JPH0538561U - Gas chromatograph detector - Google Patents

Abstract

(57) [Summary] [Objective] By integrating a thermal ionization detector selectively sensitive to organic nitrogen compounds and a surface ionization detector selectively sensitive to amine compounds,
It is possible to simultaneously measure a compound having a strong adsorptivity such as an amine compound, and improve the accuracy of quantitative measurement in a gas chromatograph. The effluent from the column of the gas chromatograph apparatus is first introduced into the surface ionization detector 1b, where a compound having a low ionization potential such as an amine compound is ionized, and this ion current is measured. Then, it is sent to the thermal ionization detector 1a and the organic nitrogen compound is measured.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a detector for a gas chromatograph.

[0002]

[Prior Art]

 Conventionally, as a detector for a gas chromatograph, a hydrogen flame ionization detector (FID), a thermal ionization detector (FTD), an electron capture detector (ECD), a constant current electron capture detector, a clean constant current electron capture detector ( C-ECD), thermal conductivity detector (TCD), flame photometric detector (FPD), surface ionization detector (SID), etc. It is used.

[0003]

[Problems to be solved by the device]

 However, the conventional gas chromatograph detector has the following problems.

(1) When signals from different types of detectors are obtained at the same time, the measurement components must be branched at the outlet of the column and a sample must be sent to each detector. There is a problem in that the sample amount decreases and the measurement sensitivity decreases. There was also a problem that the accuracy of quantification would decrease unless the proportion of the sample amount sent to each detector was adjusted accurately.

(2) Further, in order to solve the problem described in (1) above, it is assumed that the detectors are connected in series. However, a gas chromatograph measuring device is equipped with a plurality of detectors. There has been a problem that it is difficult to downsize the measuring device because a pace is required.

(3) When the detectors are connected in series, the pipe connecting the detectors is indispensable, and a compound having a strong adsorptive property such as an amine compound is introduced as a sample. Then, there was a problem that it could not be accurately measured because it was adsorbed inside the connected pipes.

In order to solve the above problems, the present invention provides a detector for a gas chromatograph capable of measuring a sample containing an organic nitrogen compound and an amine compound and simultaneously outputting data on each compound. With the goal.

[0008]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the gas chromatograph detector of the present invention comprises a thermal ionization detector which is selectively sensitive to organic nitrogen compounds and a surface ionization detector which is selectively sensitive to amine compounds. It is characterized by integrating.

[0009]

[Action]

 According to the above configuration, since the thermal ionization detector and the surface ionization detector are integrated, the flow rates of the gas, carrier gas, hydrogen, and air used are almost the same in each detector. Are the same, and the accuracy of quantitative measurement of each detector is improved.

Further, since the information obtained from the thermal ionization detector and the information obtained from the surface ionization detector can be obtained at the same time, various components such as environmental analysis and analysis of extracts from biological samples can be measured. In doing so, component analysis such as qualitative analysis and quantitative analysis becomes easy.

[0011]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional view of a gas chromatograph detector of the present invention. The gas chromatograph detector 1 is composed of a thermal ionization detector 1a and a surface ionization detector 1b, and a column connection port 2 is provided in the surface ionization detector 1b. The thermal ionization detector 1a is also called an alkaline flame detector (AFID), and uses a salt of an alkali metal such as sodium, potassium, cesium, or rubidium as an alkali source 18 for heating by a hydrogen flame formed in the quartz nozzle 13. , Metal salt vapor is generated by heating an electric heater connected between the inner collector 22 and the outer collector 19.

A power controller 23 is connected to the inner collector 22 and the outer collector 19 via a transformer 31, and controls the current flowing to the electric heater. The ring electrode 14 provided at the tip of the quartz nozzle 13 is connected to a DC power source 15 and a positive voltage of about 200 V to 300 V is applied to the ground potential of the gas chromatograph device. An electrometer 24 for detecting a minute current is connected to the inner collector 22, and the thermionic current flowing between the ring electrode 14 and the inner collector 22 is measured. The air supply port 16 is preferably supplied with air at a flow rate of 30 to 50 ml / min, and the hydrogen supply port 17 is preferably supplied with hydrogen at a flow rate of 3 to 7 ml / min. Such a thermal ionization detector 1a is selectively sensitive to nitrogen compounds and phosphide compounds.

