缓释胶囊中布洛芬含量的核磁共振波谱定量分析方法研究

Study on quantitative analysis method of Ibuprofen content in sustained-release capsules by NMR

目的建立测定布洛芬缓释胶囊中布洛芬含量的核磁共振波谱法。方法以对苯二甲酸单甲酯为内标，将布洛芬溶解在氘代丙酮中，测定核磁共振氢谱，并分别通过内标法和外标法测定其含量。测试温度25℃，脉冲延迟4S，脉冲角45（°），采样点数32768，扫描次数为16次。结果内标法和外标法均能准确定量，内标法平行测定6次，RSD为0．42％，重复性良好；外标法当内标浓度为10mg／mL时，布洛芬在2～20mg／mL的范围内与峰面积具有良好的线性关系，线性方程为y=0．3427x＋0．003，相关系数r=0．9985。结论该方法简便实用、样品用量少、测定结果准确，且可以同时进行结构鉴定，适用于布洛芬的质量控制。

Objective To establish the H NMR method for determining Ibuprofen content in sustained-release capsules. Methods For quantitative determination of Ibuprofen content by ^1H NMR, Mono-methyl terephthalate was used as the internal standard. Both the internal and external standard method were utilized. The conditions were selected as follows： temperature 25℃, relaxation delay time 4 s, pulse angle 45 degree, complex points 32 768, and transient number 16. Results Both the internal and external standard methods could accurately quantify. And the internal standard method had good repeatability, the RSD is 0. 42%. A good linearity was observed in the concentration range of 2-20 mg/mL Ibuprofen （the concentration of internal standard was about 10mg/mL）, with correlative coefficient of 0. 9985. Conclusion This method has good accuracy and repeatability and it can be used for the quality control of Ibuprofen.