[Simultaneous analysis the residues of 20 hormones in foods of animal origin by liquid chromatography tandem mass spectrometry].

OBJECTIVE

To develop a quick and accurate method for simultaneous determining the multi-residues of hormones in foods of animal origin by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and to investigate these residues in swine, bovine, egg and milk collected from local markets in Shenzhen.

METHOD

The sample was firstly extracted with acetonitrile, and then subjected to solid-phase extraction clean-up using HLB-NH2 cartridges after defatted with hexane, lastly detected by high performance liquid chromatography-tandem mass spectrometry. Identification was achieved by electrospray ionization (ESI) in both positive and negative mode using multiple reaction monitoring. Quantification was performed by internal standard calibration.

RESULTS

The study showed that there was a certain amount of endogenous hormones in collected samples. The limits of quantification were 0.5 - 1.0 microg/kg for 20 hormones in swine, bovine, egg and milk. Average recoveries were 60.4% -118.2%, and the relative standard deviations were 2.5% - 16.2%.

CONCLUSION

This method was quick and accurate which could be used for determination of hormones in foods of animal origin (such as swine, bovine, egg and milk).