationary phase inside the gas separation column 1, and thereby the components in the gas are separated by interaction with the stationary phase, and is derived from the gas separation column 1. Next, the components in the gas derived from the gas separation column 1 are detected by the detector 14, and this detection information is input to the control unit 15 to be analyzed and a chromatogram is obtained. It is displayed on the display unit 16.

  During the measurement operation, the gas separation column 1 is heated by energizing the heater 2 so as to reach a predetermined temperature under the control of the temperature controller 13. At this time, the temperature controller 13 controls the energization amount to the heater 2 based on the detection result by the temperature sensor 4, and drives the fan 12 as necessary, thereby bringing the gas separation column 1 to a predetermined temperature. Keep heated. Therefore, accurate measurement is performed while keeping the retention time of the components in the gas in the gas separation column 1 constant.

As described above, since the gas separation column 1 used in the breath component analyzer A shown in FIG. 13 is heated and held by the heater 2 as described above, a large-scale apparatus configuration like the conventional thermostatic bath 40 is required. Thus, the structure of the heating means for heating and holding the gas separation column 1 at a constant temperature can be reduced, and the entire apparatus can be reduced in size.
JP 2003-57222 A

  In the exhalation component analyzer described above, the type of the gas component contained in the exhalation gas is determined based on the peak retention time appearing in the detection output of the detector 14, so the retention time is the same or close. However, there is a problem that the type of gas component cannot be determined.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an expiration component analyzer that can determine the type of gas component even when the retention time (retention time) is the same or close. It is to provide.

  In order to achieve the above object, the invention of claim 1 is directed to a gas separation column filled with a member that causes a flow delay in accordance with a gas component, and expiratory gas is introduced into the gas separation column from the intake side of the gas separation column. An expiratory gas supply means for supplying a carrier gas, a semiconductor gas sensor, a detection means provided on the exhaust side of the gas separation column for detecting a gas component of the expiratory gas that sequentially appears on the exhaust side; Retention times of a plurality of types of gas components to be detected included in the gas, a peak waveform of detection output of the detection means for each of the plurality of types of gas components, and each gas component corresponding to an output value of the detection output of the detection means The storage means in which the concentration data of each is registered in advance and each of one or more peaks appearing in the detection output of the detection means based on the data registered in the storage means. The gas component type is identified by comparing the peak waveform of the gas component whose appearance time is approximately equal to the appearance time of each peak, and the gas component gas is determined from the concentration data of each gas component corresponding to the output value of the detection output. And gas component measuring means for measuring the concentration.

  According to a second aspect of the present invention, in the first aspect of the invention, the means for correcting the variation in the retention time of the gas component to be detected contained in the expiratory gas on the basis of the variation in the retention time of the invariant component contained in the expiratory gas. It is characterized by comprising.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the expiratory gas supply means pressure-feeds air from the intake side of the gas separation column into the gas separation column via a gas flow path using air as a carrier gas. A pump, a gas supply port provided in the gas flow path between the air pump and the gas separation column, for supplying exhaled gas into the carrier gas in the gas flow path, and upstream of the gas supply port And a buffer tank that holds a predetermined amount of carrier gas sufficiently larger than the amount of carrier gas per unit time that the air pump supplies to the gas separation column.

  According to a fourth aspect of the present invention, there is provided the gas flow according to the first or second aspect, wherein the expiratory gas supply means includes a connecting portion that is closed when not connected, and one end is connected to the intake side of the gas separation column. By connecting and communicating with the other end of the path, a variable volume bag-like tank for supplying a carrier gas sealed inside to the gas flow path side, and an exhaust side of the gas separation column are provided, and an intake air of the gas separation column is provided. An air pump for suction that makes the exhaust side negative with respect to the side, a gas supply port that is provided between the intake side of the gas separation column and the bag-like tank, and supplies exhaled gas into the carrier gas; It is characterized by comprising.

  According to a fifth aspect of the invention, in the third aspect of the invention, the intake side of the buffer tank is opened to the atmosphere, the exhaust side is connected to the intake side of the air pump, and the air pump is moved to the gas separation column side. A gas flow path is provided between the exhaust side of the air pump and the buffer tank to return excess carrier gas exceeding the necessary carrier gas flow to be supplied to the buffer tank.

  According to a sixth aspect of the present invention, in the third or fourth aspect of the present invention, a gas purification apparatus using either one or both of a gas adsorbing material and a gas decomposition catalyst as a gas purification material is a gas upstream of the gas supply port. It is provided in the flow path.

