JPH11101788A - Gas chromatograph apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the adsorption of a sample to an insert to enhance detection sensitivity and determination accuracy by covering the inner wall surface of the insert with a metal low in reactivity. SOLUTION: A metal film 21 composed of a metal low in reactivity coats the inner wall surface of the glass insert 20 provided in a sample gasifying chamber 10. At the time of analysis, a sample is sucked into a syringe and the needle of the syringe is allowed to pierce the septum 12 of the sample gasifying chamber 10 to inject the sample into the sample gasifying chamber. The injected sample is heated by a heater 13 to be gasified within a glass insert 20 and introduced into a column while carried by carrier gas. The coating of the contact surface with org. matter (the sample in a gas chromatograph) with the metal film low in reactivity results in the reduction of the active point of M-O or M-OH (wherein M is a metal element) to effectively prevent the adsorption of the sample.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sample vaporization chamber of a gas chromatograph.

[0002]

2. Description of the Related Art FIG. 3 is a schematic view of a sample vaporizing chamber conventionally used in a gas chromatograph. In the figure, reference numeral 11 denotes a vaporization chamber main body, which is a carrier gas inlet 1
1a, a purge port 11b, and a column connection port 11c are provided, and a septum 12 is attached to an upper portion thereof. A heater 13 is wound around the vaporization chamber main body 11, and the heater 13 is controlled by a temperature control unit 14.

[0003] A capillary column 15 is connected to a column connection port 11 c at the bottom of the vaporization chamber main body 11, and the other end of the capillary column is connected to a detector 16.

[0004] A cylindrical glass insert 20 is provided inside the vaporization chamber main body 11, and a sample is vaporized inside the glass insert 20. That is, by vaporizing the sample inside the glass insert 20, the vaporized sample is introduced into the column without contacting the metal surface of the sample vaporization chamber main body 11. Since the glass insert 20 is detachably attached as described above, when the sample is soiled, the glass insert 20 can be removed for cleaning or replacement.

[0005]

By using a glass insert, contamination of the sample vaporization chamber can be prevented and cleaning can be easily performed. However, the glass surface has -OH
When analyzing a sample containing polar molecules, the polar molecules are adsorbed on the inner surface of the glass insert as shown in FIG. 4 depending on the sample due to the hydrogen bond between the -OH group and the polar molecules. And the amount of detection is reduced.

Accordingly, an object of the present invention is to provide a gas chromatograph analyzer capable of analyzing a sample having a high adsorptivity without any problem.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a gas chromatograph analyzer of the present invention is a gas chromatograph having a sample vaporization chamber. Characterized by being coated with a metal. Less than,
This gas chromatograph will be described using an embodiment.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view of a sample vaporization chamber of a gas chromatograph apparatus showing one embodiment of the present invention. The same parts as in the conventional example shown in FIG.

In the sample vaporization chamber 10 of the present invention, the inner wall surface of a glass insert 20 provided in the sample vaporization chamber is coated with a thin gold film 21 which is a metal having low reactivity as shown in FIG. Such low-reactivity metals include:
In addition to gold, a metal film such as platinum can be used. The coating of these metal films can be formed by a thin film forming technique such as vacuum evaporation.

[0010] In the analysis of the gas chromatograph, an analyst inhales a sample into a syringe and injects the sample into the sample vaporization chamber by passing the needle of the syringe through the septum 12 of the sample vaporization chamber 10. The injected sample is vaporized in the glass insert 20 by being heated by the heater 13 and introduced into the column along with the flow of the carrier gas.

Here, in general, the adsorption of an organic substance on the metal surface is caused by the effect of an oxide layer on the metal surface and the influence of moisture.
This is because O or M-OH (M is a metal element) becomes an active site.

On the other hand, coating a surface in contact with an organic substance (a sample in a gas chromatograph) with a less reactive gold thin film or the like reduces active points such as MO and M-OH, and adsorbs the sample. It is effective for prevention.

Although the conventional example uses an insert made of glass, according to the present invention, the material of the insert need not be limited to glass. In other words, if a low-reactivity metal is coated, the material of the insert does not need to be glass, and there is also an advantage that an insert of another material which was previously unsuitable for use as an insert can be used. Have.

For example, by using an insert using metal (for example, stainless steel) instead of glass, an insert having much better workability than glass and having high mechanical strength can be manufactured at low cost. For example, it is only necessary to cut out and coat a metal pipe.

This embodiment will be summarized below. (1) A gas chromatography apparatus having a sample vaporization chamber, wherein a metal material is used as an insert to be installed in the sample vaporization chamber, and the inner wall surface is coated with a low-reactivity metal. ◎
According to this aspect, there is a specific effect that an insert having high workability and mechanical strength can be obtained at a low price.

[0016]

As described above, in the sample vaporization chamber of the present invention, since the inner wall surface of the insert is coated with a low-reactivity metal film, adsorption of the sample to the insert is reduced, and the detection sensitivity is reduced. And the precision of quantification can be increased.

[Brief description of the drawings]

FIG. 1 is a schematic view of a sample vaporization chamber of a gas chromatograph according to one embodiment of the present invention.

FIG. 2 is a perspective view of the glass insert in FIG.

FIG. 3 is a schematic diagram of a sample vaporization chamber of a conventional gas chromatograph device.

FIG. 4 is a diagram showing adsorption of a sample on a glass surface.

[Explanation of symbols]

 10: Sample vaporization chamber 11: Vaporization chamber main body 13: Heater 14: Temperature control unit 15: Capillary column 20: Glass insert 21: Gold thin film

Claims (1)

[Claims] 1. A gas chromatograph apparatus having a sample vaporization chamber, wherein an inner wall surface of an insert mounted in the sample vaporization chamber is coated with a low-reactivity metal.