核磁共振内标法测定维生素C片中维生素C的含量

目的:建立核磁共振测定维生素C片中维生素C含量的方法。方法:采用Varian unity Inova600MHz核磁共振仪,溶剂为氘代二甲亚砜,内标为苯,测定温度为21℃,观察频率为599.951MHz,谱宽为9599.2Hz,脉冲宽度为11.65μs,采样时间为2s,延迟时间为5s,采样次数为32次,在此条件下采集样品1H-NMR谱。结果:供试片中维生素C含量为40.1%,RSD=1.38%,平均回收率为100.9%。结论:核磁共振内标法测定维生素C片中维生素C的含量,方法简便、准确,可用于维生素C的定量分析。

Quantitative Determination of Vitamin C in Vitamin C Tablets by Proton Nuclear Magnetic Resonance with Internal Standard Method

OBJECTIVE： To establish nuclear magnetic resonance （NMR） method for content determination of vitamin C in Vitamin C tablets. METHODS： 1H-NMR spectra were obtained with a Varian unity Inova 600 MHz spectrometer at 21 ℃. For each sample, 32 times of scans were recorded with the following parameters： observation frequency of 599.951 MHz, spectra width of 9 599.2 Hz, puleses width of 11.65 μs, sampling time of 2 s, delayed time of 5 s. Vitamin C was mixed with benzene as internal standard in DMSO. RESULTS： The average content of vitamin C and RSD were 40.1% and 1.38%. The average recovery was 100.9%. CONCLUSION： The method is simple and accurate for quantitative analysis of vitamin C.