Isotope dilution HPLC-MS/MS method for simultaneous determination of four antimicrobials in children with small volume of plasma
Objective To establish a high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method for simultaneous determination of meropenem,linezolid,voriconazole and posaconazole in children with small volume of plasma,and to use the method in children therapeutic drug monitoring(TDM).Methods The plasma samples were precipitated protein by methanol.And then,the analytes were gradient eluted on an EVO-C18 column by HPLC-MS/MS with mobile phase consisted of water(0.1%formic acid)-acetonitrile(0.1%formic acid)at the flow rate of 0.5 mL·min 1.Ions were monitored in the multiple reaction monitoring(MRM)mode,using positive ion electrospray ionization(ESI).Results Meropenem had a good liner relationship in 0.5-64.0 μg·mL-1(r=0.999 2),0.2-25.6 μg·mL-1 for linezolid and voriconazole(r=0.999 2,r=0.999 9),and 0.1-12.8 μg·mL-1 for posaconazole(r=0.998 9).Accuracy,precision,matrix effect and stability studies all met the requirements.This method was fully verified,and applied to determine the plasma antimicrobial concentrations of 49 pediatric patients.Conclusion The method is simple,rapid,sensitive and suitable for children's plasma concentration monitoring of four antimicrobials.
meropenemlinezolidvoriconazoleposaconazolehigh performance liquid chromatography-tandem mass spectrometrytherapeutic drug monitoringchildren