4456369 Nitrate ISA Reagent Powder Pillows, 0.1-100.0 mg/L NO₃-N

Reagent Powder Pillows measure 0.1-100.0 mg/L NO₃-N in water and wastewater. The product uses direct ion selective electrode method (8214). Each package can be used to perform analysis of 100 samples.

Before you start take into account the following:

• Prepare, condition and calibrate the probe before analysis.
• In order to condition the probe, put it in 100mL of the lowest concentration standard solution for 1 hour.

Procedure for NO₃-N determination

Mix 25 mL of sample and Nitrate ISA Powder Pillow in the beaker. Stir the beaker content, rinse the probe with deionized water and dry using lint-free cloth. Put the probe in the solution and select READ. To perform calibration procedure, push CALIBRATE and READ, evaluate the remaining standard solutions, and press DONE and STORE.

Summary of method

The absorbed nitrate ions cause potential that is proportional to the nitrate concentration. The ISE membrane is nitrate ion-exchanger in inert PVC plastic matrix. The nitrate electrode has internal silver/silver chloride element that results in fixed-reference potential when it touches the internal filling solution.

Sample preparation

To preserve the water and wastewater sample for later analysis, it is required to adjust the sample pH to 2 and store at the temperature below 6 °C (43 °F) for up to 28 days. It is not recommended to use mercury compounds as preservatives.