Direct Measurement of Nitric Oxide in Seawater Medium by Fluorometric Method

✍ Scribed by Chun-Ying LIU; Min ZHAO; Chun-Yan REN; Gui-Peng YANG; Pei-Feng LI; Yang HAN

• Book ID: 104452592
• Publisher: Elsevier Science
• Year: 2009
• Tongue: Chinese
• Weight: 354 KB
• Volume: 37
• Category: Article
• ISSN: 1872-2040
• DOI: 10.1016/s1872-2040(08)60136-x

✦ Synopsis

The determination of nitric oxide (NO) concentration in seawater medium by fluorometric method has been investigated, based on the reaction that 2,3-diaminonaphthalene (DAN) has the ability to trap NO to yield the highly fluorescent 2,3-naphthotriazole (NAT). The optimum conditions, such as fluorometric determination conditions ( ex = 383 nm, em = 410 nm), the influence of temperature and equilibrium time on the DAN trapping NO, and the influence of DAN solution on trapping NO, have been examined. The fluorometric intensity is linear with the NO concentration in the range of 1.4-1400 nM with a R 2 of 0.9985 (P < 0.0001). The limit of detection is 1 nM (S/N = 3), the relative standard deviation is 1.63% (NO, 14 nM), and there is no interference from the medium. Compared with fluorescence determination of NO concentration in NaOH medium, this method decreases the limit of detection by one order of magnitude. Combining the purge-and-trap operation, the NO concentration of seawater in Shilaoren of Qingdao (36°05 46 N; 120°29 40 E) was detected to be (0.12 ± 0.01) nM. The method can also be applied to monitor the self-releasing NO change of sodium nitroprusside in seawater.