JPH1062403A - Analysis of pentane in exhalation and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To analyze pentane only slightly contained in exhalation by passing an exhalation sample through a capillary column by carrier gas to detect pentane separated by the capillary column. SOLUTION: A capillary column 12 has a coating layer composed of an inactive porous polymer on its inner wall surface and allows an exhalation sample A to pass to separate pentane contained in the exhalation sample A. A conc. sample introducing part 16 desorbs the exhalation sample A adsorbed on the inside of a collection pipe 14. A carrier gas control part 18 allows the exhalation sample A desorbed by the conc. sample introducing part 16 to pass through a capillary column 12 by carrier gas C. A detector 20 detects pentane separated by the capillary column 12. Herein, by optimizing analyzing conditions such as the length and temp. of the capillary column 12 and the flow rate of the carrier gas C, the detection accuracy of pentane can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for analyzing pentane in exhaled breath for analyzing pentane contained in exhaled breath using gas chromatography in the medical field.

[0002]

2. Description of the Related Art Conventionally, as described in, for example, JP-A-6-58919, a breath analyzer for collecting and analyzing the breath of a subject has been developed. Breath analyzers are, for example, breath analysis for clinical tests in the medical field and monitoring of patient condition, measurement of work environment and indoor environment in the industrial field, drunk driving control and drug control in the police field, and firefighting field. It is used in a wide range of fields such as fire cause investigation and health care in the health industry field.

[0003] This breath analyzer uses gas chromatography. The breath analyzer is attached to the main body of the breath analyzer and has an outer peripheral portion covered with a heater. Two carrier gas flow paths each connected via a four-way electromagnetic valve, an air cylinder connected to the four-way electromagnetic valve, and a sample measuring section provided by partitioning a part of each carrier gas flow path; It has.

[0004] On the downstream side of each sample measuring section, a breathing introduction pump (suction pump) connected via a three-way electromagnetic valve and an exhaust pipe is provided. In addition, each of the three-way solenoid valves is provided with two separation columns and the like connected in parallel and independently of each other.

[0005] In the case of collecting and analyzing exhaled breath from a subject, when the subject exhales into the exhalation collection tube, the exhaled breath is discharged into the exhalation collection tube by the exhalation introduction pump. While being discharged to the outside of the device, a part of the breath is filled in each sample measuring section as a breath sample. Next, when the carrier gas is sent from the air cylinder to each sample measuring section, after the breath sample filled in each measuring section is sent to each separation column, each breath sample is separated by a difference in the retention time of each component gas. Separated. Thereafter, the breath analysis is performed by a predetermined calculation process.

[0006]

[Problems to be Solved by the Invention] Toxemia of pregnancy, diabetes,
In arteriosclerosis and the like, the concentration of pentane in the breath increases due to lipid peroxidation, and the concentration is at most on the order of pg / mL.
However, the conventional breath analyzer has a disadvantage that it cannot analyze low-concentration components of pg / mL order such as pentane because the limit of the components that can be analyzed is at least ng / mL.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an apparatus and method for analyzing pentane in exhaled breath, which can solve the disadvantages of the prior art and can analyze pentane which is slightly contained in exhaled breath. is there.

[0008]

SUMMARY OF THE INVENTION An analyzer according to the present invention has a capillary having a coating layer made of an inert porous polymer on an inner wall surface and passing a breath sample to separate pentane contained in the breath sample. A column, a collection tube in which the breath sample is adsorbed, a concentrated sample introduction section for desorbing the breath sample adsorbed in the collection tube, and a carrier for the breath sample desorbed in the concentrated sample introduction section. The apparatus includes a carrier gas control unit that allows gas to pass through the capillary column, and a detector that detects pentane separated by the capillary column.
The analysis method according to the present invention is a method using the analyzer according to the present invention, and optimizes analysis conditions such as the length of the capillary column, the temperature of the capillary column, and the flow rate of the carrier gas.

The breath sample concentrated and collected in the collection tube is desorbed at the concentrated sample introduction part, and passes through the capillary column together with the carrier gas. The concentration of the breath sample with respect to the carrier gas is much higher than when the non-concentrated breath sample is flowed together with the carrier gas.
That is, the detector can obtain a detection value with a high peak.
Therefore, even low-concentration components that are slightly contained in the breath can be sufficiently analyzed.

