JPH09223479A - Mass spectrometry device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sample holder for a mass spectrometry device capable of easily, quickly performing the operation of coating of a sample, drying, vaporization, washing or the like on the outer surface of the sample holder by forming the sample holder in a direct sample introducing part in the shape of rod whose surface has high wettability. SOLUTION: A direct sample introducing part 1 is constituted so that a sample holder 4 and a cap 5 are detachably fit to the edge part of a stainless steel probe 3 having a heater 2. The sample holder 4 has a flange for inserting into the probe 3, is formed in the shape of rod whose surface has high wettability, and the outer diameter of the flange is fit to the inner diameter of the edge part of the prove 3. Operation of coating of a sample, drying, vaporization, washing or the like is easily, quickly performed on the outer surface of the sample holder 4, and since washing is easy, no component is left by washing, and the sample holder for a mass spectrometry device capable of preventing the problem caused by contamination is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mass spectrometer equipped with a direct sample introduction section.

[0002]

2. Description of the Related Art A mass spectrometer is a high-sensitivity analyzer that obtains information on the number of molecules and the structure of a sample substance by detecting and recording a sample ionized by various methods according to the number of mass / charge. The configuration of the mass spectrometer is roughly as follows: sample introduction section → ionization section → ion separation section → ion detection section → recording section.

As the sample introducing section, various techniques such as a direct chromatography introducing method and a direct sample introducing method have been devised. Among them, the apparatus having the structure shown in FIG. 1 is conventionally used as an apparatus for performing the direct sample introducing method. It is commonly used.

As shown in FIG. 1, a conventional direct sample introduction section 1
Is mainly composed of a stainless steel probe 3 having a heater 2 for heating and having a diameter of about 8 mm, and its tip is formed in a concave shape, and the sample cup 4 is inserted into this concave portion. There is. The sample cup 4 (also called the sample pot) is made of Pyrex glass or quartz glass with a diameter of about 1 mm, and the sample solution is applied to the inner wall in advance.
It is dried, attached, and fitted and inserted into the concave portion of the probe 3.
Further, as shown in the figure, a stainless steel cap 5 is attached so as not to close the opening of the sample cup 4. After inserting the probe 3 charged with the sample in this way into the ion source 6 (see FIG. 3) of the mass spectrometer M, the heater 2 of the probe 3 heats the sample cup 4 to a set temperature at a set temperature rising rate. Directly ionizes the vaporized sample 6
Introduce within.

[0005]

However, there are various problems in applying and drying the sample on the inner wall of the sample cup 4 as in the prior art.

[0006] Manually injecting a sample solution into a fine sample cup 4 having a diameter of about 1 mm using a microsyringe or the like is a very delicate operation and requires a lot of labor and time for an operator.

Further, the solvent in the sample solution is blown off by natural drying, but since the opening of the sample cup 4 is very small, it takes 5 minutes to several hours to completely dry it, depending on the type of solvent. It is also a cause of making the entire time redundant. Also, sometimes applied to concentrate the sample solution.
The drying is repeated, but it takes several times longer.

The state after drying is also not constant, as shown in FIG.
As shown in (a), the sample is not uniformly deposited on the inner wall of the sample cup 4, or is deposited at a completely irregular position as shown in FIG. Even when heated at 2, the temperature and time of vaporization varied depending on the place where the sample was attached, and the vaporization did not occur at once, so the analysis peak widened and it was not possible to obtain good analysis results.

Further, the sample cup 4 is expensive, and is washed and reused after the analysis is completed. However, it is not easy to wash such a minute closed tube, and sometimes residual sample is contaminated. Cause the next analysis to be disturbed. Further, the cup is baked to completely remove the sample components from the washed sample cup 4,
In this case, the sample cup 4 made of Pyrex glass
There is an inconvenience that distortion or the like may occur.

The present invention has been made in view of the above problems of the conventional apparatus, and provides a mass spectrometer having a direct sample introducing section capable of solving all the problems of the related art with a simple structure. To provide.

[0011]

In order to achieve the above object, a mass spectrometer according to the present invention applies a sample solution to a sample holder 4 at the tip of a probe 3 and inserts it directly into an ion source 6. The sample holder 4 of the direct sample introduction part 1 is a rod-shaped body having a good wettability, which is a mass spectrometer provided with the direct sample introduction part 1 for ionizing the sample.

The "rod-like body" here is not limited to a cylindrical rod-like shape, and may have an elliptical or polygonal cross section, or may be a flat plate-like shape.

The sample adheres to the surface of the sample holder 4 which is a rod-shaped body due to its good wettability. As a result, the work of coating and drying the sample on the sample holder 4 can be easily performed in a short time, the adhesion state of the sample is improved, and good analysis can be performed, and the cleaning after the analysis is simple and complete. It will also be easy to wash.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the mass spectrometer according to the present invention will be described below.

FIG. 3 schematically shows one structural example of the mass spectrometer according to the present invention, and particularly shows a structural example near the ion source. The mass spectrometer mainly comprises a sample introducing unit 1, an ion source 6 into which a sample is introduced and vaporized, and a mass analyzing unit M which analyzes the ionized target sample component. The present invention is particularly characterized by the configuration of the direct sample introduction unit 1, and in other configurations, there is no change in the conventional device.

