The GB/T 23278.8-2009 standard specifies the determination method of nitrate in sodium stannate, which is suitable for the determination range of 0.020% to 0.60% nitrate. In the method, after the analysis of the sample with water, it is neutralized with dilute sulfuric acid and filtrated to separate the nitrate from tin (IV). In the pH 4~ 5 aluminum sulfate-silver sulfate-Boricacid-sulfamic acid medium, the nitrate content is determined by ion meter or pH/mV measurement using liquid film nitrate ion electrode. The reagents include tertiary distillation water, stannous sulfate, sodiumhydrate solution, etc., as well as aluminum sulfate-silver sulfate Boricacid solution and sulfamic acid solution. The standard solution needs to be prepared precisely to ensure the accuracy of the test results.