ABSTRACT
OBJECTIVE To establish a UPLC-MS/MS method for the determination of plasma concentration of three carbapenem antibiotics， i.e. ertapenem （ETP）， imipenem （IPM） and meropenem （MEM）. METHODS After protein precipitation with methanol， the plasma samples were separated by ACQUITY UPLC BEH C18 column （2.1 mm×50 mm， 1.7 μm） using stable isotopes of three antibiotics （ETP-D4， IPM-D4， MEM-D6） as the internal standard. The mobile phases were 98% acetonitrile +2% water +0.1% formic acid and 98% water +2% acetonitrile +0.1% formic acid， by gradient elution. The flow rate was 0.3 mL/min and the column temperature was 40 ℃. Scanning analysis was performed in the positive ion and multiple reaction monitoring mode. RESULTS The method had good specificity， good linearity （r2≥0.993） in the range of 0.2-200， 0.1-100 and 0.1-100 μg/mL of ETP， IPM and MEM， and good intra-batch and inter-batch precision and accuracy （all RE≤5.14%， all RSD≤11.15%）， the matrix effect and extraction recovery were consistent （RSD≤12.99%）. CONCLUSIONS This study establishes the UPLC-MS/MS method to simultaneously quantify the plasma concentration of ETP， IPM and MEM. The method has the advantages of simple pretreatment， short detection time and small sample quantity to meet clinical requirement.