Next, the surface ionization detector 1b will be described. A platinum emitter 5 wound in a coil shape is connected between the inner collector 6 and the outer collector 7, a current is supplied from the power controller 10 via the transformer 30, and the temperature is controlled to 800K to 1200K. On the surface of the heated platinum emitter 5, the organic compound is decomposed into radicals and ionized.

The ring electrode 4 provided at the tip of the quartz nozzle 13 is connected to a DC power source 9, and a negative voltage of about −200 V is applied to the ground potential of the gas chromatograph device. An electrometer 11 for detecting a minute current is connected to the inner collector 6 to measure an ion current flowing between the ring electrode 4 and the inner collector 6. The air supply port 8 is preferably supplied with air at a flow rate of 20 to 50 ml / min. Such a surface ionization detector 1b is selectively sensitive to a tertiary amine and a secondary amine.

The effluent from the column of the gas chromatograph device is first introduced into the surface ionization detector 1b, and is moved by a carrier gas such as helium onto the heated platinum surface under an atmosphere of air. Ionize compounds with low ionization potential, such as amine compounds, and measure the ion current. Then, it is sent to the thermal ionization detector 1a, where the organic nitrogen compound is measured. With these two measurement results, it is possible to immediately determine which peak corresponds to the amine compound in the graph measured by the thermal ionization detector.

FIG. 2 shows an example of data measured using the gas chromatograph detector of the present invention. FIG. 2a is output data from the surface ionization detector, and FIG. 2b is a thermal ionization detector. Is the output data of. A sample with a sample volume of 4 μl containing haloperidol with a concentration of 100 ng / ml and bromperidol with a concentration of 500 ng / ml was injected into a gas chromatograph measuring device (trade name: GC-15APFSi, manufactured by Shimadzu Corporation) to use as a carrier gas. Helium is flown at a flow rate of 3.4 ml / min, surface ionization detector 1b is flown at a flow rate of 50 ml / min, and thermal ionization detector 1a is at a flow rate of 40 ml / min and 4 ml / min. The measurement was performed by flowing hydrogen gas at a flow rate. The column used was a fused silica capillary column DB-1 (dimethylpolysiloxane, non-polar, 0.31 mm (inner diameter), 30 m (length), film thickness 1 μm) (trade name: GC-1 5APFSi, Shimadzu Corporation). Manufactured) to a temperature of 300 ° C.

As a result of the measurement, the peak α of haloperidol and the peak β of bromperidol were detected with higher sensitivity in the surface ionization detector of FIG. 2a than in the thermal ionization detector of FIG. 2b. It can be seen that other organic nitrogen compounds are detected with higher sensitivity in the thermal ionization detector of FIG. 2b. Furthermore, since both data are output at the same time, mutual qualitative and quantitative component analysis could be performed easily.

[0018]

[Effects of the Invention] As described in detail above, the gas chromatograph detector of the present invention integrates a thermal ionization detector and a surface ionization detector to simultaneously measure compounds with strong adsorptivity such as amine compounds. Since the measurement conditions of each detector are the same, the accuracy of quantitative measurement of the gas chromatograph is improved.

In addition, since the same amount of sample is sent to each detector without being branched, the measurement sensitivity can be prevented from lowering and sensitivity adjustment between detectors can be facilitated. Become.

In addition, since each detector is integrated, space can be saved in the gas chromatograph measuring device, and a pipe connecting between the detectors is not required, so that an amine compound or the like can be adsorbed. It is also possible to measure compounds with strong properties.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a gas chromatograph detector of the present invention.

FIG. 2 is an example of data measured using the gas chromatograph detector of the present invention.

[Explanation of symbols]

 1 Gas Chromatograph Detector 2 Column Connection Ports 3, 12, 21 Ceramic Insulator 4, 14 Ring Electrode 5 Platinum Emitter 6, 22 Inner Collector 7, 19 Outer Collector 8, 16 Air Supply Port 9, 15 DC Power Supply 10, 23 Power controller 11, 24 Electrometer 13 Quartz nozzle 17 Hydrogen supply port 18 Alkaline source 20 Column 25, 26 Silicone O-ring 30, 31 Transformer

Claims (1)

[Scope of utility model registration request] 1. A detector for a gas chromatograph in which a thermal ionization detector selectively sensitive to an organic nitrogen compound and a surface ionization detector selectively sensitive to an amine compound are integrated.