Development of a simple and rapid HPLC-MS/MS method for quantification of streptomycin in mice and its application to plasma pharmacokinetic studies.

Streptomycin was the first discovered aminoglycoside antibiotic. It has been widely applied in veterinary medicine for the prevention and treatment of bacterial infection. However, the current detection methods are not satisfactory in terms of sensitivity and sample process, which makes them unsuitable for a pharmacokinetic study. A high-performance liquid chromatography-mass spectrometric method employing positive electrospray ionization was developed and validated for the determination of streptomycin concentration in mice plasma. A simple protein precipitation method was utilized to extract streptomycin as well as the internal standard (kanamycin) from mouse plasma. This assay method was validated in terms of specificity, sensitivity, precision, accuracy and recovery. This method was applied to a pharmacokinetic study in mice following intramuscular administration of 200 mg/kg streptomycin. The lower limit of quantification of the developed assay method for streptomycin was 10 ng/mL. The intra-day and inter-day precision was evaluated with the coefficient of variations <14.3%, whereas the mean accuracy ranged from 87.0 to 105.0%. The samples were stable under the experimental conditions. The present method provides a robust, fast and sensitive analytical approach for the quantification of streptomycin in mouse plasma and has been successfully applied to a pharmacokinetic study in mice.