FIG. 4 shows an example of the structure of the direct sample introducing section which constitutes the characteristic structure of the present invention. FIG. 4 corresponds to FIG. 1 of the conventional configuration. The direct sample introduction part 1 is mainly composed of a stainless steel probe 3 having a heater 2 for heating and having a diameter of about 8 mm, and the tip part thereof is formed in a concave shape, and the sample holder 4 is inserted into this concave part. It has become so.

The sample holder 4 has a flange formed for the convenience of insertion, and is manufactured by matching the diameter so as to be fitted and fixed to the inner diameter of the concave portion at the tip of the probe 3, and is made of quartz glass or Pyrex. Made of ceramics or the like. Fine irregularities are formed on the surface of the sample holder 4. For example, it is in the state of frosted glass, scratches are formed, fine grooves are formed, or the fine surface irregularities originally possessed by materials such as ceramics are used, or they are wet by chemical treatment. The sexuality has been improved.

A sample solution is applied to the surface of the sample holder 4 in a state where the sample holder 4 is attached to the probe 3 or before the attachment. The application method is not particularly limited and may be dropped by using a microsyringe as in the conventional case, or the sample holder 4 may be directly immersed in the sample solution for easy application. Thus, the sample coated on the surface is dried to remove the solvent, but the sample holder 4 according to the present invention does not have a fine cup shape as in the prior art, but the sample holder 4 can be dried from the surface, so that it can be dried in a short time. Can be made. Also, it has become possible to use blast or the like for drying. If necessary, the application and drying are repeated to concentrate the sample.

In the sample holder 4 to which the sample is attached substantially uniformly in this way, the cap 5 is attached from above the sample holder 4 with the sample holder 4 exposed, and the sample holder 4 is fixed. After inserting the probe 3 charged with the sample in this way into the ion source 6 of the mass spectrometer M, the heater 2 of the probe 3 monitors the temperature by a platinum sensor (not shown) or a temperature measuring means such as a thermocouple to set and increase the temperature. The sample holder 4 is heated to the set temperature at a temperature rate, the target component is evaporated and vaporized, and the target component is directly introduced into the ion source 6 and analyzed by the mass spectrometric section M.

After the analysis is completed, the probe 3 is pulled out and the sample holder 4 is washed. Since it is only necessary to wash the outer surface of the rod-shaped body instead of washing the inside of a fine closed tube as in the conventional case, it is possible to easily and completely wash. It is also easy to use ultrasonic cleaning or the like. Since the sample components can be almost completely removed by washing, no adverse effects such as contamination will occur even when reused for the next analysis.

The shape of the sample holder 4 according to the present invention is not limited to that shown in FIG. The structure of FIG. 4 is a structure that emphasizes that it can be realized at low cost by using the conventional structure as it is, and it is possible to vaporize the sample on the surface of the sample holder 4 at a stretch and obtain a sharper analysis peak. If an emphasis is placed, a part of the heater 2 may be formed inside the sample holder 4, or a good thermal conductor such as metal may be embedded inside the holder 4 so that the heat of the heater 2 can be conducted well. desirable. Of course, the sample holder 4 may be integrally formed at the tip of the probe 3. Further, as shown in FIG. 5, a sample holder 4 having a plate-shaped tip with a heater 2 embedded therein is used.
It is good. By using a plate shape, the distance between the sample and the heat source becomes closer, and vaporization is easy.

Further, the ion separator 6 and the molecular separator 7 are commonly used in this type of mass spectrometer.
The chromatographic column 8 can also be connected via the above, and it does not prevent that the direct sample introduction method and the chromatograph direct connection sample introduction method can be switched. Similarly, a chemical ionization method (C
I method) and electron impact ionization method (EI method), etc. can be carried out, and it is not hindered to attach the reaction gas introduction facilities 9 and 10 to the ion source 6. In addition, the configuration can be appropriately changed without changing the gist of the present invention.

[0023]

According to the present invention, all operations such as application, drying, vaporization, and cleaning of the sample can be performed on the outer surface of the sample holder 4, so that the operation can be performed easily and in a short time, and the remaining cleaning can be performed. It was possible to prevent harmful effects such as contamination due to the components.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a conventional direct sample introduction unit.

FIG. 2 is a diagram showing a state of attachment of a sample in a conventional sample cup.

FIG. 3 is a diagram showing a configuration example of a mass spectrometer according to the present invention.

FIG. 4 is a diagram showing a configuration example of a direct sample introduction unit according to the present invention.

FIG. 5 is a diagram showing a configuration example of a direct sample introduction unit according to the present invention.

[Explanation of symbols]

 M ... Mass spectrometric section 1 ... Direct sample introduction section 2 ... Heating heater 3 ... Probe 4 ... Sample holder 5 ... Cap 6 ... Ion source 7 ... Molecular separator 8 ... Column 9 ... Reaction gas introduction tube 10 ... Reaction gas reservoir P ... Exhaust system

Claims (1)

[Claims] 1. A mass spectrometer equipped with a direct sample introducing unit for applying a sample solution to a sample holder at the tip of a probe, inserting the sample solution directly into an ion source, and then ionizing the sample, said direct sample introducing unit. The sample holder is a rod-shaped body having a good wettability on its surface.