Abstract：A simple and sensitive LC-MS/MS method for the determination of baclofen in pork and swine urine was developed.
Samples were extracted with 0.01 mol/L HCl solution, purified with a WCX cartridge and analyzed by LC/MS-MS on a Waters
Acquity BEH C18 column with 0.10% formic acid in water/methanol as the mobile phase by means of gradient elution. Detection was
carried out with an electrospray ionisation (ESI) probe and operated in the positive ion mode. Baclofen was quantified by the internal
standard method. There was a good linearity in the range of concentrations between 1.0 and 100.0 μg/L. The limits of detection for
baclofen were 0.30 μg/kg and 0.10 μg/L in pork and swine urine, respectively. The recoveries from spiked samples were in the
range of 85% to 110% and the relative standard deviations were lower than 10%. These results showed that the method was
simple, rapid, sensitive and reliable for monitoring residual baclofen in pork and swine urine.
2013, Vol. 27 
