Kolorimetrische Bestimmung von Nitrat: Das Boxometer – Photometrie to go.

Summary Colorimetric determination of nitrate with a detection method adapted to field conditions and portable, digital measuring devices. A highly sensitive method for the determination of nitrate in lentic waters in the field has been established. The nitrate detection works analogous to the color reaction known from the Grieß reagent. The procedure has been modified in a way that it can be carried out on site on the water body under field conditions. For this purpose, a measuring device has also been developed that allows simple colorimetric evaluation. This so‐called "boxometer" consists of two mobile phones and a few everyday items and can be easily rebuilt by everyone. The colorimetric analysis is carried out using the RGB system of digital devices in an epi‐illumination setting, which allows a sensitive investigation of the absorption of the samples within narrow limits. This method can also be used in many ways in teaching or where colorimetric measurements should be carried out but no spectrophotometer is available. [ABSTRACT FROM AUTHOR]