Team:Goettingen/Applied Design

Applied Design

Glyphosate is a controversially discussed herbicide, as it might be harmful for the biodiversity and human health. Independently of the glyphosate controversy, we have pursued a scientific approach to develop a glyphosate detection system. The system is cheap and very easy to apply to measure glyphosate in every day samples at home. Any sample, for example food- or soil-derived samples, can be mixed with water. The mixture has to be pressed through a filter into a glass flask, containing dry growth medium, a chromogenic chemical and spores of glyphosate-sensitive and glyphosate-resistant bacteria. The sensitive bacteria can convert the chromogenic chemical to a blue stain. Therefore, if the test sample contains glyphosate, the intensity of the blue color is directly proportional to the glyphosate concentration. To ensure a safe inactivation of the genetically engineered bacteria, ethanol will be filled into the flask right after the detection, killing all bacteria.

In order to create an inexpensive detection method for glyphosate, we constructed a system which can detect the presense of glyphosate in any sample. Moreover, our system is able to determine the concentration of glyphosate. The following figure depicts the function of our measurement system (Figure 1).

Figure 1. Explaning the principle of our product.

Roundup® is sprayed on soil, Then, water is applied to solve the glyphosate from the sample. The solution is filtered through a filter device to avoid any other contaminations like other microorganisms. The sample drops onto solid media powder with all necessary ingredients and Bacillus subtilis spores from the two competing strains. The sample is incubated for 10 h at 37°C with agitation. Now, the blue color can be compared to a test strip. The intensity of the blue color determines the concentration of glyphosate in the sample. The usage of our product is also shown in the following movie.