傅里叶变换红外光谱法测定食品添加剂二氧化碳中的二氧化氮

Determination of nitrogen dioxide in food additive carbon dioxide by fourier transform infrared spectroscopy

建立了基于傅里叶变换红外光谱法测定食品添加剂二氧化碳中的二氧化氮。给出了最佳进样条件,确定了二氧化氮与二氧化碳的特征吸收峰,选择对二氧化氮定量分析的特征峰位置为2950~2850 cm^-1。采用重量法配制了系列浓度标准气体,结果表明,样品浓度在(10~100)×10^-6 mol/mol范围内与吸收峰面积呈良好的线性关系,相关系数为0.99991,检出限为0.00125×10^-6 mol/mol。平行样品测定结果的相对标准偏差为0.51%~2.48%,平均回收率为98.4%~101%,测量不确定度为2.7%。该分析方法简便快捷、测量结果准确可靠,对食品添加剂二氧化碳中二氧化氮定量分析有重要意义。

A method for the determination of nitrogen dioxide in food based on Fourier transform infrared spectroscopy was established.The optimal injection conditions were given,and the characteristic absorption peaks of nitrogen dioxide and carbon dioxide were determined.The position of characteristic peak for quantitative analysis of nitrogen dioxide was 2950-2850 cm^-1.A series of concentration standard gases were prepared by gravimetric method.The results showed that there was a good linear relationship between the sample concentration and the absorption peak area in the range of(10-100)×10^-6 mol/mol,the correlation coefficient was 0.99991,and the detection limit was 0.00125×10^-6 mol/mol.The relative standard deviations of the parallel samples were 0.51%-2.48%,and the average recoveries were 98.4%-101%,and the measurement uncertainty was 2.7%.The method is simple,rapid,accurate and reliable.It is of great significance for the quantitative analysis of nitrogen dioxide in food additive carbon dioxide.