Determination and confirmation of narasin and monensin in chicken, swine, and bovine tissues by LC/MS/MS: Final Action 2011.24.

A multilaboratory study was conducted to validate the reproducibility of AOAC Official Method 2011.24 for determination of narasin and monensin in chicken, swine, and bovine tissues. This study was intended to satisfy requirements for Final Action status through the AOAC Expert Review Panel process. Ten laboratories participated in the study, analyzing blind duplicates of five incurred residue materials for each analyte. After removal of invalid data sets, the method reproducibility (RSDR 12.8-60.6%, HorRat 0.45-1.47) was within AOAC acceptance criteria. The method was awarded Final Action status by the Official Methods Board on October 4, 2012.