title: Simultaneous determination of avermectins in bovine tissues by LC-MS/MS.
abstract: Analytical method for the simultaneous quantification of avermectins (AVMs), abamectin B1a, abamectin 8,9-Z isomer B1a, emamectine benzoate B1a, emamectine benzoate 8,9-Z isomer B1a, ivermectin, eprinomectin B1a, doramectin and moxidectin in bovine tissues (muscle, liver and fat) was developed by LC-MS/MS in electrospray positive ion mode. The separation was achieved on a short TSK-GEL ODS 100V column with the mobile phase consisting of acetonitrile and aquatic 0.1 mM ammonium formate containing 0.1% formic acid v/v at a flow rate of 0.2 mL/min with gradient elution. Liquid-liquid extraction with isooctane was used for the sample extraction/preparation of analytes in bovine samples. The linearity of the calibration curves was excellent in matrix-matched standards, and yielded the coefficients (r(2)=0.997-0.999, range from LOQ to 500, 1000 or 5000 ng/g) of determination of the target analytes. Recoveries were in the range of 87.9-99.8% with associated precision values (within-day: 1.5-7.4%, n=6, and between-day: 1.5-8.4% for 3 days) for repeatability and reproducibility. LC-MS/MS method has been proven to be highly efficient and suitable for the simultaneous determinations of eight AVMs in bovine tissue samples.
authors.affiliation: Department of Physical and Analytical Chemistry, School of Pharmacy, Kinjo Gakuin University, Moriyama-ku, Nagoya, Japan. kinoue@kinjo-u.ac.jp
authors.forename: Koichi
authors.initials: K
authors.lastname: Inoue
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Yoshimi
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Hino
authors.forename: Hisao
authors.initials: H
authors.lastname: Oka
mesh_terms: D000818:Animals; D002138:Calibration; D002417:Cattle; D002850:Chromatography, Gel / Q000379:methods*; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000032:analysis; D057230:Limit of Detection; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D007559:Ivermectin; C019264:avermectin