Nanotechnology (in collaboration with Polytechnique Montreal)

The recent discovery of graphene and its unique structural and physical properties has sparked a surge of interest in implementing this new material in a variety of new devices, targeting applications in ultra-fast electronics, quantum information, carbon-free energy conversion, optoelectronics, and bio-integrated technologies. However, this fascinating material lacks a controlled non-zero bandgap, which prevents its large-scale application in electronic and energy conversion devices. To overcome this limitation, we proposed the direct integration of III-V semiconductors on graphene by exploiting van der Waals epitaxy. Due to their fascinating optical and electronic properties, III-V semiconductors are at the core of numerous technologies including high-efficiency solar cells, lasers, light emitting diodes (LEDs), and ultra-fast transistors, to name a few. Growth of III-V on graphene is an attractive paradigm to develop hybrid systems with novel or enhanced functionalities combining the advantages of these two families of materials within the same platform. Indeed, the development of the proposed hybrid III-V/Graphene structures will create wealth of opportunities to engineer a new class of electronic and optoelectronic devices combining the adventages of both III-V semiconductors and graphene.

This research project seeks to improve our understanding of the van der Waals epitaxial growth mechanism of III-V semiconductors on graphene, which will provide insights to control the properties of such hybrid systems and pave the way to engineering new device structures with potential applications in nano/optoelectronics.

3D bioprinting (in collaboration with McGill University)

Additive manufacturing in the form of 3D printing is now being considered as a bone substitute for the repair of large bone defects [1-4]. 3D printing technology has been used in biomedical studies ranging from external prosthetics, to drug delivery to tissue repair and regeneration with evidence for in vivo compatibility in bone repair [5-7]. In the past few years, the cost of 3D printing hardware has dramatically decreased making it highly accessible. The technology holds promise for fabricating personalized implants that can take the exact shape needed and can mimic the properties of the target tissue. We have successfully used low-cost desktop 3D printers and materials for tissue repair applications in vitro models [8-11]. This project will focus on developing custom material for use in 3D printing/tissue engineering applications. We will generate PLA (polylactic acid) and PCL (polycaprolactone) filaments that contain infusions of either bone mineral (nano-hydroxyapatite) or bioactive glass. The printing parameters and chemical composition of the materials will be characterized. Scaffolds will be 3D printed and tested for stem cell adhesion, viability, growth and bone matrix deposition.


[1] M. Castilho, C. Moseke, A. Ewald, U. Gbureck, J. Groll, I. Pires, J. Tessmar, E. Vorndran, Direct 3D powder printing of biphasic calcium phosphate scaffolds for substitution of complex bone defects, Biofabrication 6(1) (2014) 015006.

[2] J.P. Lichtenberger, P.S. Tatum, S. Gada, M. Wyn, V.B. Ho, P. Liacouras, Using 3D Printing (Additive Manufacturing) to Produce Low-Cost Simulation Models for Medical Training, Mil Med 183(suppl_1) (2018) 73-77.

[3] W. Zhang, Q. Lian, D. Li, K. Wang, D. Hao, W. Bian, J. He, Z. Jin, Cartilage repair and subchondral bone migration using 3D printing osteochondral composites: a one-year-period study in rabbit trochlea, Biomed Res Int 2014 (2014) 746138.

[4] P. Ahangar, M.E. Cooke, M.H. Weber, D.H. Rosenzweig, Current Biomedical Applications of 3D Printing and Additive Manufacturing, Applied Sciences 9(8) (2019) 1713.

[5] S.A. Abbah, C.X. Lam, D.W. Hutmacher, J.C. Goh, H.K. Wong, Biological performance of a polycaprolactone-based scaffold used as fusion cage device in a large animal model of spinal reconstructive surgery, Biomaterials 30(28) (2009) 5086-93.

[6] A. Cipitria, J.C. Reichert, D.R. Epari, S. Saifzadeh, A. Berner, H. Schell, M. Mehta, M.A. Schuetz, G.N. Duda, D.W. Hutmacher, Polycaprolactone scaffold and reduced rhBMP-7 dose for the regeneration of critical-sized defects in sheep tibiae, Biomaterials 34(38) (2013) 9960-8.

[7] M.E. Hoque, W.Y. San, F. Wei, S. Li, M.H. Huang, M. Vert, D.W. Hutmacher, Processing of polycaprolactone and polycaprolactone-based copolymers into 3D scaffolds, and their cellular responses, Tissue Eng Part A 15(10) (2009) 3013-24.

[8] D.H. Rosenzweig, E. Carelli, T. Steffen, P. Jarzem, L. Haglund, 3D-Printed ABS and PLA Scaffolds for Cartilage and Nucleus Pulposus Tissue Regeneration, Int J Mol Sci 16(7) (2015) 15118-35.

[9] P. Ahangar, E. Akoury, A.S. Ramirez Garcia Luna, A. Nour, M.H. Weber, D.H. Rosenzweig, Nanoporous 3D-Printed Scaffolds for Local Doxorubicin Delivery in Bone Metastases Secondary to Prostate Cancer, Materials (Basel) 11(9) (2018).

[10] E. Akoury, M.H. Weber, D.H. Rosenzweig, 3D-Printed Nanoporous Scaffolds Impregnated with Zoledronate for the Treatment of Spinal Bone Metastases, MRS Advances  (2019) 1-7.

[11] R. Fairag, D. Rosenzweig, J.L. Ramirez Garcialuna, M.H. Weber, L. Haglund, 3D-Printed Polylactic Acid (PLA) Scaffolds Promote Bone-like Matrix Deposition In-vitro, ACS Appl Mater Interfaces  (2019).