非线性建模红外光谱法测定对乙酰氨基酚原料药的含量

Content Determination of Paracetamol by the Nonlinear Quantitative Model with Infrared Spectroscopy

目的:为利用红外光谱法进行对乙酰氨基酚无损检测提供理论依据。方法:准确称取0.002~0.02 g的对乙酰氨基酚原料药,分别加入0.2 g的溴化钾,充分研磨并混合均匀,采用溴化钾压片法配制成待测供试品。光源使用空心阴极灯,扫描频次为30次,分辨率0.5 cm^(-1),扫描范围4 000~400 cm^(-1),测定并记录红外吸收光谱,对药物的特征吸收峰进行筛选,从而确定最佳的特征吸收峰。运用数学建模方法分别建立线性模型和非线性模型。结果:本试验选择用吸光强度较弱但特征性较强的1 016 cm^(-1)吸收峰进行分析。通过建立模型并进行计算可知,非线性模型检测的准确性远高于线性模型检测的准确性,非线性模型方程的r=0.942。结论:非线性建模红外光谱法测定对乙酰氨基酚原料药含量是可行的,其适用于对乙酰氨基酚的无损、快速在线质量控制。

OBJECTIVE： To provide theoretical basis for the detection of paracetamol by infrared spectroscopy. METHODS： 0.002-0.02 g paracetamol was accurately weighed, added into 0.2 g potassium bromide, respectively, fully ground and well mixed, potassium bromide pressing plate method was used for to-be-tested test sample. Using hollow cathode lamp as light, scanning fre- quency was 30 times, resolution was 0.5 cm-1, scan range was 4000-400 cm-1, infrared absorption spectrum was determined and recorded to select the characteristic absorption peaks, then determine the optimized characteristic absorption peaks. Linear and non- linear models were respectively established by using mathematics modeling methods. RESULTS： 1 016 cm-1 absorption peak with weaker absorbance but stronger features was selected for the analysis. According to the model establishing and calculation, the accu- racy of the nonlinear model was much higher than the linear model, r=0.942. CONCLUSIONS： Nonlinear quantitative model for quantitatively determining the content of paracetamol is feasible, and suitable for the on-destructive and rapid on-line quality control of paracetamol.