However, other than pentane, other components close to the retention time of pentane are mixed in such a component. Therefore, the present inventor repeated experiments on various types of separation columns in order to separate pentane from these components, and as a result, it was found that a "capillary having a coating layer made of an inert porous polymer on the inner wall surface. Column "is the best. As an inert porous polymer, for example, divinylbenzene ethylene glycol dimethacrylate (Divinylbenzenethyleneg
lycoldimethacrylate). In addition to this
The present inventors have found that the retention times of pentane and dimethyl sulfide are reversed depending on the analysis conditions. That is, pentane and dimethyl sulfide cannot be separated due to the overlapping of the retention times depending on the analysis conditions, but can be completely separated by optimizing the analysis conditions.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 and 2 are configuration diagrams showing an embodiment of an analyzer according to the present invention. FIG. 1 shows a state in which a first carrier gas flow path is switched, and FIG. This shows a state in which the flow has been switched to the second carrier gas flow path. Hereinafter, description will be made mainly with reference to these drawings.

An analyzer 10 according to the present invention includes a capillary column 12 having a coating layer made of an inert porous polymer on an inner wall surface and passing a breath sample A to separate pentane contained in the breath sample A; A collection tube 14 in which the breath sample A is adsorbed, and a concentrated sample introduction unit 16 for desorbing the breath sample A adsorbed in the collection tube 14
A carrier gas control unit 18 that allows the breath sample A desorbed in the concentrated sample introduction unit 16 to pass through the capillary column 12 with the carrier gas C, and a detector 20 that detects pentane separated by the capillary column 12. I have.

The capillary column 12 is made of, for example, a fused silica material having an inner diameter of 0.3 to 1.0 [mm] and a length of approximately
10 to 25 [m], the thickness of the coating layer is 10 to 20 [μ
m], the material of the coating layer is divinylbenzene ethylene glycol dimethacrylate. Generally, the longer the capillary column 12 is, the longer the time required for analysis becomes, while the longer the length of the capillary column 12 becomes, the better the resolution becomes.
[M] is appropriate. On the carrier gas introduction side of the capillary column 12, a pre-column 121 is provided.
The pre-column 121 is for removing unnecessary components and has a property of easily retaining a high-boiling component such as hexane, for example, but is not always necessary.

The concentrated sample introducing section 16 includes a collecting tube support 161 for supporting the collecting tube 14, a secondary concentrating tube 162 for adsorbing the breath sample A therein, and a secondary concentrating tube 162 for supporting the secondary concentrating tube 162. And a concentration tube support 163. The collecting tube support 161 has a built-in first heating means (not shown) for desorbing the breath sample A adsorbed in the collecting tube 14. The secondary concentrating tube support 163 has a cooling means (not shown) for adsorbing the breath sample A from which the collection tube 14 has been desorbed to the inside of the secondary concentrating tube 162, and heating the secondary concentrating tube 162 for secondary A second heating means (not shown) for desorbing the breath sample A adsorbed in the concentration tube 162 is incorporated therein.
For example, the first and second heating means are electric heaters, and the cooling means is a container containing liquid nitrogen.

As the secondary concentrating tube 162, a capillary tube having an inner diameter of 0.5 to 1.0 mm is used, and it is preferable that the material and the characteristics are the same as those of the capillary column 12. In addition, secondary concentrator tube 1
Since the liquid 62 is coated with the liquid phase of the adsorbent, the efficiency of the secondary concentration is higher than that of the uncoated tube. When the concentration ratio of the collection tube 14 is high, the secondary concentration tube 162 and the secondary concentration tube support 163 may be omitted.

The carrier gas control section 18 purges the capillary column 12 and the like with the first carrier gas flow path 181 (FIG. 1) through which the breath sample A passes through the capillary column 12 with the carrier gas C. A second carrier gas flow path 182 (FIG. 2) and a sampling valve 183 that can be switched to one of the carrier gas flow paths 181 and 182 are provided. The carrier gas flow path 181 allows the breath sample A to pass through the pre-column 121 and then passes through the capillary column 12, and the carrier gas flow path 182 separately purges the pre-column 121 and the capillary column 12.

The sampling valve 183 is, for example, a rotary valve having eight ports 1 to 8. FIG.
Is a schematic sectional view showing an example of a sampling valve 183. In FIG. 3, the sampling valve 183 is
Fixed body 183A having ports 1 to 8 and communication pipes a to d
And an actuator (not shown) such as a solenoid for rotating the rotating body 183B. FIG. 3A shows a state in which the carrier gas channel 181 has been switched, and FIG. 3B shows a state in which the carrier gas channel 182 has been switched.

