Simultaneous Determination of Ethambutol and Isoniazid in Children’s Plasma by UPLC-MS/MS / 中国药房

ABSTRACT

OBJECTIVE:To establish a method for the simultaneous determination of ethambutol(EMB)and isoniazid(INH) in children’s plasma. METHODS:After precipitated with acetonitrile,plasma samples were determined by UPLC-MS/MS method. Using lamivudine as internal standard,Waters ACQUITY? UPLC HSS T3 column was adopted with mobile phase consisted of ace-tonitrile-water(containing 0.05% formic acid and 15 mmol/L ammonium formate)in gradient mode at the flow rate of 0.2 ml/min. By ESI,positive ion detection was conducted in MRM mode. The monitoring transition ion-pair was m/z 205.2→116.0 for EMB, m/z 138.1→121.1 for INH and m/z 230.2→111.9 for internal standard. RESULTS:The linear range of EMB and INH was 10-5 000 ng/ml and 50-5 000 ng/ml,respectively;the limits of quantitation were 10 and 50 ng/ml;RSDs of inter-day and intra-day were all lower than 15% and relative recoveries were 98.7%-105.5%. Plasma concentrations of EMB and INH in 4 children with tuberculo-sis were 94.5-99.7 and 55.1-80.9 ng/ml. CONCLUSIONS:The method is rapid and sensitive,which suitable for children’s plasma concentration monitoring of EMB and INH and pharmacokinetic study.