Quantitation of spectinomycin residues in bovine tissues by ion-exchange high-performance liquid chromatography with post-column derivatization and confirmation by reversed-phase high-performance liquid chromatography-atmospheric pressure chemical ionization tandem mass spectrometry.
Determinative and confirmatory methods of analysis for spectinomycin residue in bovine kidney, liver, muscle and fat have been developed. The determinative method is a single-column HPLC ion-exchange procedure that incorporates a two-step post-column oxidation of the secondary amines to primary amines followed by derivatization with o-phthalaldehyde. The method was validated in all tissues to a low-end concentration of 0.10 micrograms/g (limit of quantitation) and to a high-end of 10 micrograms/g for kidney, which is the rate-limiting tissue for residues of spectinomycin. The recovery of spectinomycin from all tissues was > 80% and the variability (R.S.D.) was generally < 10%. For liver, an alternative reversed-phase HPLC separation was required for incurred-residue samples. The confirmatory method employed an atmospheric pressure chemical ionization-MS-MS approach utilizing a rapid reversed-phase HPLC system with a mobile phase of methanol and 1% acetic acid. The protonated molecular ion for spectinomycin at m/z 333 produced four diagnostic reaction-product ions at 98, 116, 158 and 189 for confirmation. The method was validated to a lower limit of confirmation of 0.10 micrograms/g.
Hornish
R E
RE
Pharmacia and Upjohn Worldwide Animal Health, Kalamazoo, MI 49001, USA.
Wiest
J R
JR
D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D007202:Indicators and Reagents; D013058:Mass Spectrometry; D008460:Meat / Q000032:analysis*; D012996:Solutions; D000198:Spectinomycin / Q000032:analysis*
D007202:Indicators and Reagents; D012996:Solutions; D000198:Spectinomycin