A gas cylinder 221 filled with a carrier gas C is provided in the carrier gas control section 18 by a pressure reducing valve 222.
And a manual valve 223. As the carrier gas C, air, hydrogen, nitrogen, helium, argon or the like is generally used. The port 1 is connected to a pipe 241 for introducing the carrier gas C that has passed through the concentrated sample introduction unit 16 via a filter 164. The port 2 is connected to a pipe 242 for discharging the carrier gas C that has passed through the concentrated sample introduction unit 16. The port 3 is provided with a pipe 24 for introducing the carrier gas C through an electromagnetic valve 184.
3 are connected. Port 4 has a pre-column 121
Is connected to a pipe 244 connected to one end of the pipe. The port 5 is connected to a pipe 245 connected to one end of the capillary column 12. The port 6 is connected to a pipe 246 for introducing the carrier gas C via an electromagnetic valve 185. The port 7 is connected to a pipe 247 for discharging the carrier gas C. The port 8 is connected to a pipe 248 connected to the other end of the precolumn 121. Further, the carrier gas control unit 18 is provided with control means 186 for controlling the energization of the sampling valve 183 and the solenoids of the solenoid valves 184 and 185.
The control means 186 may be of any type including a manual switch, a relay and a timer, a microcomputer and its program, and the like. In addition, the pre-column 121, the capillary column 12,
Sampling valves 183 and piping 24 around them
Are housed in a thermostat (not shown) kept at a constant temperature of, for example, 100 ° C. Capillary column 12 described later
Is set by this thermostat.

As the detector 20, a detector for detecting mass, heat conduction, and the like can be used.

Next, the operation of the analyzer 10 will be described.

First, the breath sample A is adsorbed on the collection tube 14 using the breath concentration / collection device 80 shown in FIG. The exhaled breath collection device 80 includes a Tedlar bag 82 filled with the exhaled air A ′, a collection tube 14 communicating with the Tedlar bag 82, and an exhaled air A ′ in the Tedlar bag 82.
A pump 84 for suctioning the air through the collecting tube 14, an integrating flow meter 86 for measuring the integrated flow rate f of the exhalation A 'passing through the collection tube 14, a pressure gauge 88 for measuring the pressure p of the exhalation A' in the Tedlar bag 82, and a pressure gauge a main control unit 90 that the pressure p of the measured expiratory a 'stops the pump 84 when it becomes less than a predetermined value p _F 88, an incubator 92 for a constant temperature T of the collecting tube 14, capturing A water absorption filter 94 is provided in the flow path of the exhalation A ′ between the collecting pipe 14 and the pump 84. Tedlar bag 82, T-tube 881 of pressure gauge 88,
The collection tube 14, the water absorption filter 94, the pump 84, and the integrating flow meter 86 are connected by flexible tubes 95a to 95e, respectively.

The collection tube 14 is filled with an adsorbent 141 for adsorbing the breath sample A. Tedlar bag 82
Has an exhalation discharge port 821 and an exhalation blowout port 822. Although not shown, the exhalation discharge port 821 and the exhalation blow port 822 are provided with stop valves that can be manually opened and closed. In advance, the subject attaches the disposable mouthpiece 823 to the breath inlet 822 and
3 and the exhalation A ′ is blown into the Tedlar bag 82. The integrating flow meter 86 is a general gas flow meter such as a mass flow meter. The pressure gauge 88 uses, for example, a piezoelectric effect that generates a voltage when a pressure is applied to a piezoelectric element, and outputs an electric signal corresponding to the pressure p of the exhalation A ′ to the main control unit 90. The main control unit 90 includes, for example, a microcomputer including a CPU, a ROM, a RAM, an input / output interface, and the like, and a computer program stored in the ROM or the like. The operation of the main control unit 90, drives the pump 84 with stops when the pressure p of exhalation A 'output from the pressure gauge 88 becomes equal to or less than a predetermined value p _F, buzzer for informing not shown, the lamp It is programmed to be. According to experiments, the pressure p during suction is, for example, -0.05 kgf / cm ² ,
The pressure p at the end of suction (that is, the constant value p _F ) is, for example, −0.3 to −0.4 kgf / cm ² . The thermostat 92 includes a heating / cooling unit 96 and a temperature control unit 97. The heating and cooling unit 96 can be divided into an upper side 98 and a lower side 99, and the upper side 98 and the lower side 99 sandwich the collection tube 14. Therefore, the collection tube 14 is connected to the heating / cooling unit 96.
Can be easily attached and detached. The upper side 98 is composed of a heat insulating material 981, a heat transfer material 982, and the like. The lower side 99 is a heat insulating material 9
91, a heat transfer material 992, a Peltier element 993, a radiation fin 994, and the like. The heat transfer members 982, 992 and the radiation fins 994 are made of aluminum. A thermocouple 971 is embedded inside the heat transfer material 992. The thermocouple 971 outputs a voltage corresponding to the temperature T of the heat transfer material 992, that is, the temperature of the collection tube 14, to the temperature control unit 97. The temperature control unit 97 includes, for example, a microcomputer including a CPU, a ROM, a RAM, an input / output interface, and the like.
It is composed of a computer program for temperature control stored in the OM or the like, and a DC voltage power supply. Operation of the temperature control unit 97, as the temperature T of the collecting tube 14, which is outputted from the thermocouple 971 is a constant value T _C, in which the Peltier element 993 for controlling energization. When the fixed value T _C is equal to or higher than room temperature, a simple electric heater or the like may be used instead of the Peltier element 993. Inside the moisture absorption filter 94, a hygroscopic material 941 such as silica gel, calcium carbonate or the like is provided.
Is filled.

