~1H核磁共振法测定三氯生的纯度

Purity Determination of Triclosan by Proton-Nuclear Magnetic Resonance

以丙烯酰胺为内标,氘代二甲基亚砜(DMSO-d6)为溶剂,对用1 H核磁共振法测定三氯生纯度条件进行试验。在脉冲延迟时间20s和扫描次数64等条件下得到1 H-NMR谱图。选择H-11(δ6.88)和δ5.59分别作为样品和内标的定量峰,取其积分峰面积平均值按公式计算三氯生的纯度。结果表明:样品与内标物的质量比在1.01~10.16内,与其定量峰面积比值呈线性关系。平行测定同一样品6份,按所得样品对内标物定量峰面积的比值,计算其相对标准偏差(n=6)为0.12%。按所提出方法分析了三氯生实样,结果的平均值(n=3)为99.78%,与质量平衡法所得结果(99.81%)相符。

A study on the application of 1H-NMR spectroscopy to the determination of purity of triclosan （TCS）, by using acrylamide as internal standard and DMSO-d6 as solvent, was made, and the 1 H-NMR spectrum was obtained under the conditions of time of pulse delay of 20 s and scanning time of 64. H-11 （δ 6. 88） and δ 5.59 were selected as the quantitative peaks for the sample and the internal standard. Averages of integrals of the peak areas were taken and used for calculation of purity of TCS by the formula given. As shown by the result, linear relationship was obtained between values of mass ratios of sample （mτ） to internal standard （ms） ranged between 1.01 and 10. 16 and respective values of ratios of integrals of peak areas of sample （Ar） to internal standard （As）. Six portions of a same TCS sample were taken and analyzed by 1 H-NMR in parallel, values of ratios of peak areas of samples to internal standard were taken, and value of RSD （n=6） found was 0. 12%. A TCS sample was analyzed by the proposed method for its purity, and average value of the results （n= 3） found was 99.78%, which was in consistency with the results found by mass balance method （99.81%）.