JPH05190136A - High frequency inductive coupling plasma analyzing device - Google Patents

Abstract

PURPOSE:To improve the measurement sensitivity with the simple constitution. CONSTITUTION:A heating means for heating the wall A of a spray chamber 8 opposed to the injection hole of a nebulizer 3 by a heater 21, etc., is installed. In this constitution, the heater 21 is allowed to conduct, from an electric power source, and in the state where the wall A part is heated to a proper temperature, a sample liquid is jetted into the spray chamber 8 from the nebulizer 3. When the atomized mist droplets of the sample liquid approach the wall A part in heated state, the particle diameter is reduced further by the heat on the wall surface. The sample liquid droplet whose particle diameter is reduced and tends to be easily loaded on the gas stream formed along the wall surface, and then introduced into a plasma torch 1 through an introducing pipe 9, loaded on this stream, and ionized by the method described in the conventional examples, and mass-analyzed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid sample atomizing device for atomizing a liquid sample, and more particularly to a high frequency inductively coupled plasma mass in which a high frequency inductively coupled plasma (ICP) ion source and a mass spectrometer are combined. Analyzer (ICP-M
The present invention provides an effective liquid sample atomizing device for use in S).

[0002]

2. Description of the Related Art FIG. 2 shows an example of ICP-MS.

In the figure, 1 is a plasma torch made of an electrically insulating material such as quartz around which a high frequency induction coil 2 is wound, 3 is an inert gas supplied from a gas supply source (not shown), for example,
It is a nebulizer for spraying a sample solution together with an argon gas G. Reference numeral 4 is a high-frequency power source for applying a high-frequency voltage to the coil 2, and reference numeral 5 is a sample bottle that contains a sample solution 6 and is connected to the nebulizer 3 via an introduction tube 7. Reference numeral 8 is a spray chamber, and 9 is an introduction tube for introducing the sample solution 6 sprayed by the nebulizer 3 into the spray chamber into the plasma torch 1. 10 is a case for shielding the high frequency from the coil 2,
This case is connected to the ground side of the high frequency power supply 4. 11 is a sampling cone 12 and a skimmer 13,
An interface consisting of 14 and a mass spectroscope 15 are provided with a mass spectrometric system 16 inside. Reference numeral 17 denotes an electrode group for accelerating and converging ions to introduce them into the mass spectrometric system 16. Reference numeral 18 is an oil diffusion pump for maintaining a high vacuum inside the mass spectrometer 15, and 19 and 20 are the nozzle 1
Space A1 between 2 and skimmer 13 and skimmer 13 and 1
4 is an oil rotary pump for exhausting the space A2 between the four.

In such a structure, the plasma torch 1
Argon gas is supplied to the coil from a gas supply source (not shown). In this state, when high frequency power is applied from the high frequency power source 4 to the coil 2 to form a high frequency magnetic field, a high frequency induction plasma (hereinafter referred to as plasma) P is generated. Occur. The sample liquid 6 is atomized into the plasma P from the nebulizer 3 and the sample is ionized. The sample ions in this plasma are sampling cone 12, each skimmer 1
Enter the interface 11 through 3, 14.
Ions that have entered this interface are electrode group 17
Are accelerated and converged by and are introduced into the mass spectrometric system 16 for mass spectrometric analysis. As this mass analysis system, either a Q-pole type or a magnetic field type may be used.

[0005]

In the above-mentioned conventional technique, high-sensitivity analysis has become possible, but further improvement in sensitivity is required.

Therefore, the present invention has been made in view of the above points, and an object thereof is to improve the measurement sensitivity with a simple structure.

[0007]

In order to achieve the above object, a high frequency inductively coupled plasma analyzer according to the present invention comprises a sprayer for spraying a liquid sample from a spray hole into a spray chamber, and a sample atomized by the sprayer. In the high frequency inductively coupled plasma analyzer that is introduced into the plasma torch,
It is characterized in that a means for heating the wall surface facing the spray hole in the spray chamber is provided.

[0008]

In the present invention, since the means for heating the wall surface facing the spray hole of the nebulizer for spraying the liquid sample is provided in the spray chamber, the sample liquid which collides with the wall of the spray chamber and becomes a liquid film and is discharged is reduced. Therefore, most of the sample liquid sprayed from the nebulizer into the spray chamber can be introduced into the plasma torch.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a schematic enlarged view showing a main part of an apparatus according to an embodiment of the present invention, and those having the same numbers as those in FIG. 2 show the same components.

The apparatus of FIG. 1 is different from the conventional example of FIG. 2 in that a heating means for heating the wall A of the spray chamber 8 facing the spray hole of the nebulizer 3 with a heater 21 or the like is provided.

In such a structure, the sample solution is sprayed from the nebulizer 3 into the spray chamber 8 while the heater 21 is energized from a power source (not shown) so that the wall A is heated to an appropriate temperature. . When the atomized droplets of the sample liquid approach the heated wall A, the heat of the wall causes
Further, the particle size is reduced. The sample droplets having the smaller particle size easily ride on the flow of gas formed along the wall surface, and are introduced into the plasma torch 1 through the introduction pipe 9 along with this flow, as described in the conventional example. Is ionized and mass spectrometrically analyzed. In the prior art in which the wall A portion is not heated, a large fog droplet comes close to the portion A and adheres to the wall surface. The sample solution can be transferred to the plasma torch.

In the above-described embodiment, the heater is provided on the wall A of the spray chamber facing the spray hole of the nebulizer, but the heater is not limited to this. Irradiation, or
Infrared rays may be applied to the infrared absorbing material applied or attached to the outside of the wall A portion, or the wall A portion may be heated using a heating medium such as heated oil.

[0014]

As described in detail above, according to the present invention, most of the sample liquid can be transferred to the plasma torch by the heating means provided on the wall A of the spray chamber, and with a simple structure, The measurement sensitivity can be improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a main part of an apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic view of a main part of a conventional device.

[Explanation of symbols]

 1: Plasma torch 2: High frequency induction coil 3: Nebulizer 4: High frequency power supply 5: Sample bottle 6: Sample liquid 7, 9: Introducing tube 8: Spray chamber 10: Case 11: Interface 12: Sampling cone 13: First skimmer 14: Second skimmer 15: Mass spectrometer 16: Mass spectrometer 17: Electrode group 18: Oil diffusion pump 19, 20: Oil rotary pump 21: Heater

Claims (1)

[Claims] 1. A sprayer for spraying a liquid sample into a spray chamber from a spray hole, and a high-frequency inductively coupled plasma analyzer for introducing a sample atomized by the sprayer into a plasma torch. A high-frequency inductively coupled plasma analysis device, characterized in that a means for heating a wall surface facing to is provided.