Simple operation process of nitrate nitrogen reagent

Author: 同奥科技

Abstract: 本文介绍了水样中硝酸盐氮浓度测试的操作流程。首先，根据预测的浓度范围选择适当的操作步骤：0-20 mg/L内直接测定，超出20 mg/L需稀释后测试，结果乘以稀释倍数。在操作过程中，通过水样颜色变化（棕黄色）判断浓度，避免交叉污染，使用合适的移液工具，并定期校准移液枪以确保准确性。同时，针对硝酸盐氮试剂的使用，建议在频繁测试时对试剂进行稀释，但需注意其保质期较短。

Concentration prediction:Before testing the water sample, the nitrate nitrogen value of the water sample should be predicted, and it should be diluted and measured after exceeding the range. Example: Predicting nitrate nitrogen concentrationsThe value is 0-20mg/L, and the operation step of the 0-20mg/L range needs to be selected; To predict nitrate nitrogen concentrations above 20 mg/L, water is requiredThe sample concentration is diluted to 0-20mg/L and then measured, multiplied by the dilution factor.

Notes:[3.2mL (10+1) sulfuric acid + 0.8mL nitrate nitrogen reagent (2)], it is generally recommended to use separate amounts; If the test frequency is high,Nitrate nitrogen reagent (2) can also be diluted 5 times with (10+1) sulfuric acid for later use, and 4mL can be directly added to the test tube when used (Note:The 5-fold diluted mixture has a short shelf life, so use it as soon as possible after dilution, consult the manufacturer or sales representative for details. ）

1. When the predicted value is in the range of 0 - 20mg/L

If nitrate nitrogen is present, the water sample will appear brownish-yellow, and the darker the water sample, the higher the concentration value. Analytical Procedure: Nitrate nitrogen ; Watch out for overrange tips!

The simple operation process of nitrate nitrogen reagent is shown in Figure 1

2. When the predicted value exceeds 20 mg/L

The water sample needs to be diluted to the above concentration value range, and then the operation is carried out according to the corresponding range, and the measurement result is multiplied by the dilution factor.

3. Hands-on test steps

The simple operation process of nitrate nitrogen reagent is shown in Figure 2

4. Precautions

◆ If nitrate nitrogen is present, the water sample shows brownish yellow, and the darker the color, the higher the concentration value of the water sample.

◆ Pay attention to cross-contamination, use different measuring utensils for different liquids (pay attention to changing the tip when using a pipette).

◆ Use appropriate pipetting tools to take liquids, and large volume measuring tools cannot measure small volumes of water samples, such as: 20mL pipettes cannot be used to remove 2mL and belowFor liquids up to 2mL, 2 pipettes with a 1mL pipette are recommended.

◆ When using a pipette, it is necessary to calibrate the pipette frequently (it is recommended to do so once a week), and pay attention to replacing the tip during use.