离子色谱法测定蔬菜中的硝酸盐、亚硝酸盐、磷酸盐及总磷、总氮

以白菜为例建立超声辅助提取(UAE)离子色谱法(IC)测定蔬菜中硝酸盐、亚硝酸盐、磷酸盐、总氮、总磷含量的方法，并对白菜各部位的硝酸盐、亚硝酸盐及磷酸盐含量的分布进行研究。结果表明：当进样量为20μL，使用Na2CO3-NaHCO3 为淋洗液，NO2 － 、NO3 － 、PO43－、总氮(TN)、总磷(TP)的最小检出限分别为0.015、0.014、0.030、0.014、0.061mg/L，相关系数为0.9990～0.9999，RSD 为0.22%～0.94%，回收率为80.0%～110.0%。该法简便快速、精密度和准确度高，15min 就可完成白菜中硝酸盐与亚硝盐、磷酸盐含量的分析。

Determination of Nitrate,Nitrite, Phosphate,Total Phosphorus and Total Nitrogen in Vegetables Using Ion Chromatography

Chinese cabbage was used as the sample to establish a method for determining nitrate, nitrite, phosphate, total phosphorus (TP) and total nitrogen (TN) through ultrasound-assisted extraction and ion chromatography (UAE-IC). The distribution of these compounds in different parts of Chinese cabbage was also investigated. The detection limits for nitrate, nitrite, phosphate, TP and TN were 0.015, 0.014, 0.030, 0.014 mg/L and 0.061 mg/L, respectively, at a sample injection volume of 20 μL using an elution system composed of Na2CO3 and NaHCO3. The determination coefficients of the developed linear equations of these analytes and the precision relative standard deviations (RSDs) were in the range of 0.9990 to 0.9999 and 0.22% to 0.94%. The spike recovery rates of these analytes were between 80.0% and 110.0%. This method is characteristic of simple operation, fast detection, and accurate and reliable results.