Quantification of Amikacin and Kanamycin in Serum Using A Simple and Validated LC–MS/MS Method

BACKGROUND: Amikacin and kanamycin are frequently used in the treatment of multidrug-resistant TB. The current commercially available immunoassay is unable to analyze kanamycin and trough levels of amikacin. The objective was therefore to develop a LC-MS/MS method for the quantification of amikacin and kanamycin in human serum. MATERIALS & METHODS: Using apramycin as internal standard, selectivity, accuracy, precision, recovery, matrix effects and stability were evaluated. RESULTS: The presented LC-MS/MS method meets the recommendations of the US FDA with a low LLOQ of 250 ng/ml for amikacin and 100 ng/ml for kanamycin. No statistical significant difference was found between the LC-MS/MS method and the immunoassay of amikacin (Architect(®) assay, p = 0.501). CONCLUSION: The low LLOQ of amikacin and the ability to analyze kanamycin makes the LC-MS/MS method the preferred method for analyzing these aminoglycosides.