Technical study of determination of NO2- , NO3-in food by ion chromatography sing conductivity and ultraviolet detector coupled with Metrohm Inline Dialysis
OU Yang-yun, Rong Xiao-wen Xu Xiao-bo
Guiyang Center for Disease Prevention and Control,Hunan,424400 China
Abstract：Objective To establish the method of determination of NO2- , NO3- in food which were purified by Metrohm Inline Dialysis after Ultrasonic extraction using conductivity and ultraviolet detector.Method Food samples were extracted by ultrasound .After 30 minutes, massive samples were filtered by quantitative filter paper. 10ml upper filtrate were discarded and middle filtrate were injected in Metrosep A Supp 7-250/4.0 anion exchange column with 3.8 mmol/L Na2CO3 eluent solution at 0.8 mL /min.The temperature and pressure of 0 anion exchange column were 45℃ and 11.0 Mpa. Suppression-conductivity detection was used to determinate NO2- , NO3- in food samples .For high salt samples, UV-VIS detector was used for determination of NO2- in samples at 215nm wavelength.Result The analysis of NO2- , NO3- using conductivity detection was finished within 36 minutes under the chromatographic condition presented above. Calibration curve obtained by conductivity detection showed good linearity with r=0.9998 (NO2-) andr= 0.9999(NO3- )(from 0.05mg/L to 0.5 mg/L). Calibration curve obtained by UV-VIS detection showed good linearity r= 0.9999(from 0.05mg/L to 0.5 mg/L). The presicion (RSD,n=7) of these two detections was ranging from 1.75% to 2.30%. The recoveries were ranging from 94.8% to 107.4%. The limits of NO2- , NO3- detecting by conductivity detector were 0.0092 mg/kg and 0.017mg/kg respectively. The limit of NO2- detecting by UV-VIS detector was 0.0126 mg/kg.Conclusion The method can apply to the determination of NO2- , NO3- in food samples with different salt content.
欧阳云, 容晓文, 徐晓波, 谭建华, 宁红卫. 英蓝渗析离子色谱电导--紫外联用法测定食品中亚硝酸根,硝酸根的方法学研究[J]. 实用预防医学, 2016, 23(2): 223-225.
OU Yang-yun, Rong Xiao-wen Xu Xiao-bo. Technical study of determination of NO2- , NO3-in food by ion chromatography sing conductivity and ultraviolet detector coupled with Metrohm Inline Dialysis. , 2016, 23(2): 223-225.
2016, Vol. 23 