  According to a seventh aspect of the present invention, in any one of the third to sixth aspects of the present invention, a flow rate for detecting a flow rate in a gas flow path near the upstream of the gas supply port or a gas flow path near the downstream of the detection means. It is characterized by comprising a sensor and means for detecting the supply of exhaled gas based on a change in the detection output of the flow sensor.

  According to an eighth aspect of the present invention, in the seventh aspect of the invention, there is provided means for changing the flow rate of the carrier gas supplied to the gas separation column so as to improve the gas separation efficiency and shorten the analysis time after detecting the supply of the expiration gas. It is characterized by having.

  As described above, in general gas chromatographs, if the retention time is the same, it is impossible to identify the type of gas component. However, if the detection means is a semiconductor gas sensor, the peak waveform of the detection output Is an asymmetric waveform, and the peak waveform differs depending on the type of gas component. In the first aspect of the present invention, the retention time corresponds to the appearance time of each peak. Since the types of gas components are identified by collating peak waveforms of substantially equal gas components, the types of gas components can be reliably identified even when the retention time is the same, and the output value of the detection output The gas concentration of each gas component can be measured from the corresponding concentration data of each gas component.

  According to the second aspect of the present invention, even when the flow rate of the carrier gas varies, the retention time of the gas components in the expiration can be corrected, and as a result, the gas components in the expiration can be analyzed.

  In the invention of claim 3, even if the miscellaneous gas component is contained in the carrier gas composed of the air sucked by the air pump, the miscellaneous gas component can be diluted by the buffer tank and sent to the gas separation column. Therefore, it is possible to provide a breath component analyzer that can suppress the fluctuation in the baseline of the detection output of the detection means caused by the above, and can perform highly reliable measurement with less influence on the component analysis due to the fluctuation in the baseline.

  In the invention of claim 4, it is possible to send only clean air as a carrier gas to the gas separation column, so that it is possible to eliminate the fluctuation in the baseline of the detection output of the detection means caused by the influence of the miscellaneous gas, As a result, there is no influence on the component analysis due to the fluctuation of the baseline, and it is possible to provide a breath component analyzer that can perform highly reliable measurement.

  In the invention of claim 5, it is possible to use a general-purpose inexpensive air pump having a large intake amount compared to the flow rate of the carrier gas fed into the gas separation column, and returning the excess gas to the buffer tank. The load of the air pump can be reduced and the life of the air pump can be extended.

  According to the sixth aspect of the present invention, even when a high-concentration miscellaneous gas is contained in the atmosphere or when the miscellaneous gas exists in the atmosphere for a long time and cannot be fully diluted in the buffer tank, it remains in the carrier gas. The miscellaneous gases that are present can be reliably removed, and as a result, the baseline can be prevented from fluctuating due to these miscellaneous gases.

  According to the seventh aspect of the present invention, it is possible to automatically detect the timing of exhalation gas injection as a reference for determining the retention time, and as a result, to reliably determine the retention time of the gas component of the exhalation gas, and to analyze the gas component with reliability. Can be high.

  In the invention of claim 8, even for a gas component with a slow retention time, the detection time can be shortened to sharpen the peak of the detection output, and the concentration conversion can be made accurate.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 2 shows a flow path configuration diagram of the exhalation component analyzer A of the present embodiment. In this embodiment, when the intake port 20a consisting of a small hole communicating with the atmosphere is opened, the exhaust port 20b and the return port 20c. A bottle-shaped buffer tank 20 having an opening, an air pump P connected to the exhaust port 20b via a gas flow path 21, and an air pump P that is sucked from the atmosphere via the buffer tank 20 and pressurized. The inserted air is inserted between the gas separation column 1 where the carrier gas is pumped through the gas passage 22 and the gas passage 22 from the exhaust side of the air pump P to the intake side of the gas separation column 1. The gas purifier 23, a flow rate regulator 24 comprising a needle valve inserted between the gas flow path 22 from the exhaust side of the gas purifier 23 to the intake side of the gas separation column 1, and a gas flow A flow rate sensor 25 provided for detecting a pressure change in the gas inlet 22 and a gas inlet 26 provided on the intake side of the gas separation column 1 for injecting and supplying an exhaled gas, which is a gas to be measured, into the carrier gas; The branch part 27 provided with the gas flow path 22 from the exhaust side of the air pump P to the gas purification device 23, and the return gas flow path 29 and the branch part 27 connected to the return port 20c of the buffer tank 20 A flow rate regulator 28 for controlling the flow velocity inserted between them and a detector 30 comprising a semiconductor gas sensor is provided in the exhaust port communicating with the atmosphere of the gas separation column 1.

