Simultaneous determination of nitrate and nitrite in rainwater by HPLC with electrochemical detector

• Published in: BUNSEKI KAGAKU Vol. 35; no. 11; pp. 944 - 946
• Main Authors: KOYANAKA, Seiko, IMANARI, Toshio, KOSHIISHI, Ichiro, TOGAWA, Tadayasu, ISHIGAMI, Akiko
• Format: Journal Article
• Language: Japanese
• Published: The Japan Society for Analytical Chemistry 05.11.1986
• Subjects: copper-cadmium reduction; electrochemical detector; HPLC; nitrate; nitrite; rainwater
• ISSN: 0525-1931
• DOI: 10.2116/bunsekikagaku.35.11_944

A method for the simultaneous determination of nitrate and nitrite was studied by HPLC with an electrochemical detector (ECD). Nitrate and nitrite were separated by TSK gel QAE-2SW (150mm×4mm i.d.) and nitrate was reduced to nitrite on a copper-cadmium column (100mm×5mm i.d.). Nitrite was detected by ECD with a glassy carbon electrode as a working electrode, the potential of which was set at+0.9V vs. Ag/AgCl. The mobile phase consisting of 0.1M phosphate buffer containing 0.05M sodium chloride (pH 7.0) was pumped at a flow rate of 0.5ml/min.Injection volume was 20μl. According to this method, the retention times of nitrate and nitrite were 8.0 and 9.8min, respectively. Calibration curves for both anions were linear in the range of 0.240ng as N and relative standard deviation (n=5) were less than 2%. We applied this method to the determination of nitrate and nitrite in rainwater.