GB/T 22146-2008Determination of roxarsone in animal feeds - High performance liquid chromatography (English PDF)

4.1 Methanol

chromatographically pure.

4.2 dipotassium hydrogen phosphate solution (20g/L)

Weigh 20g dipotassium hydrogen phosphate (K2HPO4) dissolved in water, and dilute to 1000mL.

4.3 copper sulfate solution (100g/L)

Weigh 10g of copper sulfate (CuSO4 · 5H2O) dissolved in water, and dilute to 100mL.

4.4 Solid phase extraction column eluent and the eluent

1 4.4.1 eluent. 6.80g/L sodium acetate - methanol solution. Weigh 6.80g of sodium acetate (Na2C2H3O2 · 3H2O) in a beaker, add

800mL dissolve into the water, with 10% acetic acid adjusted to pH 7, was added 53mL of methanol, dilute to 1000mL, 4 °C storage.

4.4.2 eluent 2

anhydrous methanol.

4.4.3 eluent

5% methanol solution of formic acid, formic acid 5mL draw with anhydrous methanol to 100mL.

4.5 Mobile phase

4.5.1 A solution

6.98g/L potassium dihydrogen phosphate solution containing 0.1% formic acid, weighed 6.98g potassium dihydrogen phosphate (KH2PO4) in a beaker

In, dissolved in water, formic acid is added 1mL solution and dilute to 1000mL.

4.5.2 B solution

dry methanol.

4.6 Roxarsone standard solution

4.6.1 Standard stock solution

Weigh accurately roxarsone standard (content >=99%) 500mg, placed 1000mL brown volumetric flask

Dipotassium hydrogen phosphate solution (4.2) sonication to prepare a 500µg/mL standard stock solution, stored in a refrigerator at 4 °C.

4.6.2 Standard working solution

draw stock standard solution (4.6.1) 0.2,0.4,0.6,0.8,1.0mL are brown to 50mL volumetric flask,

And diluted with potassium phosphate dibasic solution (4.2) to the mark. Standard operating concentration were 2.0,4.0,6.0,8.0,10.0µg/mL of

As a liquid.