Microplate assays and on-line analyzer for the spectrofluorimetric determination of carboxylic, thiol and amine compounds – CARBOTHIOLAMINE

The determination of volatile fatty acids (VFA), thiol compounds and amino compounds in environmental or biological samples require pre-treatment of samples (eg extraction) and expensive analytical techniques which not suitable for on-site measurement. However the determination of some of these chemical functions may require their on-site or continuous measurement:
- Determination of VFA is often made necessary in many industrial fermentation processes (wastewater treatment plant, wastewater treatment sludge, landfill sites with energy recovery as biogas,...). The AGV determination is for example important for the efficiency control of anaerobic digestion: anaerobic digestion is inhibited by the presence of large quantities of VFA.
- Determination of thiol compounds but also H2S and sulfides may be interesting on wastewater treatment plants (odor problems, control of biological processes including oxidative stress of bacteria, and corrosion control ), but also in sewers (acute H2S);
- The determination of amino compounds is of particular interest in the field of health (analysis of body fluids), but also in soil microbiology.


In addition, monitoring of these functional groups also has a great interest in the environmental field: support for development of predictive models to study impact of the spreading of sewage sludge, wise use of fertilizers in agriculture, soil phytoremediation ... This set is a tool for decision support for the sustainable management of water quality and soil.


The objective of this project is to enhance the development of a simple, reliable and robust analytical method for the determination of these three functions of ecological, environmental and health importance. A first analytical procedure has been developed and validated, based on a derivation reaction of targeted functions (AGV, amines and thiols) with fluorescent chemical probes for quantification by spectrofluorometric measurement. It is now necessary to complete the validation of this method, to adapt it to the H2S and sulfides compounds and to formalize prototypes, allowing completion of the analytical procedure proposed in two formats: i) ready-to-use microplate kits for laboratory analysis; ii) on-line analyzer for on site monitoring.