  Here, since the carrier gas flowing through the gas separation column 1 is about 10 cc / min, in this embodiment, a buffer tank 20 having a sufficiently large capacity compared to the flow rate, for example, a tank of about 1000 cc, is used. Is diluted with the air in the buffer tank 20 to suppress the fluctuation in the baseline of the detection output of the detector 30.

  The gas purifying device 23 is used to remove the miscellaneous gas when the high concentration miscellaneous gas in the atmosphere or the miscellaneous gas contained in the atmosphere cannot be diluted in the buffer tank 20 over a long period of time. One or both of a gas adsorbing substance such as activated carbon and silica gel, and a gas decomposition catalyst such as an oxidation catalyst are used. In particular, as the gas decomposition catalyst, a combustion catalyst carrying a noble metal catalyst such as platinum or platinum palladium (heated to 150 ° C. to 200 ° C. with a heater or the like) is used, and any structure such as a honeycomb structure or a granular shape may be used. When the gas adsorbing material is used alone, the gas adsorbing material is not limited to the position shown in FIG. 2 and may be provided between the buffer tank 20 and the air pump P or upstream of the buffer tank 20. Further, when a gas decomposition catalyst (combustion catalyst) is used alone or in combination with a gas adsorbing substance, it is preferably provided between the buffer tank 20 and the air pump P. The gas decomposition catalyst may be provided at any location as long as it is upstream of the gas inlet 26, and the gas purification devices 23 may be provided at a plurality of locations.

  Further, the gas separation column 1 having the structure shown in FIG. 12 described above is used to reduce the size of the breath component analyzer A.

  FIG. 1 shows a circuit configuration diagram of this embodiment. In this block, a power supply unit 31, a column heater control unit 32, an arithmetic processing unit 33, a display unit 34, and a flow rate measurement unit 35 are provided. 31 has a function of generating a power supply voltage for driving the air pump P and an operation power supply voltage + V for each of the units 33 to 35 from an AC power supply when a power switch (not shown) is turned on.

  In the column heater control unit 32, the PID control unit 32a controls the energization power of the heater 2 through the phase control unit 32b based on the temperature of the heater 2 wound around the gas separation column 1 based on the temperature detected by the temperature sensor 4 including a thermistor. The temperature of the gas separation column 1 is kept at a predetermined temperature set in advance.

  The arithmetic processing unit 33 receives the detection output of the flow sensor 25 from the flow measurement unit 35, detects a change in the flow rate based on the detection output, and detects the injection timing of the expiration gas from the gas inlet 26 by this detection. A calculation function for calculating the flow rate of the carrier gas in the gas flow path 22 based on the processing function and the detection output of the flow sensor 25, and the temperature cycle of the detector 30 by controlling the energization of the heater 30a of the detector 30 comprising a semiconductor gas sensor. Further, a control function for alternately setting a high temperature period for heat cleaning of the gas sensitive body of the detector 30 and a low temperature period that is a period for taking in the detection output of the gas sensitive body, and a detection output and an injection timing captured in the low temperature period Analysis processing function for analyzing and quantitatively determining the detected gas component based on the detection of gas, and the temperature sensor for the temperature of the gas separation column 1 Together and a function of determining from the detection signal, and a function of displaying data transmitted to the display unit 34.

  The display unit 34 includes a liquid crystal display and a controller. Based on display data from the arithmetic processing unit 33, the flow rate of the carrier gas, the analysis result and quantitative value of the detected gas component obtained by the analysis processing function, and the gas separation column 1 The temperature is displayed.

  The flow sensor 25 is configured using a wind speed sensor including a negative characteristic thermistor and a platinum coil. The flow sensor 25 is disposed so that the platinum coil and the negative characteristic thermistor face the gas flow path 22, and a voltage is applied to the platinum coil disposed on the upstream side to cause the carrier gas in the gas flow path 22 to flow. Heat. The temperature of the carrier gas heated by the platinum coil is detected by a negative characteristic thermistor. When a certain amount of carrier gas is flowing in the gas flow path 22, the temperature detected by the negative characteristic thermistor is a constant temperature. However, when the flow rate (flow velocity) of the carrier gas changes, the detection temperature changes, and when the flow rate stabilizes thereafter, the detected temperature is maintained at a constant temperature corresponding to the flow rate (flow velocity). After A / D conversion, the data is taken into the arithmetic processing unit 33, and the arithmetic processing unit 33 monitors the flow rate of the carrier gas by converting the detected temperature into the flow rate.

