Determination of octylphenol, nonylphenol, bisphenol A, diethylstilbestrol, estrone, 17α-ethinyl estradiol, 17β-estradiol, and estriol residues in aquatic products-Gas chromatography-mass spectrometry (3)

8 Calculation and presentation of results

The residual amount of the drug to be tested in the sample is calculated according to formula (1.

where:

X - the residual amount of the tested component in the sample, in micrograms per kilogram (μg/kg);

Cs - the concentration of the tested component in the standard solution, in nanograms per milliliter (ng/mL); 

A——the peak area of ​​the tested component in the sample solution;

As - the peak area of ​​the measured component in the standard solution;

V——The constant volume of the sample solution, the unit is milliliter (mL);

m—the mass of the sample, in grams (g.

The calculation result needs to deduct the blank valu.

9 Sensitivity, accuracy and precision of detection methods

1 Sensitivity

The detection limit of this method: octylphenol and diethylstilbestrol are respectively 2 μg/kg, nonylphenol and bisphenol A are respectively 1 μg/kg, estrone, 17α-ethinyl estradiol, 17β-estradiol, The estriol was 3 μg/kg, respectively; the limit of quantification: octylphenol and diethylstilbestrol were 5 μg/kg, respectively, nonylphenol and bisphenol A were 3 μg/kg, estrone, 17α-acetylene Estradiol, 17β-estradiol, and estriol were 0 μg/kg, respectivel.

2 Accuracy

Octylphenol and diethylstilbestrol are in the range of 5 μg/kg～10 μg/kg added concentration, and the recovery rate is 70%～110%; Nonylphenol and bisphenol A are in the added concentration range of 3 μg/kg～6 μg/kg, the recovery is The recovery rate is 70%~110%; the recovery rate of estrone, 17α-ethinyl estradiol, 17β-estradiol, estriol is 70%~110% in the range of 0 μg/kg~20 μg/kg added concentratio.

3 Precision

The intra-assay relative standard deviation of this method is less than or equal to 15%, and the inter-assay relative standard deviation is less than or equal to 20.