When the pump 84 operates, the exhalation A ′ is sucked from the Tedlar bag 82 through the collection tube 14. Thereby, the exhalation component A is concentrated and collected by the adsorbent 141 of the collection tube 14. At this time, the pressure p during suction is measured by the pressure gauge 88, and the integrated flow rate f is measured by the integrated flow meter 86. If Tedlar bag 82 is emptied, the pressure p reaches a predetermined value p _F, the main control unit 90 is a pump 8
4 is stopped. The integrated flow rate f at the end of the suction is output from the integrated flow meter 86 to the main control unit 90.
The amount of expiration A 'concentrated in the water is also known.

Subsequently, the collection tube 14 is connected to the concentrated sample introduction section 16.
, The collection tube 14 is heated to, for example, 250 ° C., and the secondary concentration tube 162 is cooled to, for example, −130 to −180 ° C.,
At the same time, the carrier gas flow path 181 (FIG. 1) is selected, and the carrier gas C is passed from the collection pipe 14 to the secondary concentration pipe 162. Then, the breath sample A desorbs the collection tube 14 and
It is further concentrated and adsorbed on the secondary concentration tube 162.

When the adsorption of the breath sample A to the secondary concentration tube 162 is completed, the secondary concentration tube 162 is heated to, for example, 190.degree. At this time, to save the carrier gas C, the solenoid valve 18 is used.
Since 4,185 is closed, the carrier gas C is
Concentrated sample introduction section 16 → filter 164 → port 1 → port 8 → pre-column 121 → port 4 → port 5 → capillary column 12 → detector 20 → discharge. The breath sample A also flows with the carrier gas C, and the pre-column 121,
It passes through the capillary column 12 and the detector 20. Each component contained in the breath sample A is detected by the detector 20 with a time difference by being separated by the precolumn 121 and the capillary column 12. The detector 20 performs qualitative analysis based on the volume (retention capacity) or the time (retention time) of the carrier gas C from the time when the breath sample A is injected until the separation zone of each component appears, and the peak area or peak height is determined. Thus, a quantitative analysis is performed.

According to the analyzer 10, the concentrated sample introduction unit 1
Since the breath sample A concentrated by Step 6 is used, even low-concentration components such as pentane containing only pg / mL in the breath can be sufficiently analyzed.

In the analyzer 10, for example, when pentane is detected in about 6 minutes, hexane is detected in about 30 minutes.
Therefore, when only pentane is analyzed, the analysis after detecting pentane is unnecessary. When the analysis of the desired component is completed, the control means 186 switches the carrier gas flow path 181 (FIG. 1) to the carrier gas flow path 182 (FIG. 2).
Switch to. At this time, since the solenoid valves 184 and 185 are opened, the carrier gas C is supplied to the concentrated sample introduction unit 16 →
Filter 164 → port 1 → port 2 → discharge, solenoid valve 184 → port 3 → port 4 → pre-column 121 → port 8 → port 7 → discharge, solenoid valve 185 → port 6 → port 5 → capillary column 12 → detector 20 → Discharges, and flows in three directions. Thereby, the concentrated sample introduction unit 1
6. The pre-column 121, the capillary column 12, the detector 20, etc. are purged.

