JPH0611498A - Gas chromatographic method and gas chromatograph mass-spectrometric method - Google Patents

Abstract

PURPOSE:To provide sensibility for DEP with a high sensitivity by turning the DEP thermally stable into derivative using anhydrous trifluoro acetic acid as a reagent for turning into derivatives. CONSTITUTION:DEP as one sort of agricultural chemicals for use in a golf place is very unstable thermally. Anhydrous trifluoro acetic acid as a reagent for turning into derivatives is added to a solution of DEP, and the resultant is left as it is at room temp. for five min. Adding 1-10vol.% trifluoro acetic acid to the DEP solution turns the DEP into derivatives and stabilizes according to the equation C4H8Cl3O4P+CF3COOH C6H7-Cl3F3O5P+H2O. Because of quick and high sensitivity analysis, the temp. rise speed can be set high, and even though the column oven attains the pyrolytic temp. before the DEP flows out, the DEP remains within the column without undergoing decomposition. Accordingly the setting of the temp. rise speed is free from restriction, and also the analyzing time can be shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water quality test, and relates to a simultaneous analysis method capable of treating many specimens in a short time and having high sensitivity.

[0002]

2. Description of the Related Art It is known that DEP, which is a kind of pesticide used in golf courses, is extremely heat unstable. D
Analysis of multi-component systems including EP has
In order to prevent thermal decomposition of P, it is necessary to modify the hardware such as by rapidly raising the temperature of the injection part.

DEP is also very delicate with respect to the temperature rising rate of the column. Because of the high-speed and high-sensitivity analysis, if the temperature rising rate is set fast, the column oven temperature reaches the thermal decomposition temperature before the DEP flows out, and the DEP decomposes in the column. Therefore, the setting of the heating rate is limited and the analysis time is long.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to stabilize a thermally unstable DEP by derivatizing it with trifluoroacetic anhydride, which is a derivatization reagent, and to detect it with high sensitivity.

[0005]

Means for Solving the Problems The problem can be solved by adding trifluoroacetic anhydride, which is a derivatization reagent, to a solution of DEP for derivatization.

[0006]

Function Trifluoroacetic anhydride, which is a derivatization reagent, is added to the DEP solution, and the mixture is allowed to stand at room temperature for 5 minutes. Trifluoroacetic anhydride is derivatized by the following chemical reaction formula by adding 1 to 10% by volume to DEP solution.

[0007]

[Chemical 1]

[0008]

EXAMPLES Examples of the present invention will be described below with reference to Tables 1 and 2 and FIGS.

Table 1 shows the agricultural chemicals used in the golf course used in this example. These were mixed and adjusted to 20 ppm.

[0010]

[Table 1]

FIG. 1 (a) was analyzed using the above sample without adding a derivatizing reagent. Each number corresponds to Table 1.
180 injection temperature to detect DEP
Up to 250 ℃ at 30 ℃ / min, heating rate is 5 ℃
/ Min. Therefore, the analysis time is 40 minutes. In addition, since quantitative analysis requires repeated measurements, it requires a huge amount of time. Similarly, Fig. 1 (b) is a mass chromatogram of the pesticide to which no derivatization reagent was added, but the heating rate was increased to 40 ° C / min in order to shorten the analysis time.
The analysis time was 8.5 minutes, which was reduced to about 1/5.
Was not detected because it was pyrolyzed in the column. (c)
Is 10% by volume trifluoroacetic anhydride according to the invention.
In addition, it is a mass chromatogram analyzed at a temperature rising rate of 40 ° C./min. DEP is derivatized and stably detected with high sensitivity. Table 2 shows the separation / analysis conditions other than the temperature raising conditions of FIGS. 1 (a) to 1 (c).

[0012]

[Table 2]

FIG. 2 (a) is an EI mass spectrum of DEP when a derivatization reagent was added. In FIG. 2 (a), since no molecular ion peak was confirmed, CI measurement of soft ionization was performed to confirm the trifluoroacetyl derivative of DEP. FIG. 2 (b) is a CI mass spectrum of the trifluoroacetyl derivative of DEP. The mass number 353 of the pseudo-molecular ion was detected, and the DEP-trifluoroacetyl derivative could be confirmed.

Next, using the highly sensitive EI method, DEP-
An example in which the quantitativeness of the trifluoroacetyl derivative was examined is shown in FIGS. 3 and 4. Select the mass number 109 of the reference peak,
SIM measurement was performed. FIG. 3 is a mass fragment gram of 1 pg of DEP-trifluoroacetyl derivative. S /
Detected at N = 10. The calibration curve shown in FIG.
It has good linearity with a correlation coefficient of 0.9995 in the concentration range of 30 pg.

[0015]

According to the embodiment of the present invention, 1 pg of DEP is S
/ N = 10 was detected. This is about 1/30 of the conventional amount, and the analysis time was shortened to about 1/5.

[Brief description of drawings]

FIG. 1 is a diagram showing a mass chromatogram of a pesticide used in a golf course.

FIG. 2 is a diagram showing a mass spectrum of a DEP derivative compound.

FIG. 3 is a diagram showing a mass fragment gram of a DEP derivative compound.

FIG. 4 is a diagram showing a calibration curve of a DEP derivative compound.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Yoko Kato 832, Nagakubo, Horiguchi, Katsuta, Ibaraki Pref. 2nd, Nisshin Measurement Engineering Co., Ltd. (72) Naoto Senda, 832 Nagakubo, Horiguchi, Katsuta, Ibaraki Measurement Engineering Co., Ltd. (72) Inventor Toshiaki Takahashi 832 Nagakubo, Horiguchi, Katsuta City, Ibaraki Prefecture

Claims (1)

[Claims] 1. A gas chromatographic method and a gas chromatograph mass spectrometric method which detect DEP with high sensitivity by using trifluoroacetic anhydride as a derivatizing reagent and converting DEP into a trifluoroacetyl derivative.