Method: colorimetric with color card and comparator block with short test tubes 0.1-0.2-0.3-0.4-0.6-0.8-1.0-1.3-2.0 mg/l NO 0.03-0.06-0.09-0.12-0.18-0.24-0.3-0.4-0.6 mg/l NO-N MQuant^®

The MQuant^® Nitrite test (formally MColortest^®) measures Nitrite that is naturally present in soil, water and food. Nitrite must be closely monitored in drinking and ground water as well as in process, waste, or aquarium water.
The test can be used in:

• Groundwater and surface water, seawater
• Drinking water and mineral water
• Waters from aquaculture
• Boiler and boiler feed water, cooling water
• Wastewater
• Electroplating wastewater
• Food after appropriate sample pretreatment
• Soils after appropriate sample pretreatment

Method
In acidic solution nitrite ions react with sulfanilic acid to form a diazonium salt, which in turn reacts with N-(1-naphthyl)ethylenediamine dihydrochloride to form a red-violet azo dye. The nitrite concentration is measured semiquantitatively by visual comparison of the color of the measurement solution with the color fields of a color card. The unique brilliance of the print and their fine color graduation allow precise analyses, even at the lower end of the concentration range.
Using the refill pack 1.18463 containing all reagents, the original test kit can be used for a very long time, making it a particularly economical and ecological system. 

MCOLORTEST is a registered trademark of Merck KGaA, Darmstadt, Germany

MQUANT is a registered trademark of Merck KGaA, Darmstadt, Germany