At this time, since the pre-column 121 and the capillary column 12 are separately purged, the purge is completed in a shorter time as compared with the method of purging while keeping the pre-column 121 and the capillary column 12 connected.
Therefore, there is an effect that the analysis time can be reduced.

The above embodiment is, of course, merely an example and does not limit the present invention. For example,
The sampling valve 183 may switch the flow path by switching an electromagnetic valve. Concentrated sample introduction unit 1
The function of controlling the detector 6 and the detector 20 may be provided to the control unit 186 so that the analyzer 10 can be fully automated.

FIG. 5 is a chromatogram for explaining the definition of the degree of separation R. Here, for the components A and B to be eluted, the retention time is trA and trB, and the width of the peak is W.
A and WB. Then, the degree of separation R is R = 2 (trB
−trA) / (WA + WB). At R = 1, a 2% overlap occurs at the base. At R = 1.5, almost complete separation is possible. At R = 2, separation is possible even if there is another peak between peak A and peak B.

FIG. 6 shows the degree of separation R ₁₂ ,
It is a chromatogram for explaining the R _23, R _34. In the figure, E indicates ethanol, D indicates dimethyl sulfide, P indicates pentane, and I indicates the peak of isoprene (the same applies to the following chromatograms). The retention times of pentane and dimethyl sulfide are reversed depending on the conditions. FIG. 6A shows the case where the retention time of pentane is longer than that of dimethyl sulfide.
[B] is a case where the retention time of pentane is shorter than that of dimethyl sulfide. As is clear from FIG. 6, R ₁₂ represents the degree of separation between ethanol and dimethyl sulfide or pentane, and R ₂₃
Indicates the degree of separation between dimethyl sulfide and pentane, and R ₃₄ indicates the degree of separation between dimethyl sulfide or pentane and isoprene. Thus, the reversal of the retention time of the dimethyl sulfide and pentane, there is no effect on the calculation of the separation R _23.

Next, a capillary column 1 having a length of 10 [m]
The results of optimizing the analysis conditions such as the temperature of the capillary column and the flow rate of the carrier gas in the case of using No. 2 will be described. FIG. 7 shows that the flow rate of the carrier gas is 5 ml
/ Min.] Is a graph showing the retention time of each component with respect to the temperature of the capillary column when constant. FIG.
Is a graph showing the retention time of each component with respect to the flow rate of the carrier gas when the temperature of the capillary column is kept constant at 110 [° C.]. FIG. 9 shows the temperature of the capillary column.
13 is a graph showing the retention time of each component with respect to the flow rate of the carrier gas when 130 [° C.] is constant. FIG.
5 is a graph showing the degree of separation of each component with respect to the temperature of the capillary column when the flow rate of the carrier gas is fixed at 5 [ml / min.]. FIG. 11 is a graph showing the degree of separation of each component with respect to the flow rate of the carrier gas when the temperature of the capillary column is kept constant at 110 ° C. FIG.
5 is a graph showing the degree of separation of each component with respect to the flow rate of a carrier gas when the temperature of a capillary column is constant at 130 ° C. FIG. 13 shows that the flow rate of the carrier gas is 5 ml
/ Min.] Is a graph showing the relative retention time of each component with respect to the temperature of the capillary column when it is constant. Here, the relative retention time refers to the retention time of each component when the retention time of ethanol is "1". FIG. 14 is a chromatogram when the flow rate of the carrier gas is constant at 5 [ml / min.] And the temperature of the capillary column is constant at 90 [° C.]. FIG. 15 is a chromatogram when the flow rate of the carrier gas is constant at 5 [ml / min.] And the temperature of the capillary column is constant at 110 [° C.]. FIG. 16 is a chromatogram when the flow rate of the carrier gas is constant at 5 [ml / min.] And the temperature of the capillary column is constant at 130 [° C.]. FIG. 17 is a chromatogram when the flow rate of the carrier gas is constant at 5 [ml / min.] And the temperature of the capillary column is constant at 150 [° C.].

As shown in FIG. 10, the temperature of the capillary column is preferably 125 to 135 ° C., more preferably 130 ° C. In this temperature range, as shown in FIG. 13, the retention time of dimethyl sulfide is longer than that of pentane, so that the chromatogram of FIG. 6B is obtained. Therefore, R ₁₂ is the degree of separation between ethanol and pentane,
₂₃ is the degree of separation between pentane and dimethyl sulfide. The lower limit is set to 125 ° C.
As shown in, but R ₁₂ is not less than 1.5, R ₂₃ is 1.3
This is because: The upper limit was set to 135 [° C.] above 135 [° C.], as shown in FIG.
Although R ₂₃ is more than 1.5, because R ₁₂ becomes 1.3 or less.

