JPH07159409A - Automatic analyzer for trace metal in blood - Google Patents

Abstract

PURPOSE:To achieve higher measuring accuracy and sensitivity by reducing effect of organic matters and coexisting salts when trace metal existing in blood is concentrated in a furnace in an atomic absorption photometer and an automatic analyzer for trace metal in blood which has metal in a graphite furnace, tungsten furnace or the like at an atomizing part. CONSTITUTION:This analyzer has an automatic sampler 10 and a furnace 3, and is provided with a gas controller 7 capable of switching a piping 6 of an oxygen mixed gas and a carrier gas, is capable of the concentration within the furnace including a ashing process. A gas mixed with oxygen flows as carrier gas during the period of ashing. Thus, organic matters and coexisting salts in blood are removed thereby achieving an effect to improve measuring accuracy, sensitivity and prolonging the life of the furnace.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic analyzer for trace metals in blood provided with a metal furnace such as a graphite furnace or a tungsten furnace in the atomization section, and especially chromium which is difficult to detect unless concentration in the furnace is used. In the analysis of trace metals such as manganese in blood, the accuracy of concentration in the furnace was improved and
The present invention relates to a device that significantly improves the sensitivity and reproducibility of a measurement target element.

[0002]

2. Description of the Related Art A conventional automatic in-concentration method will be described by taking an atomic absorption spectrophotometer equipped with a graphite furnace as an example. In-furnace enrichment is applied to elements such as chromium and manganese that are present in blood in very small amounts. First, the sample is injected into the furnace and the drying process (less than 200 ° C) is started.
After completion of the drying process, the sample is injected again to perform the drying process. The sample is concentrated by repeating this process several times. However, in the case of concentrating a sample containing a large amount of organic substances such as blood and coexisting salts in the furnace, using the in-reactor concentration method described above, after concentration is completed Accumulation occurs in. The accumulated residue is
Even if ashing is performed thereafter, it is difficult to completely ash / oxidize, which causes high background absorption. Therefore, it is extremely difficult to obtain an accurate analysis value. On the other hand, as a method for reducing the influence of organic substances, there is a method in which a sample is subjected to acid treatment in advance and pretreatment such as protein removal is performed. However, this increases the number of pretreatment processes, may cause contamination of the target element, requires human labor, and is difficult to automate.

Further, in the measurement, addition of reagents such as a sensitizer and an interference suppressor has been conventionally performed automatically before or after injection of a sample, or both, but in the furnace concentration method. When these reagents are added by using, before the sample injection, it is performed once before the concentration starts, and after the sample injection, it is performed only once after the concentration is completed. In such a method, the effect of adding the reagent decreases as the number of times of concentration increases, which causes poor reproducibility and sensitivity.

[0004]

In the above-mentioned conventional technique, the process of injecting and drying the sample is repeated in the furnace to concentrate the sample, and then ashing is performed. However, in the case of a sample containing a large amount of organic substances or coexisting salts such as blood, this method accumulates the organic substances and coexisting salts, making it difficult to completely ash / oxidize the organic substances and remove the coexisting salts during ashing. Accumulation of them occurs. Furthermore, when a reagent such as a sensitizer and an interference suppressor was added, it was possible to add the reagent automatically in the case of concentrating in a furnace. Therefore, the effect of reagent addition gradually decreased as the number of times of concentration increased, which was a cause of poor reproducibility and sensitivity.
In the present invention, the sample injection, the drying and the ashing process (200 ° C. or higher) are repeated in the furnace to concentrate the sample. Therefore, complete ashing / oxidation of organic substances and removal of coexisting salts can be carried out, and measurement is performed. It is intended to improve accuracy and extend the life of the furnace. Further, reagents such as a sensitizer and an interference suppressor are intended to improve the measurement accuracy, sensitivity and reproducibility by automatically adding the reagents each time the concentration process is completed.

[0005]

In order to achieve the above object, the present invention provides an incineration process (200) in addition to the in-furnace concentration process that has been conventionally used in the analysis of trace metals in blood.
By subjecting the carrier gas to oxygen gas at the time of ashing, complete ashing / oxidation of organic substances can be performed. This reduces high background absorption due to the effects of organic substances and coexisting salts, and also prevents the accumulation of organic residue in the furnace, thus improving the measurement accuracy and extending the life of the furnace. There is. Regarding the addition of the sensitizer and the interference suppressor, it is possible to automatically add each time the concentration process is completed before the sample is injected or before the ashing, and the sample addition effect is further improved. This enables measurement with good sensitivity and reproducibility.

