John R. Dutcher

John Dutcher

Professor, Canada Research Chair in Soft Matter & Biological Physics and Director Nanoscience

Contact Information

Telephone: 519-824-4120 x53950

Email: dutcher@uoguelph.ca

Office: MacN 451

Online: PSI Group

Education

  • B.Sc. (co-op) in Engineering-Physics, Dalhousie University, 1983
  • M.Sc. in Condensed Matter Physics, University of British Columbia, 1985
  • Ph.D. in Condensed Matter Physics, Simon Fraser University, 1989

Professional Experience

  • NSERC Postdoctoral Fellow, Optical Sciences Center, University of Arizona, 1988 - 1990
  • Assistant Professor, Department of Physics, University of Guelph, 1990 - 1995
  • Associate Professor, Department of Physics, University of Guelph, 1995 - 1999
  • Professor, Department of Physics, University of Guelph, 1999 - present

Honours & Awards

  • Governor General’s Gold Medal, Dalhousie University, 1983
  • NSERC Postgraduate Scholarships, University of British Columbia and Simon Fraser University, 1983 - 1988
  • NSERC Postdoctoral Fellowship, Optical Sciences Center, University of Arizona, Nov 1988 - Aug 1990
  • Premier’s Research Excellence Award, Province of Ontario, 1999
  • Presidential Distinguished Professor Award, University of Guelph, 2000
  • Tier I (Senior) Canada Research Chair in Soft Matter Physics and Biological, University of Guelph, 2006 – present
  • Fellow of the American Physical Society, 2007

Highlights Of Professional Activities

University of Guelph

  • Director, Centre for Food and Soft Materials Science, University of Guelph, 1999 – present
  • Director, B.Sc. Nanoscience Program, University of Guelph, 2010 - present

National

  • Theme Leader, Advanced Foods & Materials Network, national Network of Centres of Excellence, 2003 - 2009
  • Member, Research Management Committee, Advanced Foods & Materials Network, 2003 - 2010
  • Director of Academic Affairs, Canadian Association of Physicists, 2009 - 2012
  • Chair of CAP-NSERC Liaison Committee, Canadian Association of Physicists, 2009 - 2014
  • Member and Chair (2007-08), Condensed Matter Physics Grant Selection Committee, NSERC, 2005 - 2008

International

  • Special Advisory Editor, Journal of Polymer Science Part B: Polymer Physics, 2010 – present
  • Editor, Journal of Polymer Science Part B: Polymer Physics, 2008 – 2010
  • Member, Editorial Advisory Board, Soft Matter Journal, 2008 – present
  • Member, Editorial Advisory Board, Colloids and Surfaces B: Biointerfaces, 2010 – present
  • Member, Editorial Board, Scientific Reports, 2014 - present
  • Member, Editorial Advisory Board, Journal of Polymer Science Part B: Polymer Physics, 2002 - 2008

Industry

  • Founder, Mirexus Biotechnologies; Chief Science Officer and Board Member, 2015-2016; Chairman of the Board, 2013-2015; Interim CEO, 2010-2013 (Mirexus is commercializing a polysaccharide nanoparticle technology discovered in the Dutcher Lab)
  • Consulting: DuPont Performance Coatings, Nexia Biotechnologies, Dow Chemical Company

Professional Societies

  • Member of American Physical Society, Canadian Association of Physicists, Materials Research Society, Biophysical Society, American Society for Microbiology, Canadian Society of Chemistry, Biophysical Society of Canada

Research Activities

KEYWORDS: Nanobiomaterials; physics of soft materials, surfaces and interfaces; polymers and biopolymers at the nanoscale; polymer physics; viscoelasticity; bacterial biophysics; biopolymer nanoparticles; thin film instabilities; self-assembly and pattern formation

In the Dutcher Lab, we study soft matter and biological materials at surfaces. This is particularly challenging because the structure of these materials is hierarchical, with different types of structure at different length scales, and there is a correspondingly large range of response times for the materials. The materials are “soft” because the intermolecular interactions are comparable to thermal energies, which means that small changes in their environment, e.g. temperature, pH, external fields, can produce large changes in their properties. This can be exploited to achieve a deep understanding of the subtle interplay between the different interactions that lead to the observed properties. This research also leads naturally to the discovery of new and unique biomaterials, which can be exploited in new technological applications.

Specifically, our research focuses on developing a fundamental understanding and predictive power for the physical properties of polymers, biopolymers and bacterial cells at surfaces and in thin films. We apply a broad range of surface-sensitive experimental techniques and our fundamental, physics-based strategies to develop simple models of these complex soft matter systems. We focus our approach on a wide variety of questions such as: What are the effects of an interface and changes in the environment on the conformation of biopolymers? What are the structure and mechanical properties of naturally occurring, nanostructured biomaterials? How do bacteria stick to surfaces? What is the effectiveness and mechanism of action of novel antimicrobial compounds? How do enzymes break down cellulose so that cellulosic ethanol can be made more efficiently? The answers to these questions lead to improvements in understanding as well as new applications and technologies.

We have chosen to focus on three areas in which we can make a major international impact: (1) physical properties of bacteria, bacterial adhesion, and bacterial biofilms; (2) proteins and peptides at surfaces; and (3) novel polysaccharide nanoparticles for use in industrial and biomedical applications.

  1. We use state-of-the-art techniques such as atomic force microscopy (AFM) and surface-sensitive fluorescence techniques to measure the physical properties of bacteria at surfaces. This work has direct implications for the development of novel antimicrobial compounds, and the prevention of the formation of bacterial biofilms on surfaces. Highlights of this work include the development of a novel AFM-based approach to probe the time-dependent mechanical properties of single bacterial cells; the characterization of collective motion of bacterial cells as they “twitch” on surfaces; and the isolation, purification and characterization of nanostructured biomaterials obtained from bacterial cells and their biofilms, such as the peptidoglycan sacculus (outer bag) of the bacterial cell, and very fine protein filaments called Type IV pili.
  2. Our efforts in biomaterials discovery have led to the discovery of novel polysaccharide nanoparticles that are isolated and purified from sweet corn. The particles have many applications in the personal care, food and nutrition, and biomedical industries. These applications rely on exceptional properties that emerge from the structure of the nanoparticles and their interaction with water, such as a remarkable capacity to retain water, and low viscosity and exceptional stability in aqueous dispersions. The uniform surface properties of the particles make them ideal for chemical functionalization, which further broadens their uses. The technology is being commercialized by our spin-off company, Mirexus Biotechnologies Inc. (www.mirexusbiotech.com).
  3. We look at the molecular level to study proteins and peptides at surfaces. In one of our projects, we study the underlying mechanisms of how enzymes break down cellulose using AFM and surface plasmon resonance imaging techniques. We have worked closely in this project with Iogen, an Ottawa company who is a world leader in cellulosic ethanol, taking straw from farmers and converting it into ethanol. In another project, we are using single molecule force spectroscopy to demonstrate the effect of nanoscale surface curvature on the adsorption of proteins and protein-protein interactions.