DPMB prize awarded to Suzie Dufour during the 2010 ACP congress for the best oral presentation by a student (third prize).

Title : Spatial resolution of optical fibre micro-probe and their use in vivo.

Abstract: Optical micro-probes made from tapered optical fibres can be used in vivo as fluorescent sensors to detect labelled cells or to measure their activity using functional dyes such as calcium indicators. In the configuration we proposed [1, 2], the same tapered fibre is used to carry the excitation light into the tissue and to collect the fluorescence originating from the sample.

To better analyse the results obtained with these probes, we calculated and measured their spatial resolution (detection volume). Knowing the detection volume of the probe is important to evaluate the probability of recording from one cell or the capacity to resolve adjacent cells. A numerical simulation (performed with Matlab) was used to evaluate the impact of the excitation profile (gaussian or homogeneous), the probe numerical aperture, the index profile of the fibre, the probe diameter, and the excitation and collection wavelength on the spatial resolution. The spatial resolution was also measured using small fluorescent micro- spheres (2 μm) for different probe diameters. A 488 nm solid state laser was used for excitation. The micro-spheres were moved in front of the probe tip in a controlled fashion, and the collected fluorescence was measured for each position of the micro-sphere, which allowed us to obtain the axial and traversal resolution. When comparing the estimated and measured resolutions for a given probe we found that they were comparable. Finally, we present examples of fluorescent cell detection, in fixed tissue and in living animals.
Funded by CIHR and NSERC. S.D. and Y.L. are supported by Studentships from the CIHR Neurophysics Training Program.

2010 CIPI Young Photonics Innovator Award (prix du jeune innovateur en photonique de l'ICIP 2010) à Stéphane Pagès et Sophie Laffray

Description of the innovation: We developed a non invasive strategy to adapt high resolution functional optical imaging to moving CNS structures with subcellular spatial resolution at millisecond time scales in living animals. The Image Plane Locking system (IPL) is a fast adaptive non-contacting device to compensate for movement (up to 100 mm) within very short time (< 10 ms). The device operation is based on a continuous optical monitoring of the position of the tissue and a feedback system to control the position of the objective. This maintains constant the distance between the tissue and the objective. The IPL allows for compensation of rapid movements (e.g. breathing and pulsations) and locking of the plane of interest in focus. This new in vivo functional imaging approach allows millisecond resolution in moving tissue with minimal invasiveness, and provides a powerful tool to study network activity.

Funded by CIHR and NSERC. S.P. and S.L. are supported by Studentships from the CIHR Neurophysics Training Program.

CRULRG researchers obtain a major grant from NSERC

A group of 11 canadian researchers, amongst them Drs Paul and Yves De Koninck as well as Daniel Côté from CRULRG will share a major grant obtained from the CREATE program (a training program oriented towards novelty, collaboration, and research experience) of NSERC. This 1.65 M$ grant over 6 years will be used to support the graduated studies programs in biophotonics put in place in 2008 at Laval University.

A new graduate program (M.Sc. and Ph.D. levels) in Biophotonics just opened at Université Laval. The Neurophysics group was significantly involved in the creation of this program which will start in Fall 2008. Paul De Koninck is the director of the program in Biophotonics while Mario Méthot will take charge of the coordination aspect. More information about the graduate program in Biophotonics.

The Neurophysics group co-organized the 1^st Franco-Canadian Symposium on Neurophotonics in collaboration with the University of Bordeaux. The first edition took place on October 20th-23rd, 2008 in Bordeaux. The "New Frontiers in Neurophotonics" will alternatively take place in Bordeaux and Quebec City. More information about the meeting is available here.

Frontiers in Neurophotonics 2008 took place on May 18-24, 2008 at the CRULRG in Quebec City. This international summer school on advanced cell imaging techniques was a success and a great opportunity to meet our invited experts, and learn and discuss the latest advances in live cell imaging techniques. More about the summer school here.

As part of our expansion, the Neurophotonics Center, an 11,500 sq. ft. surface has been recently renovated, thanks to the financial support of the Ministry of Economic and Regional Development and Research . The new facilities provide state-of-the-art laboratories and clean rooms for our experts in the fields of photonics and neuroscience. We are always looking for outstanding graduate students and post-doctoral fellows for our expanding groups. More information available here.