差示分光光度法测定血清苯巴比妥浓度

Determination of phenobarbital in serum by differential spectrophotometry

目的:改进差示分光光度法测定血清苯巴比妥浓度。方法:以二氯甲烷在酸性条件下二次提取,用苯巴比妥在不同pH值的介质中吸收度之差值,按差示分光光度法测定血清中苯巴比妥浓度。结果:5～20μg·ml-1与25～100μg·ml-1的苯巴比妥标准溶液之间稳定性差异呈显著性(P<0.01)。血清苯巴比妥浓度回收线性范围5～140μg·ml-1;回收率(101.2±2.7)%;日内变异(2.51±0.23)%,日间变异(2.70±0.25)%。结论:本法线性范围宽,回收率高。

OBJECTIVE:To improve differential spectrophotometry for the determination of phenobarbital concentration in serum.METHODS:Phenobarbital was extracted two times with dichloromethane under acidic conditions.The standard curve of phenobarbital in serum was established according to the absorbance deviations of phenobarbital in different pH media,and the phenobarbital in serum was determined by differntial spectrophotometry.RESULTS:The stability of phenobarbital standard solution of 5～20 μg·ml -1 showed significant difference from that of 25～100 μg·ml -1 ( P < 0.01 ).The linear range of phenobarbital in serum was 5～140 μg·ml -1 ,the mean recovery was ( 101.2 ± 2.7 )%,and the variations of inter day and intra day were ( 2.51 ± 0.23 )% and ( 2.70 ± 0.25 )%,respectively.CONCLUSIONS:The method has a wide linear range and high recovery, could be applied to monitor phenobarbital in serum in small or medium hospitals.