Determination of penicillin G in feeds by liquid chromatography with solid-phase extraction.
A liquid chromatographic method was developed for the determination of penicillin G in feeds. The method involves extraction of penicillin G with methanol, concentration under a stream of nitrogen, and cleanup using Phenomenex Strata-X solid-phase extraction cartridge. Analyte separation and quantification were achieved by gradient reversed-phase liquid chromatography and ultraviolet absorbance at 230 nm. Average spike recoveries for samples prepared at 3 spiking levels (25, 50, and 200 g/ton) were 96.3, 92.1, and 88.6%, respectively. The overall method precision at each of the 3 spiking levels was < or = 5.39% relative standard deviation. The limits of detection and quantititation (g/ton formulation) were 3.89 and 13.0 g/ton, respectively.
State of Wisconsin, Wisconsin Department of Agriculture, Trade and Consumer Protection, Bureau of Laboratory Services, 4702 University Ave, PO Box 7883, Madison, WI 53707-7883, USA. matthew.gramse@datcp.state.wi.us
Matthew J
MJ
Gramse
Paul E
PE
Jacobson
D000085:Acetates / Q000737:chemistry; D000097:Acetonitriles / Q000737:chemistry; D000821:Animal Feed / Q000032:analysis*; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002853:Chromatography, Liquid / Q000379:methods*; D010400:Penicillin G / Q000032:analysis*; D012492:Salts / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D013997:Time Factors; D014466:Ultraviolet Rays
D000085:Acetates; D000097:Acetonitriles; D000900:Anti-Bacterial Agents; D012492:Salts; D010400:Penicillin G; C032159:acetonitrile