Caldur® Nitrite – Photometric
Nitrite determination in the water using a photometer (0.02-1.0 mg/l NO₂-)
Private customers can also find our range in our partner store Ampha-Analyse.
Reagent for Caldur® Nitrite – Photometric:
See also:
CALDUR® Nitrite Test Set – Photometric
What is nitrite measured for?
Nitrite (NO₂-) is an intermediate product of biological nitrogen conversion and an Reagent for fresh impurities in water. The drinking water limit value is 0.5 mg/l NO₂- (Drinking Water Ordinance), and 0.1 mg/l at the waterworks outlet.
Nitrite is harmful to health as it impairs the blood’s ability to transport oxygen (methaemoglobinaemia). It poses a particular risk to infants and small children. In new pipes, nitrite can temporarily reach elevated levels due to bacterial activity.
Nitrite is the most dangerous nitrogen parameter in aquariums and must be checked regularly. In sewage treatment plants, nitrite control is used to monitor nitrification.
How does the test set work?
The CALDUR® Nitrite Test Set – Photometric is based on the NED method (naphthylethylenediamine). After adding a reagent to the water sample, a pink coloration develops within 5 minutes, the concentration of which is precisely determined with the WINLAB Data Line photometer.
Advantages of the CALDUR® test set
- Sensitive measuring range 0.02 – 1.0 mg/l NO₂-
Detects contamination far below the drinking water limit
- 200 provisions per set
Cost-efficient for continuous use
- High precision due to photometric evaluation
Objective, reproducible measurement results with the WINLAB Data Line
- Proven NED method
Highly selective for nitrite
Areas of application
Carrying out the measurement:
- Fill the round cuvette with sample up to the 10 ml mark
- Add 5 drops of reagent A and mix
- Wait for 5 minutes reaction time
- Insert the cuvette into the WINLAB Data Line photometer
- Start measurement – result is displayed directly in mg/l NO₂-
Tip for best results
The sample should be measured as fresh as possible, as nitrite is unstable and can quickly oxidize to nitrate. Store the sample in a cool place and protect it from direct sunlight.
Important notes
- Adhere exactly to the response time of 5 minutes
- Avoid direct sunlight during the measurement
- Wipe the cuvette with a lint-free cloth before measuring
- Thoroughly rinse the test tube with the sample before each measurement
- Measure sample as soon as possible after collection
- Requires WINLAB Data Line photometer (Art. 37-000100)
Measuring range
| Property | Value |
|---|---|
| Measuring range | 0.02 to 1.0 mg/l NO₂- |
| Resolution | 0.01 mg/l |
| Method | NED method, photometric evaluation |
In contrast to the colorimetric method (color chart), the photometer provides exact numerical values with a higher resolution. Intermediate values are calculated automatically – ideal for documentation and quality assurance.
Number of possible destinations
With a CALDUR® Nitrite Photometric test kit you can carry out 200 measurements.
This refers to the quantity of reagents contained.
Measuring accuracy and reproducibility
Resolution: 0.01 mg/l
Reproducibility: Very good if the application instructions are followed
Interference: Strongly oxidizing substances such as chlorine (> 2 mg/l) can influence the result. Heavily colored or true samples can interfere with the measurement.
What to do if measured values are out of range?
Measured value > 1.0 mg/l
| Verduction | Execution | Calculation of the measured value |
|---|---|---|
| 1:1 | 5 ml sample + 5 ml nitrite-free water | Measured value × 2 |
| 1:4 | 2 ml sample + 8 ml nitrite-free water | Measured value × 5 |
Measured value < 0.02 mg/l
Measured value is below the detection limit. For more sensitive measurements, please contact our technical support.
Specifications at a glance
| Property | Value |
|---|---|
| Parameters | Nitrite (NO₂-) |
| Item number | 31-073352 |
| Method | Photometric (NED) |
| Measuring principle | Photometric evaluation with WINLAB Data Line |
| Measuring range | 0.02 to 1.0 mg/l NO₂- |
| Resolution | 0.01 mg/l |
| Duration of analysis | 5 minutes |
| Number of provisions | 200 |
| Number of reagents | 1 |
| Packaging | Plastic bag |
| Scope of delivery |
|---|
| 1 reagent bottle (reagent A) with detailed labeling |
| 1 round cuvette (10 ml) |
| Detailed operating instructions (DE/EN) |
| Safety data sheets for all reagents |
| Resealable plastic bag |
Reagent details
| Reagent | Volume | Shelf life | Notes |
|---|---|---|---|
| Reagent A (NED) | 30 ml | 24 months (24M) | NED reagent, shake before use |
Shelf life: The shelf life starts from the date of manufacture (printed on the bottle).
After opening, the reagents should be used within 12 months.
Store the test kit in a dry, cool place (10-25°C) and protected from direct sunlight.
Required accessories
The photometer is not included in the test set and is available separately.
Additional information
| Packaging | Plastic bag, Refill pack |
|---|
Flyer
Operating instructions
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