2605345 Nitrate Cuvette Test, 0.2 - 30 mg/L NO₃-N

16 mm Test 'N Tube Cuvette test measures 0.2 - 30 mg/L NO₃-N in water and wastewater. The product uses chromotropic acid method (10020). Article 2605345 can be used for 50 tests. TNT product can be evaluated on DR900 only.

Procedure for NO₃-N determination 

Pipet 1mL of sample to Reagent A Test 'N Tube vial, close and invert the vial content 10 times to prepare the blank vial. Put the TNT vial in the colorimeter and push ZERO. Then prepare the sample by adding the content of Reagent B Powder Pillow to the sample vial and inverting the vial content. After 5 minutes, evaluate the sample vial using the aforementioned instrument. Nitrate in the sample enters into reaction with chromotropic acid under strongly acidic conditions to yield yellow product. The recommened measurement wavelength is 410 nm (for spectrophotometers) or 420 nm (for colorimeters). 

Sample preparation

To preserve the water or wastewater sample for up to 24 hours, it is required to store at the temperature between 2 °C and 5 °C. To keep the collected sample for up to 28 days, adjust the sample pH to 2 or less using concentrated sulfuric acid and store at or below 6 °C (43 °F). It is required to adjust the pH to 7 using 5 N sodium hydroxide solution before sample analysis. It is recommended to store the collected sample in glass or polyethylene container. The product storage conditions are between 10 °C and 25 °C.