  Thus, when the power switch is turned on to operate the exhalation component analyzer A, the air pump P sucks air from the atmosphere via the buffer tank 20, and uses the sucked air as a carrier gas via the branch portion 27. Then, the pressure is fed to the gas flow path 22 side by the flow rate adjusted by the flow rate regulator 24. At this time, excess carrier gas, which is air, is returned to the buffer tank 20 via the flow rate regulator 28 and the return gas passage 29.

  On the other hand, the carrier gas sent to the gas flow path 22 side passes through the gas purification device 23, so that miscellaneous gas components that cannot be diluted in the buffer tank 20 are removed, and the gas is supplied as a clean carrier gas via the flow rate regulator 24. It is sent to the separation column 1 and finally released into the atmosphere.

  The flow rate of the carrier gas is constantly detected by the flow rate sensor 25 described above, and the arithmetic processing unit 33 converts the flow rate to the flow rate as described above based on the detection output of the flow rate sensor 25, and the conversion result is displayed by the display unit 34. indicate.

  When a driving operation for injecting an exhalation gas to be detected into the gas injection port 26 is performed in a state where the carrier gas is being sent into the gas separation column 1 in this way, the exhalation gas is injected, thereby causing a gas flow path. The flow velocity (flow rate) in 22 decreases instantaneously.

  This instantaneous decrease instantaneously increases the temperature detected by the negative characteristic thermistor of the flow sensor 25. This instantaneous change in the detected temperature is detected by the arithmetic processing unit 33 by comparing the level of the detection output B of the flow sensor 25 shown in FIG. 3 with a preset reference level L, and at the detected timing It is determined that gas has been injected, and the retention time of the gas component detected by the detector 30 is measured based on this timing. In other words, in the present embodiment, the detection of the timing for injecting the exhalation gas was performed by the manual switch operation by the operator, but in this embodiment, the detection can be performed accurately.

Here, in the case where a disease is discovered from the gas component contained in the exhalation gas using the exhalation component analyzer A of the present embodiment or the therapeutic effect is confirmed, the type of the gas component to be detected depends on the type of the disease or treatment. For example, in diabetic patients, liver disease patients, and alcohol-administered patients, for example, by detecting acetone, CH ₃ SH, and CS ₂ in exhaled gas, the detection of disease and the effect of treatment can be achieved. Useful for confirmation. Therefore, in this apparatus, the memory 33a of the arithmetic processing unit 33 corresponds to the retention times of a plurality of types of gas components to be detected included in the expiration gas, and the peak value of the detection output of the detector 30 for each of the gas components. Calibration curve data (see FIG. 4) indicating the concentration data of each gas component, and data of a normalized curve indicating the peak waveform for each gas component when the peak value of the detection output of the detector 30 is “1” (FIG. 4). 5) is registered in advance.

In FIG. 4, when the horizontal axis is the gas concentration (ppb) and the vertical axis is the output change (mV) of the detector 30, the output Y of the detector 30 is expressed as Y = aX ^ b. In FIG. 4, straight line I represents acetone, straight line II represents CH ₃ SH, and straight line III represents CS ₂ . In the calibration curve data of FIG. 4, the calibration curve is obtained by the peak height, but the peak area may be used instead of the peak height.

In addition, the peak curve C in FIG. 5 is invariable components (components that become the background of exhalation) such as CO ₂ and O ₂ contained in exhaled air, peak curve D is acetone, and peak curve E is CH _3. The SH and peak curve F correspond to CS ₂ and the time when each peak is reached is the retention time.

  Accordingly, the arithmetic processing unit 33 determines the time (appearance) from the gas injection timing to the generation timing of each peak for one or more peaks appearing in the detection output of the detector 30 that detects the gas exiting the gas separation column 1. Time) to measure the retention time of the detected gas component, determine the detected gas component by comparing the retention time and the waveform shape of the detected peak with the data registered in the memory 33a, Further, the concentration (quantitative value) of the detected gas component is determined from the peak value of the detection output at that time, and the determination result is displayed on the display unit 34.

