Following a protein precipitation with 0.3 mol/l perchloric acid containing internal standard dibekacin at a concentration of 0.6 ¦Ìg/ml, human serum samples containing arbekacin were analyzed using a Hypersil Gold PFP column and a liquid chromatography system. Elution occurred with a gradient of water and acetonitrile, each containing 0.05 % (v/v) trifluoroacetic acid and 0.1 % (v/v) formic acid. Analytes were detected over a 3.25 minute run time using a tandem mass spectrometer with a heated electrospray-ionization (HESI) source in positive ionization mode with selected reaction monitoring (SRM). Matrix effects, carryover, linearity, recovery, precision, and limit of quantification were carefully evaluated.
The limit of quantification for arbekacin was 0.1 ¦Ìg/ml. All simple and total precision CV's were less than 6.2 % . The method was linear from 0.1 ¦Ìg/ml to 45.9 ¦Ìg/ml (slope of 0.973). The mean recovery ranged from 94.7 to 103.8 % . No matrix effects were detected.
This developed and validated LC-MS/MS method allows for the quantification of arbekacin in serum following protein precipitation.