Reversed Flow Injection Analysis of Nitrate in Drinking Water with UV-induced Reduction to Nitrite and Spectrophotometric Detection
- 海洋环境－已发表论文 
An environmental friendly method was developed based on reversed flow injection (r-FIA) with UV-induced reduction of nitrate to nitrite and spectrophotometric detection. Sample or standard solutions were mixed with a phosphate buffer solution containing diethylenetriaminepentaacetate (DTPA), and then passed through a UV reduction reactor equipped with an 8 W low pressure mercury lamp, where the nitrate was reduced to nitrite. The formed nitrite was detected with spectrophotometric method through Griess reaction. Less than 20 mu mol/L of nitrite showed no effect on the nitrate analysis. Reduction efficiency over 80% was obtained. The detection limit of the proposed method was 0. 053 mu mol/L and linear range was 0. 2-40 mu mol/L. A sample of 20 mu mol/L nitrate was continually measured for 48 times, and a RSD of 2. 22% was obtained. The recoveries of drinking waters were between 90. 9%-100. 6%.