Research Interests: soft materials at the nanosclae, polymers, thin films, dynamics of glassy materials

Research Interests: Soft and living matter at surfaces and interfaces: Polymeric materials, but also C. elegans (a small nematode), bacteria, living cells and soft-colloidal systems.

The main focus of our research group is the study soft and living matter at surfaces and interfaces. The physics of soft materials is distinct from hard matter as the weaker intermolecular bonds result in a large response to external stresses. We study mainly polymeric materials, but also C. elegans (a small nematode), bacteria, living cells and soft-colloidal systems. Understanding material properties at a fundamental level is crucial to the development of new technologies. A surprising aspect of these materials is that on small length scales, like in thin films or coatings, these materials can have properties that differ vastly from those of bulk systems. The differences can be the result of molecules being confined or because the interface plays a greater role in smaller systems.

While retaining significant activity in fundamental studies of polymeric systems on the nano-scale, in recent years our research has also moved into new directions. These include greater efforts at the interface of biology and soft matter, as well as a bourgeoning emphasis on complex fluids beyond polymeric. Current directions of our research in soft and living matter can be summarized under four broad and overlapping areas: 1) Biophysics: micro-swimmers, collective motion, and vesicles. 2) Complex fluids at interfaces: elastocapillarity and soft colloids. 3) Fluids on the micro/nanoscale: nanorheology, confinement, the glass transition. 4) Self assembly and patterning.

The broad range of problems studied in the research team is largely the result of a somewhat opportunistic approach to research. Simply stated, we often stumble upon interesting detours that have resulted in exciting and fun research. Over time some diversions have developed into fully established research directions. Though the projects are diverse, they share a common theme of small length scales, surfaces, and interfaces, with a common physical foundation. The main experimental tools used focus on characterization of surfaces, imaging, and force measurement.

Supervisor Letter:

Dear Prospective Group Member,

We are always looking for new enthusiastic and ambitious researchers to join our team. For details please see our group web page as well as my letter to prospective members

If you are interested in working in our team, please contact me to discuss the possibilities and also feel free to contact any previous members of the group.

Kari

Research Interests: Motions and conformational changes of proteins, transcriptional condensates, morphogen gradients, pore formation in lipid membranes, swimming bacteria, biomineralization.

Experimental Molecular Biophysics

Our focus is the experimental study of the dynamics of single molecules inside biological systems using optical tools as our primary mean of investigation, complemented by simulations and modeling.

Dynamics is essential to the survival of cells and organisms, which are biological units in permanent evolution, and need to process and react to information quickly. Dynamical processes in biological systems happen on a very wide range of length and time-scales, and are governed by complex and intricate rules and mechanisms. In order to unravel the exact mechanisms of processes such as gene transcription and magnetic nanocrystals mineralization, we perform in vivo quantitative measurements at the single molecule level, which have been made possible by recent developments in the domain of fluorescence microscopy.

Check our group website for detailed information on current research projects.

Supervisor Letter:

Cecile Fradin
Department of Physics & Astronomy
McMaster University

Dear prospective trainee,

Students in my group are carrying out experimental research at the frontier between physics and the life sciences. The main focus of our research is dynamics, from single molecule to the swimming motion of bacteria. It involves detecting the motion of molecules and cells both in isolation (single particle detection) and when part of a larger unit (the cell or the embryo), using a range of different biophysical techniques.

Trainees in our group usually have a Physics or Biochemistry background, and we collaborate with groups in Science, Life Science and Engineering. Working as part of an interdisciplinary team is one of the thing I enjoy most about my work.

As a research supervisor I am committed to the education and growth of every trainee in the group, whether your goal is a carrier in academia, in industry or just the opportunity to learn a little bit about Biophysics over the summer. I believe this can be achieved through research projects that are both relevant and well-defined, access to state-of-the-art equipment, close collaborations with researchers in the life sciences, regular meetings between supervisor (me) and trainee (you), a supportive group atmosphere, and the opportunity to attend summer schools and conferences.

Do not hesitate to contact me or anybody else in the group for more information.

Cecile.

