Synthesis
Realisations for this Category
Ferromagnetic nanoparticules targeting the action of cancer-fighting agents
+precise +small +efficient
Structure-property relationships are key to understanding physico-chemical phenomena. On a nanometric scale, one of the challenges relates to the accuracy of the analyses required to determine the exact structure. Prof. Martel’s team, in collaboration of Prof. L’Espérance’s, addressed this problem in the development of a localized therapeutic vector for the treatment of cancer.
The anti-cancer strategy adopted called for combining an anti-cancer agent with ferromagnetic nanoparticles in biodegradable microparticles to target one of the lobes of the liver. The localization involves the use of magnetic resonance imaging (MRI): the movement of microparticles in the blood vessels is therefore controlled by the application of an external magnetic field. The advantage of localization lies in the treatment’s increased effectiveness and reduced side effects.
State-of-the-art equipment and the expertise of Prof. L’Espérance’s team have led to the characterization of sterological and crystallographic parameters of nanoparticles as well as their spatial distribution in microparticles. This data was used to improve the synthesis of nanoparticles and guide the vector in the blood vessels — a major breakthrough in this field.
References
[1] P. Pouponneau, J.-C. Leroux, G. Soulez, L. Gaboury, S. Martel, Biomaterials, 32, 3481-3486 (2011).
[2] P. Pouponneau, J.-C. Leroux, S. Martel, Biomaterials, 30, 6327-6332 (2009).
Researchers
Prof. G. L’Espérance and J.-P. Masse (École Polytechnique), Prof. S. Martel and P. Pouponneau (École Polytechnique)
QNI contribution
Nanoparticles making vaccines more effective
+efficient +effective
Prof. Denis Leclerc has identified nanoparticles produced from the nucleocapsid protein of the papaya mosaic virus (PapMV), which have surprising immunological properties. These nanoparticles can, among other things, enhance the immune response of seasonal flu vaccines.
Studies carried out have shown that these nanoparticles:
- unlike classic adjuvants, not only stimulate the antibody response but cellular response as well;
- can potentially be used in immunotherapy (cancer treatment);
- have no apparent side effects, even in high doses;
- are particularly stable (long-term preservation of vaccines).
The adjuvant will undergo phase 1 testing in humans in 2013.
Reference
[1] C. Savard, A. Guérin, K. Drouin, M. Bolduc, M.E. Laliberté-Gagné , M.C. Dumas, N. Majeau, D. Leclerc, Plos One, 6, e21522 (2011)
Researcher
Prof. D. Leclerc (Université Laval)
Company
Folia Biotech inc.
Project financed by NanoQuébec
Thermoreversible nanoparticles for the controlled release of medication
+effective +precise
A thermoreversible compound is sensitive to temperature. A potential application of this property is the localized released of active ingredients to inflammation sites in the body.
Coming up with an application of this nature presents a sizeable challenge: controlling the structure of these vectors so they offer the properties being sought, notably the temperature for the adequate release of the active agent. The problem lies in the very limited number of polymers, which can be used in the preparation of thermoreversible nanoparticles, making the control of properties difficult.
Professor Claverie’s team has made a great breakthrough with its discovery that, in the form of functionalized nanoparticles, polyethylene — a very common polymer — presents thermoreversible properties. Mastering synthesis process through catalytic polymerization in emulsion makes it possible to control the structure and, therefore, the thermoreversibility of the material, opening the way for concrete therapeutic applications.
Reference
[1] V.A. Kryuchkov, J.-C. Daigle, K.M. Skupov, J.P. Claverie, F.M. Winnick, JACS, 132, 44, 15573-15579 (2010)
Researcher
Pr. J. Claverie (UQAM) and Pr. F. Winnik (Université de Montréal)
QNI contribution
Nanoencapsulation of quantum dots for biomedical imaging
+precise +effective
Quantum dots are semiconducting nanoparticles used in ex-vivo fluorescence biomedical imaging. To consider their in-vivo use, it is necessary to make them more specific (i.e. control their binding to biological ligands) and improve their colloidal stability in order to limit their aggregation.
Prof. Claverie’s group perfected a technique for the encapsulation of lead chalcogenide (PbS) quantum dots by RAFT polymerization (patent pending). The synthesized polymer is grafted to a dispersant, which is itself adsorbed by the quantum dot. The result is 10-20 nm core-shell nanoparticles (inorganic-organic) with very good colloidal stability whose shells can easily be bound to biological ligands. By combining Prof. L’Espérance’s expertise in the field of high-resolution imaging (including high resolution imaging at low dose, high-resolution imaging with negative contrast agent and X-ray spectroscopy) to that of Prof. Claverie, the synthesis of core-shell nanoparticles was demonstrated.
References
[1] J.C. Daigle, J. Claverie, Nanoencapsulation of inorganic particles - US60/972,459 –Filed in Septembre 2007.
[2] J.C. Daigle, J. Claverie, Journal of Nanomaterials, DOI:60918410.1155/2008/609184
[3] P. Das, W.H. Zhong, J. Claverie, Colloid and Polymer Science, 289, 14, 1519-1533 (2011)
Researchers
Prof. G. L’Espérance and J.-P. Masse (École Polytechnique), Prof. J. Claverie (UQAM)
QNI contribution
