The invention discloses a method for performing
high performance liquid chromatography with
fluorescence detection on residues of
ampicillin and
amoxicillin in an aqueous product, which belongs to the field of
food safety detection. The method comprises the following steps of: 1, preparing
standard solution; 2, performing sampling, namely, uniformly dividing not less than 500 grams of mashed sample into two parts and storing the sample at -18 DEG C; 3, performing extraction, namely, adding 5 grams of sample into
sodium dihydrogen
phosphate, adding water for
dissolution until the volume is fixed to be 500 milliliters, preparing 30 milliliters of extract, performing secondary homogenization and
centrifugation, extracting supernate and adding a
trichloroacetic acid into the supernate for later use; 4, performing purification, namely, rinsing a small
solid-extraction column sequentially with
methanol,
distilled water and the
trichloroacetic acid at the controlled speed of 20 drops per minute, performing complete pumping, and performing
elution with 5 milliliters of
ethanol; and 5, performing derivation, namely, performing blow-
drying with
nitrogen at 40 DEG C, adding the
trichloroacetic acid and 7 percent
formaldehyde solution into 0.5 milliliter of
standard solution for uniform mixing, placing the
mixed solution in a sealing way into a boiling water bath to perform heating for 30 minutes, eluting the solution with ecetonitrile after the solution is cooled until the volume is fixed to be 1 milliliter, and performing
filtration for the liquid
chromatography, wherein the limit of detection is less than 5 mu g / kg.