  Here, in the data stored in the memory 33a of the arithmetic processing unit 33, when the peak waveform of the detection output of the detector 30 with respect to the gas component to be detected included in the exhalation gas, that is, the peak value of the detection output is 1. The standardized curve data indicating the peak shape is particularly necessary when the detector 30 is composed of a semiconductor gas sensor. In a normal gas chromatograph device in which the detector 30 is configured by PID (photoionization detector) or FID (hydrogen flame ionization detector), the peak waveform of the detection output is a normal distribution curve (Gaussian curve) as shown in FIG. Become. This is because the gas components injected into the gas separation column 1 are normally distributed in the carrier gas, and the gas concentration reaching the detector 30 also increases or decreases according to the normal distribution. Therefore, the outputs of the physical sensors PID and FID are This is because the output follows the change in gas concentration. However, when the detector 30 is configured by a semiconductor gas sensor, the peak waveform of the detection output of the detector 30 may not be a normal distribution curve. The reason is the adsorption and desorption speed of the surface of the semiconductor gas sensor and the gas component to be detected. That is, in the semiconductor gas sensor, the gas is detected by utilizing the chemical change between the surface and the sample gas, and the reaction rate differs between the time of gas adsorption and the time of gas separation and also differs depending on the gas type. As can be seen from the normalized curve in FIG. 5, when the gas concentration of the gas component reaching the detector 30 increases, that is, when the gas adsorption occurs, the reaction is rapid, and the gas component reaching the detector 30 The detection output changes following the gas concentration change, but when the gas concentration decreases, that is, when the gas is released, the reaction speed is slow, so the output change of the detector 30 follows the gas concentration change. It cannot be done and appears as tailing. Further, the waveform of the detection output varies depending on the gas type, and the tailing is very large in the waveforms of C and F in FIG. In general, the longer the holding time (retention time), the broader the detection output peak. However, the waveform of the gas F has a broader peak than the waveform of the gas D having a longer holding time than F. This is also because the reaction of the gas F on the gas sensor surface is slow.

  Thus, the peak waveform of the detection output for each gas component of the detector 30 is not a normal distribution curve, and the peak waveform differs depending on the type of gas component. In order to separate and accurately detect these gas components, it is necessary to register the peak waveform of the detection output in the memory 33a for each of the gas components to be detected.

Thus, the arithmetic processing unit 33 collates the retention time of the detection output peak with the retention time data of each gas component registered in the memory 33a, and registers the detection output peak in the memory 33a. The peak waveform data is collated, and by using the retention time collation and the peak waveform collation together, the type of gas component can be specified, and the gas value can be determined from the peak value or area of the detected output at this time. The concentration (quantitative value) of the component is obtained. When calculating the peak value or area of the detection output of each gas component, the sum of the peak value or area of each detection output is the detection output of the detector 30. The peak value or area of the detection output of each gas component is determined so as to match the waveform data. Here, a in FIG. 7A is a waveform of the detection output of the detector 30, and c, d, e, and f in FIG. 7C are invariant components such as CO ₂ and O ₂ obtained by arithmetic processing, Each separation waveform of acetone, CH ₃ SH, and CS ₂ , and b in FIG. 4B, are the waveforms obtained by adding the separation waveforms c, d, e, and f, and the synthesis of the actual detection output waveform a and the separation waveform. It is in good agreement with the waveform b. Further, the separated waveforms c, d, e, and f in FIG. 7 are in good agreement with the standardized curves C, D, E, and F in FIG. 5 registered in the memory 33a.

By the way, when the flow rate of the carrier gas changes for some reason, the retention time fluctuates, and the analysis processing and the like become uncertain. Therefore, paying attention to the fact that the gas component in which the peak of the detection output of the detector 30 first appears is an invariant component included in any exhalation such as CO ₂ , O _2, etc., based on the retention time of this gas component, The calculation processing unit 33 calculates how much the retention time corresponding to the peak of the detection output that appears thereafter deviates from the reference, and based on the calculation result, the above-described H ₂ S, CH ₃ SH, (CH ₃ ) By correcting the ₂ S retention time, the influence of the flow rate variation of the carrier gas may be removed.

