Determination of phenobarbital in neonatal plasma by HPLC-MS/MS method
Objective To establish a method for determination of phenobarbital(PHB)in epileptic neonatal plasma by high performance liquid chromatography-mass spectrometry(HPLC-MS/MS).Methods The samples were pre-treated by precipitation protein method with organic solvent.PHB-D5 was used as isotope internal standards(SIL-IS).Chromatographic column:flow phase:0.05%formic acid-1 mmol·L-1 ammonium acetate-water(A)and methanol(B),gradient elution;flow speed:0.5 mL·min-1.Ion source is electric spray ion source,multireaction monitoring mode for quantitative analysis,using negative ion monitoring mode.The specificity,lower limit of quantitation,standard curve,residual effect,dilution effect,precision,matrix effects,extraction recovery and stability were investigated.Results The linear equation for PHB in plasma samples:y=109.38×10-3x+19.57×10-3(r=0.999 6).The linear range of PHB was 1-75 μg·mL-1,and lower limit of quantitation was 1 μg·mL-1.The intra-day and inter-day precision relative standard deviation was equal or lesser than 5.74%,and the accuracy ranges from 91.29%-103.31%,the recovery ranges from 102.83%-111.22%,with good stability,and this method was not affected by common matrix.Conclusion This study determined the blood concentration of PHB in epileptic neonatal with HPLC-MS/MS,which is rapid,simple,stable,economical,and high specificity.It can be applied to therapeutic drug monitoring of PHB in clinical neanates.
phenobarbitalhigh performance liquid chromatography-mass spectrometryisotope internal standardstherapeutic drug monitoringneonatal