Analysis of tilmicosin in swine liver extracts by liquid chromatography/atmospheric pressure chemical ionization mass spectrometry.
Tilmicosin is a semisynthetic macrolide antibiotic used in the treatment of respiratory disease in cattle and swine. The technique of liquid chromatography/atmospheric pressure chemical ionization mass spectrometry (LC/APCI-MS) was employed in an on-line capacity for the analysis of tilmicosin in extracts from spiked swine liver. Increasing the potential in the cone/skimmer region of the ion source resulted in an increased abundance of unique structurally indicating fragment ions of tilmicosin. Three ions, [M+H]+ and two diagnostic fragment ions were chosen for confirmation of the presence of tilmicosin in swine liver tissue extracts using the mass spectrometer in selected-ion monitoring mode. The ion abundance ratios arising from any given combination of ions in data acquired from extracts of swine liver tissue spiked with tilmicosin at 5 and 10 ppm were within +/- 10% of the corresponding mean standard abundance ratio, and duplicate sample analyses exhibited < 10% relative standard deviation. These results suggest the potential for the application of LC/APCI-MS as a confirmatory technique for tilmicosin in swine liver.
Eli Lilly and Company, Lilly Research Laboratories, Greenfield Laboratories, Indiana 46140-0708, USA.
D E
DE
Kiehl
A S
AS
Kennington
D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002853:Chromatography, Liquid; D008099:Liver / Q000737:chemistry*; D018942:Macrolides; D013058:Mass Spectrometry; D010316:Particle Size; D013056:Spectrophotometry, Ultraviolet; D013552:Swine; D014020:Tissue Extracts / Q000032:analysis; D015645:Tylosin / Q000031:analogs & derivatives* / Q000032:analysis
D000900:Anti-Bacterial Agents; D018942:Macrolides; D014020:Tissue Extracts; C052319:tilmicosin; D015645:Tylosin