The Pearce team at Michigan Technological University developed an open source alternative to assessment of nitrate concentration
The Enzymatic Nitrate Analysis Method is a green sustainable method, which is safe for the user and the environment.
The enzyme catalyzes the reduction of nitrate to nitrite in the presence of NADH, and replaces the toxic heavy metal cadmium or other toxic reagents used for this reaction. In both these methods, the nitrite produced from the reduction of nitrate and any nitrite in the sample reacts with the Griess reagents to produce a magenta color with absorbance at 540 nm. Thus, these methods report the nitrate plus nitrite content of a sample.
For the nitrate reductase method, it is easy to determine the nitrite content of a sample by simply omitting the enzyme from the reaction and directly reacting with the Griess reagents to obtain absorbance at 540 nm.
Free and open source hardware (FOSH) and software (FOSS) design methodologies have
been proven to be useful for radically reducing the cost of scientific equipment while maintaining
accuracy and precision.
Case and cuvette holder are fabricated by 3D printing
Cost of instrument approximately 64 $ (without manpower) .
Paper reference : PLOS ONE | DOI:10.1371/journal.pone.0134989 August 5, 2015 8 /