(Embodiment 2)
In the first embodiment, the buffer tank 20 is provided on the upstream side of the air pump P, and the excess air is returned to the buffer tank 20. However, in the present embodiment, the buffer tank 20 is used as the flow regulator 24 as shown in FIG. Is inserted into the gas flow path 22 between the gas inlet 26 and the air pump P, and the air pump P directly sucks air from the intake side, adjusts the flow rate of the sucked air by the flow rate regulator 24, and then uses the buffer tank 20 as a carrier gas. In this way, the gas separation column 1 is fed through. When the air pump P has a large intake capacity, excess air is discharged to the atmosphere. Of course, the buffer tank 20 may be provided upstream of the air pump P.

  Since other configurations are the same as those in the first embodiment, illustration and description thereof are omitted.

(Embodiment 3)
By the way, since the above-mentioned retention time depends on the carrier gas flow rate, naturally, the higher the carrier gas flow rate, the faster the retention time, and depending on the gas component, there are cases where the time taken out from the gas separation column 1 is very slow. In such a case, it takes time and the peak of the detection output becomes broad, resulting in inaccurate concentration conversion.

  Therefore, in the present embodiment, control is performed to increase the flow rate of the carrier gas in a predetermined pattern from the time of the gas injection detection in order to make the detection time of the gas type having a low retention time early and sharpen the peak of the detection output. It is a thing.

  FIG. 9 is a flow path configuration diagram in the present embodiment, in which a flow path 22a in which a flow rate regulator 24a for adjusting a flow rate and an electromagnetic valve 37a are inserted, a flow rate regulator 24b for adjusting a flow rate, and an electromagnetic valve 37b are inserted. Provided in the gas flow path 22 so as to be parallel to the flow path 22b, one flow path 22a is used as a flow path for supplying a predetermined carrier gas flow rate before injecting exhalation gas, and the other flow path 22b is used as the exhaled gas. After the injection, it is used as a channel for increasing the carrier gas. The flow rate adjusters 24a and 24b are adjusted in advance so that the flow rate becomes a predetermined flow rate, and the arithmetic processing unit 33 controls the opening of the electromagnetic valve 37a and the closing of the electromagnetic valve 37b in the normal state, and at the time of detecting the expiration gas injection The electromagnetic valve 37a is closed and the electromagnetic valve 37b is opened along the flow rate change pattern registered in advance in the memory 33a to control the flow rate of the carrier gas.

  Here, the flow paths 22a and 22b may be inserted into the gas flow path 21 between the buffer tank 20 and the air pump P. Also, by controlling the applied voltage of the air pump P to increase the amount of air intake from the atmosphere, the flow rate regulator 24 is replaced with a needle valve that can be electrically controlled, and the flow rate adjustment amount of the flow rate regulator 24 is switched. The flow rate of the carrier gas may be controlled. In this case, if the applied voltage of the air pump P is gradually increased by an inverter device or the like, the flow rate of the carrier gas can be gradually increased.

  The configuration of the present embodiment is similar to that of the first or second embodiment, and illustration and description of other configurations are omitted.

(Embodiment 4)
Each of the first to third embodiments is based on the premise that the buffer tank 20 is used. However, as shown in FIG. 10, clean carrier gas air is sealed in a variable-capacity bag-like tank 39 such as a rubberized bag. In using the breath component analyzer A, the connection part 39a provided at the exhaust port of the bag-like tank 39 is connected to the connected part provided at one end of the gas flow path 22 so that the inside of the bag-like tank 39 And the gas flow path 22 side are connected, and the carrier gas in the bag-like tank 39 is sucked into the gas separation column 1 together with the exhalation gas by the suction air pump P provided on the exhaust side of the gas separation column 1. This embodiment has a feature.

  Here, a gas supply port (hereinafter referred to as a gas suction port) 26 ′ is provided so as to communicate with the gas flow path 22 via an electromagnetic valve 38. The suction port 26 ′ is open to the atmosphere, and when the electromagnetic valve 38 is opened by turning on a manual switch or the like, the atmosphere gas as the gas to be measured is sucked into the gas flow path 22 which is in a negative pressure, and the carrier gas At the same time, it is supplied into the gas separation column 1.

  On the other hand, the connection part 39a of the bag-like tank 39 has an open / close valve structure in which the exhaust port is closed and the internal air does not leak outside when not connected to the gas flow path 22, and communicates as described above when connected. The tank 39 is removed when the apparatus is not used. In addition, when measuring components of exhaled gas, the exhaled gas may be put in a bag or the like and connected to the gas suction port 26 '.

