© 2013 Groupe Masson - Université de Montréal Objective: Detection of biomolecules and environmental contaminants Our main objective aims at developing analytical techniques to quantify medically and environmentally important molecules. We are working to perform these measurements directly in the crude samples, without sample clean-up procedures. We employ various analytical chemistry, surface chemistry, nanomaterial characterization and spectroscopic techniques to perform our research. These techniques afford the development and characterization of our novel analytical techniques to measure cancer biomarkers, pathogens, and to detect environmental contaminants. Detection of biomolecules in crude biofluids Researchers involved:  Julien Breault-Turcot, Sandy Shuo Zhao, Alexandra Aubé We specifically aim to detect proteins and biomolecules diagnostic of diseases. We have validated our techniques, in collaboration with Pelletier, based on SPR with the detection of IgG, B-lactamase (elevated levels are indicative of antibiotic resistance) and MMP-3 (a biomarker overexpressed in many cancer). In addition, we are currently developing a rapid test for the detection of methotrexate, an important chemotherapy agent. Drug screening for active ligands to block activity of CD36 receptor constitutes another active research area in our group. We have adapted the SPR instrument for the measurement of dissociation constant of newly synthesized ligands, to establish the ones with the highest affinity for the CD36 receptor. This project involves a collaboration with Lubell in organic chemistry and Ong in pharmacy. Detection of energetic materials in ground and surface water Researchers involved:Nathalia Bukar In this collaborative project with Defense Research and Development Canada, we aim at developing a portable Raman sensor for the detection of energetic materials in ground and surface water nearby army training centers. The analytical protocol we are developing will rapidly assess the presence of energetic materials, to efficiently monitor the environmental impact of military training activities. Plasmonic instrumentation Researchers involved: Maxime Couture, Hugo-Pierre Poirier Richard We are developing various analytical tools based on surface plasmon resonance (SPR) for the detection of biomolecules. In particular, we have built several SPR instruments based on a dove prism. Our version of SPR instrument is compact, portable, inexpensive and high resolution. We are currently working on a multi-channel version of this SPR instrument, to improve the multiplexing capability to analyze several molecules simultaneously. Another version of the SPR instrument we are currently designing should analyze nearly 100 molecules simultaneously. Surface chemistry Researchers involved: Julien Breault-Turcot, Alexandra Aubé Our main objective is to reduce nonspecific adsorption of molecules present in biofluids and to maximize the activity of molecular receptors immobilized on the surface of biosensors. To achieve these objectives, we have synthesized peptide monolayers bearing a thiol group on the N-terminus. We are investigating the nonspecific adsorption of serum on gold surfaces modified with these peptide monolayers. In addition, we are investigating the molecular orientation of peptides on surfaces. The molecules adsorbed on the surface are analyzed with mass spectrometry (in collaboration with Chaurand), in order to better understand the influence of surface chemistry on nonspecific adsorption. We are also investigating with Schmitzer the physico-chemical properties, analyte extraction properties and reactivity of ionic liquid monolayers immobilized to Au surfaces. Various ionic liquids based on imidazolium salts were synthesized with a thiol chain. We investigate the orientation of these monolayers in relation to temperature and various counter-anions. We are also establishing the reactivity and anion echange reactions of surface modified with ionic liquids. Plasmonic materials Researchers involved:  Maxime Couture,Hugo-Pierre Poirier-Richard We are working on the design of novel plasmonic nanomaterials to enhance SPR, fluorescence and SERS responses. The samples we fabricate are based on nanosphere lithography, coupled with plasma etching. We are investigating the plasmonic properties of films over etched nanospheres, and nano- or micro-hole arrays. The optical and analytical properties (LOD, sensitivity reproducibility, etc…) are established for these materials. Scanning probe SPR microscopy Researchers involved: Rita Faid We are currently working on the development of a novel scanning probe technique based on SPR and AFM. This technique aims at measuring the local concentration of chemical messengers secreted by cells. We aim at the development of a technique capable of better understanding the molecular mechanism related to cancer metastasis.