溶剂萃取-高效液相色谱法分析印楝素乳油中印楝素A含量

Analysis of Azadirachtin EC by Solvent Extraction-HPLC

[目的]建立快速测定印楝素乳油中印楝素A含量的分析方法。[方法]用石油醚萃取杂质,以5 mmol/L乙酸铵水溶液+乙腈(体积比40∶60)为流动相,检测波长为218 nm,采用等质量浓度洗脱的方法进行HPLC-DAD分析。[结果]该方法在5~200 mg/L范围内呈良好的线性关系,相关系数(R^2)大于0.999,最低检出质量浓度(LOD)为0.5 mg/L,定量限(LOQ)为1.3 mg/L,相对标准偏差(RSD)为2.87%,加标回收率为99.53%~102.32%。[结论]该方法分离度高,准确度和精密度好,分析速度快,适合印楝素乳油产品中印楝素A含量分析。

[Aims] This study aims to establish a rapid method for the determination of azadirachtin A in azadirachtin emulsifiable concentrates （azadirachtin EC）. [Methods] The pretreatment of azadirachtin EC samples was carried out by removal of impurities with petroleum ether extraction. Azadirachtin A was quantified by using HPLC coupled with the diode array detection （DAD）. The HPLC separation was performed with the isocratic gradient elution using 5 mmol/L ammonium acetate solution and acetonitrile （40：60, by vol） as the mobile phase. The wavelength for the DAD was 218 nm. [Results] The method showed excellent performance when the calibration curve was linear over the range of 5-200 mg/L with the correlation coefficient R2 〉0.999： The limit of detection （LOD） and the limit of quantitation （LOQ） were 0.5 and 1.3 mg/L, respectively. The relative standard deviation （RSD） was 2.87% and the recovery rate was 99.53-102.32%. [Conclusions] Since the method is simple and quick while showing high resolution, accuracy, and precision, it is thus suitable for the determination of azadirachtin A in azadirachtin EC.