As shown in FIG. 12, the flow rate of the carrier gas is preferably 3 to 6 [ml / min.], And more preferably 5 [ml / min.]. Under the temperature condition of 130 ° C. in FIG.
Since the retention time of dimethyl sulfide is longer than that of pentane as shown in FIG. 3, the chromatogram of FIG. 6B is obtained. Thus, R ₁₂ is the separation between ethanol and pentane, and R ₂₃ is the separation between pentane and dimethyl sulfide. The lower limit was set to 3 [ml / min.] Because 3 [ml / min.
min.] In the following, as shown in FIG. 12, because R ₁₂ is 1.5 or less and R ₂₃ becomes 1.4 or less. The upper limit was set to 6 [ml / min.], In the 6 [ml / min.] Or more, as shown in FIG. 12, although R ₁₂ is not less than 1.5,
R ₂₃ is because becomes 1.4 or less.

Next, a capillary column 1 having a length of 25 [m]
The results of optimizing the analysis conditions such as the temperature of the capillary column and the flow rate of the carrier gas in the case of using No. 2 will be described. FIG. 18 shows that the flow rate of the carrier gas is 5
6 is a graph showing the retention time of each component with respect to the temperature of the capillary column when [ml / min.] Is fixed. FIG. 19 is a graph showing the retention time of each component with respect to the flow rate of the carrier gas when the temperature of the capillary column is constant at 100 [° C.]. FIG. 20 is a graph showing the retention time of each component with respect to the flow rate of the carrier gas when the temperature of the capillary column is kept constant at 110 ° C. FIG.
1 is a graph showing the degree of separation of each component with respect to the temperature of the capillary column when the flow rate of the carrier gas is fixed at 5 [ml / min.]. FIG. 22 is a graph showing the degree of separation of each component with respect to the flow rate of the carrier gas when the temperature of the capillary column is kept constant at 100 [° C.]. FIG.
3 is a graph showing the degree of separation of each component with respect to the flow rate of the carrier gas when the temperature of the capillary column is kept constant at 110 [° C.]. FIG. 24 shows that the flow rate of the carrier gas is 5
6 is a graph showing the relative retention time of each component with respect to the temperature of the capillary column when [ml / min.] Is fixed. Here, the relative retention time refers to the retention time of each component when the retention time of ethanol is "1".

As shown in FIG. 21, the temperature of the capillary column is preferably 85 to 115 ° C., more preferably 90 to 110 ° C. In this temperature range, as shown in FIG. 24, since the retention time of pentane is longer than that of dimethyl sulfide, the chromatogram of FIG. 6A is obtained. Thus, R ₂₃ is the separation between dimethyl sulfide and pentane;
R ₃₄ is the separation degree between pentane and isoprene. The reason why the lower limit is set to 85 ° C. is that, when the temperature is 85 ° C. or less, as shown in FIG. 21, although R ₂₃ is 2.0 or more, R ₃₄ tends to be 1.5 or less. 115 upper limit
The reason why the temperature is set to [° C.] is that when the temperature is higher than 115 [° C.], as shown in FIG. 21, although R ₃₄ is 2.4 or more, R ₂₃ is 1.6 or less.

It is preferable that the flow rate of the carrier gas is made different depending on the temperature of the capillary column in the range of 85 to 105 ° C. and the range of 105 to 115 ° C. When the temperature of the capillary column is 85 to 105 [° C.], as shown in FIG. 22, the flow rate of the carrier gas is preferably 2 to 25 [ml / min.], And more preferably 5 to 20 [ml / min.]. Under the temperature condition of 100 [° C.] in FIG. 22, the retention time of pentane is longer than that of dimethyl sulfide as shown in FIG. 24, so that the chromatogram of FIG. 6A is obtained. Thus, R ₂₃ is the separation between dimethyl sulfide and pentane, and R ₃₄ is the separation between pentane and isoprene. The lower limit is 2 [ml /
min.] is because if it is 2 [ml / min.] or less, sufficient signal intensity cannot be obtained. The upper limit is 25 [ml /
The reason for this is that R ₂₃ and R ₃₄ decrease as shown in FIG. 22 at 25 [ml / min.] or more. When the temperature of the capillary column is 105 to 115 [° C.], the flow rate of the carrier gas is 2 to 10 [ml / mi.
n.] is preferable, and 5 [ml / min.] is more preferable. FIG.
3 temperature condition 110 nor [℃], as shown in FIG. 24 R ₂₃
Is the degree of separation between dimethyl sulfide and pentane, R ₃₄ is the separation degree between pentane and isoprene. Lower limit 2 [ml
/ Min.] Is because if it is 2 [ml / min.] Or less, sufficient signal intensity cannot be obtained. The upper limit is 10 ml
/ Min.] In FIG. 23 for 10 [ml / min.] Or more.
As shown in, but R ₃₄ is 2.0 or more, R ₂₃ is 1.4
This is because:

The results of optimizing the analysis conditions when using the capillary column 12 having a length of 10 [m] and a length of 25 [m] have been described above. The capillary column 1 based on the difference in length of these capillary columns 12
Taking into account the difference in the separation performance of 2, the capillary column 12 having a length of 8 to 12 [m] can obtain substantially the same results as the capillary column 12 having a length of 10 [m] under the above-described analysis conditions. Capillary column 12 with a length of 20-30 [m]
It is considered that the same result as that of the capillary column 12 having a length of 25 [m] can be obtained by the above-described analysis conditions.

[0039]

According to the analyzer of the present invention, a capillary column having a coating layer made of an inert porous polymer on the inner wall surface is used, and a breath sample concentrated and collected in a collection tube is concentrated. Desorb at the sample introduction part,
Since the breath sample is passed through the capillary column by the carrier gas, pentane which is only slightly contained in the breath can be sufficiently analyzed.

According to the analysis method of the second to fourth aspects,
By optimizing the analysis conditions such as the length of the capillary column, the temperature of the capillary column, the flow rate of the carrier gas, etc., the detection accuracy of pentane can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of an analyzer according to the present invention, showing a state in which the analyzer is switched to a first carrier gas flow path.

FIG. 2 is a configuration diagram showing one embodiment of the analyzer according to the present invention, and shows a state in which the analyzer is switched to a second carrier gas flow path.

FIG. 3 is a schematic cross-sectional view showing an example of a sampling valve in the analyzer of FIGS. 1 and 2; FIG.
[2] shows a state in which the flow is switched to the second carrier gas flow path.

FIG. 4 is a cross-sectional configuration diagram illustrating an example of a breath concentration and collection device.

FIG. 5 is a chromatogram for explaining the definition of the degree of separation R.

FIG. 6 is a chromatogram for explaining the degrees of separation R ₁₂ , R ₂₃ , and R ₃₄ used in FIGS. 10 to 12 and FIGS. 21 to 23. FIG. 6A shows the case where the retention time of pentane is longer than that of dimethyl sulfide, and FIG. 6B shows the case where the retention time of pentane is shorter than that of dimethyl sulfide.

FIG. 7 shows a flow rate of carrier gas of 5 [ml / mi] in a capillary column having a length of 10 [m] according to an embodiment of the present invention.
n.] A graph showing the retention time of each component with respect to the temperature of the capillary column when it is constant.

FIG. 8 shows the temperature of the capillary column in a 10 [m] long capillary column according to one embodiment of the present invention.
4 is a graph showing the retention time of each component with respect to the flow rate of a carrier gas when [° C.] is constant.

FIG. 9 shows the temperature of a capillary column having a length of 130 m in a capillary column according to an embodiment of the present invention.
4 is a graph showing the retention time of each component with respect to the flow rate of a carrier gas when [° C.] is constant.

FIG. 10 shows a flow rate of carrier gas of 5 [ml / mi] in a capillary column having a length of 10 [m] according to an embodiment of the present invention.
n.] A graph showing the degree of separation of each component with respect to the temperature of the capillary column when it is constant.

FIG. 11 shows a capillary column having a length of 10 [m] of one embodiment of the present invention.
5 is a graph showing the degree of separation of each component with respect to the flow rate of a carrier gas when [° C.] is constant.

FIG. 12 shows the temperature of a capillary column having a length of 130 m in a capillary column having a length of 130 m according to an embodiment of the present invention.
5 is a graph showing the degree of separation of each component with respect to the flow rate of a carrier gas when [° C.] is constant.

