紫外可见分光光度法测定白菜中硝酸盐含量

[目的]探究紫外分光光度法用于测定蔬菜中硝酸盐的含量是否快捷、方便、准确.[方法]选取日常生活中常见的、代表性较强的白菜为材料,分别放置0、2、4、6、8d,用亚铁氰化钾、乙酸锌、硼酸、活性炭等试剂处理蔬菜匀浆,制得待测液.采用紫外分光光度法测定蔬菜样品待测液中硝酸盐含量,并做加标回收试验,以判断试验准确度.[结果]该方法加标回收率较高,说明准确度较高,RSD小于3.7％,具有较高的精密度.[结论]此方法操作简便、结果准确,适用于蔬菜中硝酸盐含量的测定.

Determination of Nitrate in Vegetables by Ultraviolet Spectrophotometry Method

[Objective] To explore the ultraviolet spectrophotometric method for determination of content of nitrate in vegetables 1s quick,convenient and accurate.[Method] Selecting common and representative vegetables in the daily life as materials,they were placed respectively 0,2,4,6,8 days,potassium ferrocyanide,zinc acetate,boric acid and activated carbon were used to process vegetable homogenate,so as to obtain test liquid.The content of nitrate in vegetables were determined by ultraviolet spectrophotometry,and standard addition recovery experiment was conducted,the accuracy of experiment was determined.[Result] The results showed that the standard addition recovery rate is higher,shows high accuracy,RSD is less than 3.7％,has higher precision.[Conclusion] This method is simple and accurate,and suitable for the determination of nitrate content in vegetables.