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Analysis of testosterone propionate from aquatic products with off-line subcritical fluid extraction-high performance liquid chromatography system

An off-line subcritical fluid extraction method has been developed for the determination of testosterone propionate residues in aquatic products. Subcritical 1, 1, 1, 2-tetrafluoroethane (R134a) was applied to the analysis of testosterone propionate in aquatic products. The analytes were extracted from the matrix by subcritical R134a and analysed by liquid chromatography. Orthogonal design experiments were applied to optimize the variables on the basis of single factor experiments. The optimized extracting conditions were as follows: pressure 140 bar, temperature 296 K, time 40 min, co-solvent methanol (2 ml) and flow rate 1.0 L/min (standard state). The residues were purified by liquid-liquid extraction with petroleum ether for HPLC analysis (detection limit 0.1 µg/ml, S/N=3). The average recovery of testosterone propionate was greater than 90%, and the RSD was less than 5%.