A rapid and simple UPLC method for serum vancomycin determination in pediatric patients undergoing continuous infusion or intermittent infusion of vancomycin.

Vancomycin is a glycopeptide antibiotic widely used against Gram-positive bacteria such as methicillin-resistant Staphylococcus aureus and coagulase-negative Staphylococcus. Several studies have found that in adults, continuous infusions of vancomycin showed earlier attainment of desired target drug concentrations and reduced nephrotoxicity relative to intermittent infusion. In the pediatric population, there is no consensus on the best vancomycin infusion method. The present study developed and validated a simple and cost-effective UPLC method to determine serum vancomycin levels in pediatric patients and applied it to the therapeutic drug monitoring of vancomycin in children who were treated with either continuous infusion or intermittent infusion of vancomycin. The sample preparation procedure involves only protein precipitation and filtration, and the UPLC method takes 5 min/sample. The assay was linear from 5 mg/L to 100 mg/L (R2 = 0.999). The precision and accuracy were determined at 4 concentration levels. The intraday variability (%CV) ranged from 1.23% to 6.01% (n = 6), and the interday variability ranged from 3.02% to 9.75% (n = 18). The accuracies were good and ranged from 91.21% to 112.63%. Serum vancomycin was stable at room temperature for 12 h or for 3 freeze/thaw cycles, and the processed sample was stable in an autosampler within 15.5 h.