  Since the configurations of Embodiments 1 to 4 may be used other than the above configuration, illustration and description are omitted here.

It is a channel lineblock diagram of Embodiment 1 of the present invention. It is a circuit block diagram same as the above. It is explanatory drawing of a to-be-measured gas injection | pouring detection same as the above. It is explanatory drawing of the calibration curve used for the same as the above. It is explanatory drawing of the normalization curve used for the same as the above. It is explanatory drawing of the normalization curve represented by a normal distribution curve. (A)-(c) is a chromatograph of the example of a measurement in the breath component analysis apparatus using the same as the above. It is a channel block diagram of Embodiment 2 of the present invention. It is a flow-path block diagram of Embodiment 3 of this invention. It is a flow-path block diagram of Embodiment 4 of this invention. It is a block diagram of the conventional gas chromatograph apparatus. It is a perspective view of an example of a gas separation column. It is a block diagram of the conventional breath component analyzer using the gas separation column same as the above.

Explanation of symbols

1 Gas Separation Column 30 Detector 33 Arithmetic Processing Unit 33a Memory

Claims (8)

A gas separation column packed with a member that causes a flow delay according to the gas component;
Expiratory gas supply means for supplying a carrier gas containing expiratory gas into the gas separation column from the intake side of the gas separation column;
A detection means configured using a semiconductor gas sensor, provided on the exhaust side of the gas separation column, for detecting a gas component of expiratory gas that sequentially appears on the exhaust side;
Retention times of a plurality of types of gas components to be detected contained in exhaled gas, peak waveforms of detection outputs of detection means for each of the plurality of types of gas components, and the respective gases corresponding to output values of detection outputs of detection means Storage means in which component concentration data is registered in advance;
By comparing the peak waveform of the gas component whose retention time is substantially equal to the appearance time of each peak with each of one or more peaks appearing in the detection output of the detection means based on the data registered in the storage means, the gas component And a gas component measuring means for measuring the gas concentration of each gas component from the concentration data of each gas component corresponding to the output value of the detection output. .   2. The apparatus according to claim 1, further comprising means for correcting a variation in the retention time of the gas component to be detected contained in the expiration gas with reference to a variation in the retention time of the invariant component contained in the expiration gas. Exhalation component analyzer.   The expiratory gas supply means uses air as a carrier gas to pump the gas separation column from the intake side into the gas separation column through a gas flow path, and the air pump between the air pump and the gas separation column. A gas supply port provided in the gas flow path for supplying an exhalation gas into the carrier gas in the gas flow path, and provided on the upstream side of the gas supply port, and the air pump supplies the gas separation column The breath component analyzing apparatus according to claim 1 or 2, comprising a buffer tank that holds a predetermined amount of carrier gas that is sufficiently larger than the amount of carrier gas per unit time.   The expiratory gas supply means includes a connection portion that is closed when not connected, and is connected to the other end of the gas flow path having one end connected to the intake side of the gas separation column, thereby sealing the carrier sealed inside A variable-capacity bag-like tank for supplying gas to the gas flow path side, and an air pump for suction that is provided on the exhaust side of the gas separation column and makes the exhaust side have a negative pressure with respect to the intake side of the gas separation column And a gas supply port that is provided between an intake side of the gas separation column and the bag-like tank and supplies an exhaled gas into a carrier gas. Exhalation component analyzer.   The intake side of the buffer tank is opened to the atmosphere, the exhaust side is connected to the intake side of the air pump, and excess carrier gas exceeding the necessary carrier gas flow rate supplied to the gas separation column side by the air pump is supplied to the buffer. 4. The breath component analyzing apparatus according to claim 3, wherein a gas flow path returning to the tank is provided between an exhaust side of the air pump and the buffer tank.   5. A gas purification device using either or both of a gas adsorbing material and a gas decomposition catalyst as a gas purification material is provided in a gas flow path upstream of the gas supply port. The breath component analysis apparatus described.   A gas flow sensor for detecting a flow rate is provided in a gas flow channel in the vicinity of the upstream of the gas supply port or in the gas flow channel in the vicinity of the downstream of the detection means. The breathing component analyzer according to any one of claims 3 to 6, further comprising a detecting unit. 8. The breath according to claim 7, further comprising means for changing the flow rate of the carrier gas supplied to the gas separation column so as to improve the gas separation efficiency and shorten the analysis time after detecting the supply of the breath gas. Component analyzer.

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