Peter Macdonald

Peter Macdonald

Ph.D. | Professor Emeritus | Chemistry

Research Areas:

Nuclear Magnetic Resonance, Diffusion, Lipid Bilayers, Lipid Bilayer – Polymer Composites

Research Profile:

Macdonald Research
Macdonald’s research laboratory employs nuclear magnetic resonance (NMR) techniques to investigate structure anddynamics in lipid bilayers and lipid bilayer – polymer composites.  Lipid bilayers are the foundational structures of biological membranes and, in addition, play important technological roles in drug delivery systems. Lipid bilayers are intrinsically dynamic, complex assemblies of molecules and these dynamics are intrinsic to their functioning.  NMR provides a unique opportunity to probe such dynamics and our laboratory has developed a number of novel NMR techniques sensitive to diffusion within lipid bilayers, diffusion being one of the key motions undergone by lipids and proteins in biological membranes.  The laboratory is provided with full-time access to high field NMR spectrometers, both solid state and liquid state, capable of conducting virtually any and every NMR experiment.

Currently, the group focuses on two main directions of research. First, we continue the development of NMR methods for measuring diffusion in lipid bilayers, focusing on a novel technique known as CODEX, or “Centre-band Only Detection of Exchange.” Our emphasis now is on extending CODEX to study membrane peptides and their interaction with phospholipids.  Second, we are developing lipid bilayer – polymer composites, wherein a spherical polymer core is encased by a lipid bilayer.  Our goal is to produce novel materials for eventual application as drug delivery vehicles. 

Courses Taught:

JCP221H5, JCP321H5, JCP322H5 (undergraduate), CHM1455H (graduate)

Publications

Recent:

Lai, A., Saleem, Q. and Macdonald P.M. (2015) Centerband-Only-Detection-of-Exchange 31P Nuclear Magnetic Resonance and Phospholipid Lateral Diffusion: Theory, Simulation and Experiment.  Physical Chemistry Chemical Physics, in press.

Saleem, Q, Petretic, A., Zhang, Z., Gradinaru, C.C. and Macdonald, P.M. (2015) Single Lipid Bilayer Deposition on Polymer Surfaces Using Bicelles. Biomacromolecules, 16, 1032-1039.

Morales, H.H, Saleem, Q. and Macdonald, P.M (2014) Thermal Stabilization of Bicelles by a Bile-Salt-Derived Detergent: A Combined 31P and 2H Nuclear Magnetic Resonance Study. Langmuir, 30, 15219-15228.    

Li, M., Morales, H., Katsaras, J., Kucerka, N., Yang, Y., Macdonald, P.M. and Nieh, M.-P. (2013) Morphological Characterization of DMPC/CHAPSO Bicellar Mixtures: A SANS and NMR Study. Langmuir, 29, 15943−15957.

Saleem, Q., Zhang, Z., Gradinaru, C.C. and Macdonald, P.M. (2013) Liposome-Coated Hydrogel Spheres: Delivery Vehicles with Tandem Release from Distinct Compartments. Langmuir, 29, 14603−14612.

Macdonald, P.M., Saleem, Q., Lai, A., Morales, H. (2012) NMR Methods for Measuring Lateral Diffusion. Chemistry and Physics of Lipid, 166, 31-44.

Saleem, Q., Lai, A., Morales, H. and Macdonald, P.M. (2012) Lateral Diffusion of Bilayer Lipids Measured via 31P CODEX NMR. Chemistry and Physics of Lipids, 165, 721-730.

Saleem, Q., Liu, B., Gradinaru, C. C. and Macdonald, P.M. (2011) Lipogels: Single-Lipid-Bilayer-Enclosed Hydrogel Spheres. Biomacromolecules 12:2364-2374.

Nieh, M.-P., Raghunathan, V. A., Pabst, G., Harroun, T., Nagashima, K.J., Morales, H., Katsaras, J. and Macdonald, P.M. (2011) Temperature Driven Annealing of Perforations in Bicellar Model Membranes. Langmuir, 27, 4838-4847.

Macdonald, P.M. and Soong, R. (2011) Diffusion NMR and Bicelle Morphology. Canadian Journal of Chemistry, 89, 1021-1035.