Selection of analysis conditions for determination of 5 kinds of benzimidazole drug residues in milk and milk powder-determination of purification method

(2) Determination of purification method

1) Pretreatment of solid phase extraction column

The solid phase extraction column was first rinsed with methanol, then washed with water, and then washed with 2 mL of carbonate buffer to fully activate

Table 17-8 The influence of the pretreatment of the solid phase extraction column on the recovery rate

The test results show that the activation effect of the solid phase extraction column is the best when rinsed with 5mL methanol and then washed with 5mL water.

2) Selection of eluent

Add 0.

Table 17-9 The influence of different eluents on the recovery rate

The test results show that when acetonitrile is used as the eluent, the elution effect is the best, and the five benzimidazole drugs can be eluted well

3) Selection of elution speed

Add 0.

Table 17-10 The influence of different elution speeds on the recovery rate

The test results show that when the elution rate is greater than 1.

4) Determination of elution volume

Add 0.

Table 17-11 The influence of elution volume on recovery

The test results showed that after the volume of the elution solvent reached 6 mL, all the five benzimidazole drugs were completely eluted.

5) Selection of concentration temperature

Add 0.

Table 17-12 The influence of concentration temperature on recovery rate

The test results show that the concentration temperature has no significant effect on the recovery rate within the scope of investigation.