Recovery rate and precision of determination method for residues of streptomycin, dihydrostreptomycin and kanamycin in milk powder, milk, puffer fish, eel and royal jelly

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2.
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9 Method recovery and precision

Use negative samples to do additive recovery and precision experiments.
After adding different concentration standards to the samples, perform extraction, purification and determination according to this method.
Each additive level is repeated 11 times, streptomycin , dihydrostreptomycin and kanamycin The addition amount is 5.
0ug/kg, 10.
0ug/kg, 20.
0ug/kg and 50.
0ug/kg.
The average recovery rate and relative standard deviation are shown in Table 3-13
.

Table 3-13 Experimental data of recovery rate of streptomycin, dihydrostreptomycin and kanamycin (n=11)

It can be seen from Table 3-13 that at the four addition levels, the average recovery rate of milk and milk powder samples is between 93.
8% and 97.
3%, and the relative standard deviation is between 5.
2% and 6.
8%; the average recovery of puffer fish and eel samples is The rate is between 90.
5%-98.
2%, and the relative standard deviation is between 5.
5% and 7.
8%; the average recovery rate of royal jelly samples is between 92.
7% and 96.
7%, and the relative standard deviation is between 6.
3% and 7.
7%, indicating the method The recovery rate and precision are good
.

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10 Repeatability and reproducibility

Under repeatability test conditions, the absolute difference between the two independent test results obtained does not exceed the repeatability limit (r).
If the difference exceeds the repeatability limit (r), the test results should be discarded and the two individual tests should be completed again.
Determination
.

Table 3-14 Content range and repeatability and reproducibility equation

Related links: Linear range and lower limit of determination of streptomycin, dihydrostreptomycin and kanamycin residues in milk powder, milk, puffer fish, eel and royal jelly