Case Study

Environmental and Analytical Chemistry Laboratory at Université de Sherbrooke

Professor Segura’s laboratory focuses on the study of emerging environmental contaminants at trace levels. Indeed, more than 100 million compounds are present in the CAS register, however, even more are to be discovered. These compounds present a potential danger to the environment either in their primary form or as transformation products, formed through degradation or metabolic processes. The team of the Environmental and Analytical Chemistry Laboratory then focuses on the identification, monitoring, quantification and the effect of emerging environmental contaminants as well as their transformation products in the environment.

Project Type

The Environmental and Analytical Chemistry Laboratory focuses on the development of quantification methods of trace organic contaminants in multiple environmental matrices: pharmaceutical products in wastewater, monitoring of pharmaceuticals in hospital effluents after advanced oxidation treatment (AOP) such as wet oxidation and pesticides in tissues of vulnerable or endangered species. This laboratory also concentrates on improving LDTD desorption to lower detection limits for the analysis of trace organic contaminants.


Discoveries in the environmental field with the usual tools can be slow and obtaining an accurate assessment of the health of our ecosystems is critical. Furthermore, the analysis of environmental contaminants sometimes requires very low limits of detection.


Objective 1

The first area of ​​research of Professor Segura’s team is the occurrence of environmental contaminants. That is to say, the team seeks to determine which trace contaminants are present in the environment and at what concentrations. Using LDTD technology, Professor Segura's team is able to quantify multiple environmental contaminants in several environmental matrices such as water from ponds, rivers and lakes as well as wastewater.

Objective 2

Subsequently, the second axis of research concerns the fate of environmental contaminants. Indeed, the questions that Professor Segura's team asks are, among others, what are the transformation products of current environmental contaminants and how can we identify them? They can answer many of these questions using high-resolution mass spectrometry. However, LDTD technology can be useful when monitoring the production of transformation products or monitoring the reduction of environmental contaminants following specific treatments.

Objective 3

Finally, the third axis of research of the Environmental and Analytical Chemistry Laboratory of the University of Sherbrooke concerns the evaluation of the toxicity of these environmental contaminants and their transformation products. Professor Segura's team is working on the development of methods of quantification of biomarkers of toxicity that can used to rapidly detect subtle effects on vulnerable or sensitive species such as Daphnia magna.


Aiming to increase the signal of certain analytes in LDTD-QqQMS, the addition of coatings to increase desorption has been studied. Indeed, coatings of chelating agents such as EDTA and NTA and proteins such as IgG and fribrinogene provide signal augmentation for small organic molecules as well as small polar organic molecules with functions of d carboxylic acid, sulfonyl, and nitro respectively.
The use of LDTD technology in tandem with mass spectrometry increases the speed of analysis (compared to traditional mass spectrometry analysis methods, i.e. liquid chromatography and gas chromatography).


The LDTD technology increases the signal by a 10-fold factor with a commercial protein coating for small polar molecules as well as allowing the possibility of analyzing more than 15,000 samples in less than 43 hours and analyzing peptides with LDTD-QqQMS.


More peak area


Samples in 43 hours


Different peptides analyzed


  • Dion-Fortier A., Gravel A., Guérette C., Chevillot F., Blais S., Auger S., Picard P., Segura P. A. (2019) Signal enhancement in laser diode thermal desorption-triple quadrupole mass spectrometry analysis using microwell surface coatings. Journal of Mass Spectrometry 54:167–177,
  • El Yagoubi, Y., Lemieux, B., Segura, P.A., Cabana, H. (2023) Characterization of laccases from Trametes hirsuta in the context of bioremediation of wastewater treatment plant effluent, Enzyme and Microbial Technology, 171, 110308, ISSN 0141-0229,
  • Gravel A., Guérette C., Fortin D., Auger S., Picard P., Segura P. A. (2019) Further studies on the signal enhancement effect in laser diode thermal desorption‐triple quadrupole mass spectrometry using microwell surface coatings. Journal of Mass Spectrometry 54:948-956,
  • Segura, P.A., Guillaumain, C., Eysseric, E., Boudrias, J., Moreau, M., Guérette, C., Clémencin, R., Beaudry, F. (2022) Ultrafast analysis of peptides by laser diode thermal desorption–triple quadrupole mass spectrometry, 36(20):e9373,
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