离子色谱法同时测定黄芩饮片中亚硝酸盐和硝酸盐含量

Simultaneous Determination of Nitrite and Nitrate in Scutellaria Baicalensis with Ion Chromatography

目的：建立黄芩饮片中亚硝酸盐和硝酸盐的测定方法。方法：样品采用超声辅助提取,经C18小柱净化,离心过滤后直接进样。色谱柱为Ion Pac AS23 4 mm×250 mm离子交换柱,淋洗液浓度为4.6 mmol/L Na2CO3·H2O和0.2 mmol/L Na HCO3,流速为0.8 m L/min,使用配有电导检测器的ICS-1000离子色谱仪测定亚硝酸根和硝酸根离子。结果：亚硝酸根和硝酸根离子分别在0.02~4.00、0.2~40.0μg/m L内线性关系良好,相关系数为0.99978、0.99995,平均回收率为94.46%、103.98%,方法的精密度和重复性良好。结论：该法具有检测时间短、偶然误差小、灵敏度高、操作简便等优点,适于大批黄芩样品的检测。

Objective：To establish a method to determine nitrite and nitrate in Scutellaria baicalensis. Methods：Ultrapure water was used for ultrasound-assisted solvent condition,extracting solution was purified by C18 column and extract liquor directly inject after the centrifugaled and filtrated membranes.Ion Pac AS23 4 mm×250 mm inorganic anion exchange chromatography column,4.6 mmol/L Na2CO3·H2O and 0.2 mmol/L Na HCO3 as the isocratic eluant at a flow rate of 0.8 m L/min. ICS-1000 ion chromatograph equipped with a conductivity detector were adapted to assay nitrite and nitrate. Results：The Linear relationship of nitrite and nitrate were good respectively in linearity of 0.02~2.00 μg/m L and 0.2~20.0 μg/m L,correlation coefficient were 0.99978 and 0.99995,average recovery were 94.46% and 103.98%,The precision of the instrument and the repeatability of method were good. Conclusion：The method has many advantages such as short detection time,accidental error is small,high sensitivity,simple operation,etc.suitable for testing a large number of Scutellaria baicalensis samples.