FIG. 13 shows a flow rate of carrier gas of 5 [ml / mi] in a capillary column having a length of 10 [m] according to an embodiment of the present invention.
n.] A graph showing the relative retention time of each component with respect to the temperature of the capillary column when constant.

FIG. 14 shows a flow rate of a carrier gas of 5 [ml / mi] in a capillary column having a length of 10 [m] according to an embodiment of the present invention.
n.] It is a chromatogram when the temperature is constant and the capillary column temperature is constant at 90 ° C.

FIG. 15 shows a flow rate of carrier gas of 5 [ml / mi] in a capillary column having a length of 10 [m] according to an embodiment of the present invention.
n.] It is a chromatogram when constant and the temperature of the capillary column is constant at 110 [° C.].

FIG. 16 shows a flow rate of a carrier gas of 5 [ml / mi] in a capillary column having a length of 10 [m] according to an embodiment of the present invention.
n.] It is a chromatogram in the case where the temperature is constant and the temperature of the capillary column is 130 [° C.].

FIG. 17 shows a flow rate of carrier gas of 5 [ml / mi] in a capillary column having a length of 10 [m] according to an embodiment of the present invention.
n.] It is a chromatogram when constant and the temperature of the capillary column is fixed at 150 [° C.].

FIG. 18 shows a flow rate of carrier gas of 5 [ml / mi] in a capillary column having a length of 25 [m] according to an embodiment of the present invention.
n.] A graph showing the retention time of each component with respect to the temperature of the capillary column when it is constant.

FIG. 19 shows a capillary column having a length of 25 [m] according to an embodiment of the present invention.
4 is a graph showing the retention time of each component with respect to the flow rate of a carrier gas when [° C.] is constant.

FIG. 20 shows a capillary column having a length of 25 [m] in one embodiment of the present invention, in which the temperature of the capillary column is set to 110
4 is a graph showing the retention time of each component with respect to the flow rate of a carrier gas when [° C.] is constant.

FIG. 21 shows a flow rate of a carrier gas of 5 [ml / mi] in a capillary column having a length of 25 [m] according to an embodiment of the present invention.
n.] A graph showing the degree of separation of each component with respect to the temperature of the capillary column when it is constant.

FIG. 22 shows a capillary column having a length of 25 [m] according to an embodiment of the present invention.
5 is a graph showing the degree of separation of each component with respect to the flow rate of a carrier gas when [° C.] is constant.

FIG. 23 shows a capillary column having a length of 25 [m] in one embodiment of the present invention, in which the temperature of the capillary column is set to 110;
5 is a graph showing the degree of separation of each component with respect to the flow rate of a carrier gas when [° C.] is constant.

FIG. 24 shows a flow rate of carrier gas of 5 [ml / mi] in a capillary column having a length of 25 [m] according to an embodiment of the present invention.
n.] A graph showing the relative retention time of each component with respect to the temperature of the capillary column when it is constant.

[Description of Signs] 10 Analyzer 12 Capillary column 14 Collection tube 16 Concentrated sample introduction unit 18 Carrier gas control unit 20 Detector A Breath sample C Carrier gas

Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location G01N 30/60 G01N 30/60 K

Claims (4)

[Claims] 1. A capillary column having a coating layer made of an inert porous polymer on an inner wall surface and passing a breath sample to separate pentane contained in the breath sample, and a trapping device in which the breath sample is adsorbed. A collection tube, a concentrated sample introduction unit for desorbing the breath sample adsorbed in the collection tube, and a carrier gas control unit for passing the breath sample desorbed in the concentrated sample introduction unit through the capillary column with a carrier gas. And a detector for detecting pentane separated by the capillary column. 2. The apparatus for analyzing pentane in exhaled breath according to claim 1, wherein the capillary column having a length of 8 to 12 [m] is used.
135 ° C., and the flow rate of the carrier gas is 3 to 6 [ml
/ Min.], The method for analyzing pentane in breath. 3. The apparatus for analyzing pentane in exhaled breath according to claim 1, wherein when the capillary column having a length of 20 to 30 [m] is used, the temperature of the capillary column is 85 to 10 [m].
5 ° C., and the flow rate of the carrier gas is 2 to 30 [ml /
min.], the method for analyzing pentane in breath. 4. The apparatus for analyzing pentane in exhaled breath according to claim 1, wherein the capillary column having a length of 20 to 30 [m] is used.
115 ° C., the flow rate of the carrier gas is 2 to 10
/ Min.], The method for analyzing pentane in breath.