Determination of the Concentration of Gabapentin in Human Plasma by LC-MS/MS / 中国药房

ABSTRACT

OBJECTIVE:To establish a method for the concentration determination of gabapentin (GBP) in human plasma.METHODS:After precipitated by methanol,using sulfamethoxazole as intemal standard,LC-MS/MS method was adopted.The determination was performed on Diamonsil C18 column with mobile phase consisted of water (containing 0.05％ formic acid)-methanol using a gradient elution program at the flow rate of 1 mL/min.The column temperature was 30 ℃,and sample size was 20 μL.The ESI was equipped and quantitative analysis was operated in positive ion and MRM mode.The mass transition ion-pairs were followed as m/z 172.0→154.1(GBP) and m/z 279.0→124.0 (internal standard).RESULTS:The linear range of GBP was 13.4-10 720.4 ng/mL (r=0.992 3,n=5).The limit of quantitation was 13.4 ng/mL,and the minimum detection limit was 4.0 ng/mL.RSDs of inter-day and intra-day were all lower than 10％.Relative errors ranged-4.93％-5.10％.The recoveries ranged 86.2％-90.3％ (RSD＜5％,n=6),and matrix effects ranged 87.6％-92.1％.The plasma concentration of GBP in 10 epileptic patients ranged 2 075.19-4 078.87 ng/mL (n=20).CONCLUSIONS:The method is proved to be sensitive,specific,practical and suitable for plasma concentration monitoring and pharmacokinetic study of GBP in epileptic patients.