Determination of nitric oxide in natural seawater by Nafion modified electrode

The nitric oxide in the medium of natural seawater was determined by a platinum electrode modified with Nafion. The optimum conditions such as' enriching time, modifying time and the thickness of modifying film have been examined. The peak height is linear with concentration of NO in the range of 1.0-77 mu mol/L with a r of 0.9916. The detection limit is 0.4 mu mol/L; the relative standard deviation is 0.5%. The enriching mechanism of nitric oxide by Nafion was also discussed. This method was also validated by S-nitroso-N-acetyl-D,L-penicillamine decomposing.