[0006]

In the structure of claim 1, the sample injection, drying, and ashing processes (200 ° C. or higher) are repeatedly concentrated to prevent the accumulation of organic residue in the blood in the high temperature furnace.
In addition, the coexisting salt is removed to improve the measurement accuracy.

According to the constitution of claim 2, at the time of ashing, oxygen is mixed with the carrier gas to promote the oxidation of the organic substance and completely ash it.
It improves the measurement accuracy and extends the life of the furnace.

In the structure of claim 3, the addition of reagents such as a sensitizer and an interference suppressor is carried out before the sample injection or the ashing process is started each time the concentration process is completed, and the effect is always maintained. By making it constant, sensitivity and reproducibility are improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an atomic absorption spectrophotometer equipped with a metal such as a graffiti furnace 3 or a tungsten furnace in an atomization part 1 and an automatic trace metal analyzer in blood. Even Zeeman method for background correction OK, or may be a D ₂ method or S-R method.

Serum is used as a sample for measurement, and the number of times of concentration is 10 times. The sample may be whole blood.

After the measurement is started, the nozzle 17 automatically injects the sample into the furnace from the autosampler 10 to start the drying process. After the drying is completed, the addition of the sensitizer and the interference suppressor is automatically performed like the sample. The reagent may be added before the sample injection. After that, the ashing process begins,
At this time, the gas control device 7 switches the carrier gas 6 from argon gas to argon gas containing 10% oxygen. The amount of oxygen mixed may vary depending on the content of organic substances. This gas completely ashes / oxidizes organic matter in serum. Further, since the sensitizer is added, the ashing temperature can be raised and the coexisting salt can be removed. The process until the end of ashing is referred to as one process of concentration. After repeating this operation 10 times, the atomization process starts.

In the conventional concentration method, the concentration has been performed by repeating the process until drying. However, in the case of measuring a serum sample, this method could not accurately concentrate due to the influence of organic substances and coexisting salts, and an accurate analysis value could not be obtained. In the present invention, since the concentration including the ashing process is performed, their influences are reduced and the measurement accuracy is improved.

An example of measuring chromium by the method described above is shown in FIG. From the results, it was possible to accurately concentrate up to 3 times in the case of using argon gas only 2 at the time of ashing, whereas it was 10 in the case of using oxygen-mixed argon gas 1
The reproducibility is good even if the concentration is performed once, and there is a high correlation between the number of concentration and the absorbance. Therefore, by performing this operation, a trace amount of chromium in serum can be sufficiently concentrated in the furnace, and reliable analysis can be performed. The measurement results are shown in Table 1. The concentration of chromium in serum is about 0.1ppb-0.15p
It was pb and was in good agreement with the analysis value.

[0014]

[Table 1]

[0015]

Since the present invention is constructed as described above, it has the following effects.

Concentration including ashing process is performed in the furnace,
Further, by mixing oxygen with a carrier gas during ashing, complete ashing / oxidation of organic substances and removal of coexisting salts can be performed in the case of directly analyzing trace metals in blood. Therefore, the measurement accuracy can be improved and the life of the furnace can be extended. Further, by adding reagents such as a sensitizer and an interference suppressor each time the concentration is completed, variations in addition of the reagents are reduced, and sensitivity and reproducibility are improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment.

FIG. 2 is a diagram showing a measurement example.

[Explanation of symbols]

1 ... Atomization part, 2 ... Optical system, 3 ... Furnace, 4 ... Ring, 5 ...
Hollow cathode lamp, 6 ... Carrier gas pipe, 7 ... Gas control device, 8 ... Argon gas pipe, 9 ... Oxygen gas pipe, 10
… Auto sampler, 11… Main unit control system,
12 ... Reflective mirror, 13 ... Collimating mirror, 14 ...
Photomal, 15 ... Slit, 16 ... Polarizer, 17 ... Nozzle, 18 ... Optical path.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Koichi Uchino 832 Nagakubo, Horiguchi, Katsuta City, Ibaraki Prefecture

Claims (3)

[Claims] 1. A device for performing analysis by utilizing an absorption phenomenon at the time of atomization of an element, which is equipped with a metal furnace such as a graphite furnace or a tungsten furnace in an atomization part, and trace metals existing in blood in the furnace. In the case of concentrating and analyzing, in addition to the drying process at the time of concentrating, an ashing process (200 ° C. or higher) is performed to reduce the influence of organic substances and coexisting salts. 2. An automatic analyzer for trace metals in blood according to claim 1, wherein oxygen gas is mixed with carrier gas during ashing to completely ash / oxidize organic matter. 3. The method according to claim 1, wherein when a reagent such as a sensitizer and an interference suppressor is added, it is automatically added before drying or ashing each time one process of concentration is completed. Automatic trace metal analyzer in blood characterized by: