HPLC Determination of Residual Amounts of 7 Veterinary Drugs in Aquatic Products

A method of HPLC for the determination of residual amounts of 7 veterinary drugs, including furazolidone, oxolinic acid, nalidixic acid and 4 sulfonamides in aquatic products was proposed. The sample was extracted with acetonitrile and defatted with n-hexane. The residue obtained was taken up with CH3CN-H2O (95+5) and purified by passing through neutral alumina column and C18 column. The eluate was separated on Symmetry C18 column by gradient elution with mixtures of acetonitrile and 0.08 mol·L-1 acetic acid solution in different ratios, and determined with UV detector at the wavelength of 265 nm. Linear relationships between values of peak area ad mass concentration of the 7 veterinary drugs were obtained in the same range of 0.05-10.0 mg·L-1, with detection limits (3S/N) in the range of 0.01-0.04 mg·kg-1. Values of recovery and RSD′s (n=6) of the method found were in the ranges of 68.2%-97.3% and 1.6%-14% respectively.