Projects

Label free high sensitivity detection of bacteria by phages using functionalized optical microcavities

Natural Sciences and Engineering Research Council of Canada (NSERC), Strategic Grant

543’100.00 $ CA          (2008-2011)

We develop novel ultra-sensitive on-chip bacteria sensors based on functionalized optical microcavities by phages. The sensitivity is reached through a thermo-optical effect that produces a shift in the optical resonance of the cavity. Since the cavity has an extremely high quality factor, the detection is therefore highly sensitive. In addition the detection does not require prior labeling of the analyte, reducing significantly the analysis time. The technique allows fast detection of very low concentrations, likely single cells, opening the door to applications where detection time is required to be significantly shorter than the proliferation of the bacteria. The lab-on-chip will be able to identify a wide range of specific bacterial species and strains, e.g. Staphylococcus Aureus, Mycobacterium tuberculosis, Borrelia Burgdorferi (medical applications); Listeria, Salmonella, Staphylococci, Streptococci (food safety); E-coli, Clostridium, Anthrax (water and environment); and Legionella Pneumophilia (cooling systems).

Collaborators: Profs. Y.-A. Peter (PI), L. J. Dubé (Université Laval), J. L. Nadeau (McGill)

Collaborations: MPB Communications Inc., AvidBiotics Corp.

 

A New Class of Optical Microcavities -- inhomogeneous dielectric resonators --

Subvention de projets de recherche en équipe, Fonds québécois de la recherche sur la nature et les technologies (FQRNT)

181 ’244.00 $ CA          (2007-2010)

[Available in French only] Les microcavités optiques sont des structures diélectriques qui permettent le stockage de puissance optique dans des volumes de quelques micromètres à des fréquences de résonnance spécifiques. Ce phénomène a des applications en optique (petites tailles de faisceau laser pour lecture/écriture des CD/DVD), télécommunication (transmission laser à longue distance), et dans les senseurs bio-chimiques (protéines et eau lourde). La puissance optique est principalement située sur les bords de la cavité, ce qui rend le dispositif très sensible à son environnement et par conséquent en fait un senseur très intéressant. Par analogie avec les modes acoustiques, les modes propres des résonateurs diélectriques bidimensionnels sont de type "whispering gallery". Ces modes sont caractérisés par un grand confinement de la lumière près de la frontière de la cavité et permettent donc un bon couplage avec l'extérieur. Chaque mode propre est caractérisé par sa longueur d'onde, son facteur de qualité et sa directionnalité imposée en partie par la symétrie spatiale du système. Les études effectuées jusqu'à présent montrent l'effet d'un certain nombre de paramètres sur ces caractéristiques, à savoir: la forme et la taille de la cavité, l'indice de réfraction ainsi que la différence d'indice avec l'extérieur. Le contrôle de ces paramètres et la compréhension de leur influence sur les caractéristiques d’émission sont à la base de ce projet. Notre but est la réalisation d’applications de ces microcavités dans le domaine des senseurs bio-chimiques, des modulateurs compacts, des coupleurs accordables ou des dispositifs optiques non-linéaires.

Collaborateurs: Profs. Y.-A. Peter (PI), L. J. Dubé (Université Laval)

 

Enhanced Optical Multianalyte Detection Lab on Chip for Point-of-Care Diagnostic

Natural Sciences and Engineering Research Council of Canada (NSERC), Strategic Grant

515’000.00 $ CA          (2006-2010)

We develop novel ultra-sensitive tunable photonic crystals (PhCs) that are used at specific optical resonances to detect bio-labeled quantum dots (QDs). It is envisioned that the sensitivity enhancement will be such that the time consuming DNA extraction and PCR amplification steps usually needed prior to the analysis might be eliminated. This will of course lead to a drastic reduction of the analysis time. In addition, in contrast to conventional fluorophores, QDs that have extremely narrow emission spectra, allow to move beyond single parameter biochemical paradigms towards routine multianalyte detection schemes. This aspect is of central importance, since biochemical reactions do not exist or operate in isolation, and every reaction is dependent on many other reactions through the principles of biochemical networks, reaction kinetics, and equilibria. Today, spectral data are collected with discrete optics, or are dispersed onto an array for detection, whereas our approach based on bio-labeled QDs, which emission is selectively enhanced by the tunable photonic crystal. The latter will be integrated on a lab-on-chip aimed for point of care diagnostics (POTC), with on-board microfluidics enabling the handling of extremely small volumes of analytes, in particular the accurate delivery of solutions containing QDs.
The lab-on-chip will be able to measure the relevant biochemical parameters, and provide the information base to better understand and effectively treat infectious diseases in shorter time. The implementation of these new technologies in a POTC that can be produced at relatively low cost will represent a significant reduction in wait times, treatment delays and eventually more effective and efficient treatment for afflicted patients. By eliminating the need for costly laboratory testing for initial diagnosis, this new technology will also provide significant cost savings to health-care providers.

Collaborators: Profs. Y.-A. Peter (PI), M. Skorobogatiy, O. Guenat, J. L. Nadeau (McGill)

Collaborations: Nanometrix, Altairnano

 

Tunable Micro Electro Mechanical Grating in Silicon for Optical Systems and Devices

Natural Sciences and Engineering Research Council of Canada (NSERC), Collaborative Research and Development Grant

90’000.00 $ CA            (2006-2009)

The goal of the project is to fabricate devices made of vertical silicon walls of micrometric size, compatible with optical fibers and thus adapted to the optical telecommunication and sensor networks. The basic element of these devices is a silicon wall manufactured by micromachining techniques. A number of useful components are designed by combing several walls together having specific thicknesses as well as those of the air gaps in between. Spectral mirrors, filters and sensors are among the relevant applications of such gratings. The components are compact (whatever functionality, only four silicon walls are in general sufficient to obtain the targeted response) and they are deformable by means of applied electric voltages. The project includes manufacturing of such Micro Electro Mechanical Systems (MEMS), tests and demonstration of prototypes. As
an example application, we build a tunable fiber laser using such a grating.

Collaborators: Profs. Y.-A. Peter (PI), N. Godbout, S. Lacroix, M. Skorobogatiy, R. Kashyap

Collaborations: MPB Communications Inc.