Research Interests: Theoretical soft condensed matter physcis, Self-assembly of block copolymers, Statistical mechanics of macromolecules and bilayer membranes

I am interested in theoretical soft condensed matter physics, which is the study of materials such as polymers, liquid crystals, surfactant solutions (micellar solutions and microemulsions), colloidal suspensions (ink, milk, foams, and emulsions), and fluids. The most intriguing property of these materials is their ability to self-assemble into complex organized structures from nanoscopic to macroscopic length scales. Typical examples are micelles (finite aggregates of amphiphiles) and block copolymer microstructures. The past 20 years has seen steady growth in understanding of the physical properties of these complex macromolecular materials. Nonetheless, exciting and challenging problems remain.

In the past years my research has been focused on the statistical mechanics of structures and phase transitions in systems containing polymers, surfactants, and colloids. Examples of my studies include the phases and phase transitions of block copolymer systems, theory of inhomogeneous polymer blends, theory of polyelectrolyte solutions, dynamics of reactive polymeric systems, and theory of polymerization kinetics.

Brief Biography:

• 1982 B.Sc. Physics, Fudan University, China
• 1988 Ph.D. Physics, University of Illinois at Urbana-Champaign, USA
• 1988 Post-Doctoral Fellow/Research Associate, McMaster University, Canada
• 1992 Member of Research Staff, Xerox Research Centre of Canada
• 1999 Associate Professor, McMaster University, Canada
• 2004 Professor, McMaster University, Canada

Supervisor Letter:

Dear Prospective Graduate Student,

My research is in the area of soft condensed matter physics, which is the study of materials such as polymers, liquid crystals, surfactant solutions, colloidal suspensions, and biomaterials. The vast territory of these soft materials extends to plastics, pharmaceuticals, foodstuffs, textiles, proteins, and blood. One of the most intriguing properties of these materials is their ability to self-assemble into complex organized structures. The self-assembly of periodic ordered structures has become the basis for developing new materials and devices, such as photonic band-gap materials, nanoporous membranes, nanowires and high-density information storage. The prediction, design and control of ordered or partially-ordered structures on the nanometer scale has become a central focus of the materials community and is an essential ingredient in the quest for ever more useful and inexpensive devices. Theorists support this endeavor by proposing new types of self-assembled structures and by developing methods of rational design. Furthermore, the self-assembly of soft materials provides a challenging fundamental problem in statistical mechanics.

Recently thermodynamic properties of block copolymer systems have become a paradigm for the study of self-assembly. Block copolymers are macromolecules composed of chemically different blocks tethered together, which spontaneously form a variety of ordered phases with domain sizes in nanometer range (1-100nm). Understanding the structures and phase transitions in block copolymers has been one of the most active research areas in polymer science in the past two decades. My research addresses two key questions, why certain ordered structures appear and how these structures behavior, using a variety of analytical and numerical techniques.

My research group consists of three to four graduate students.  All the members in the group are involved in research topics in theoretical soft condensed matter physics. Collaboration within the group is strongly encouraged, although attention will be paid to the necessity of each student and post-doctoral fellow having their own core research problems. Please contact me for current graduate studies opportunities.

An-Chang Shi

Research Interests: Structure and dynamics of membranes and proteins using X-ray and neutron scattering techniques.

Proteins act like gatekeepers: they control what enters and leaves the cell. “They make sure that good things are transferred through the membrane to feed the cell and bad things stay out,” Rheinstadter explained. “We hope to use this knowledge to enhance or diminish the function of certain proteins.”

Proteins can be a cell’s best friend or worst enemy. Some proteins help defend the cell against disease while others can create holes in the cell membrane, causing the cell to die. Proteins are the first victims of infectious diseases. By understanding how proteins function at the molecular level, scientists can better understand how cells are damaged or die as a result of infectious diseases, which can lead to the development of more effective drugs.

After completing his PhD in condensed matter physics, Rheinstadter became interested in biophysics because he “wanted to do something more relevant,” but as he flipped through the pages of a biophysics textbook, his interest turned to disappointment.

“Everything had been done and discovered,” he said. Looking at the diagrams, he thought, “No one has seen this happen. These mechanisms are so small and the movements are so fast that we can’t look at them with a microscope or magnifying glass. Hardly anything has been seen, measured or quantified. This is what I thought I could do: come up with new, more powerful techniques to observe these fast motions.” He hopes these techniques will someday be used to develop better drugs.

Rheinstadter joined McMaster University in 2009 after completing research and academic appointments in Germany, France and the United States. “It’s a very good school with very positive energy in the department,” he said. “The people are outstanding, very friendly and helpful.”

Supervisor Letter:

Dear Prospective Graduate Student,

One of the major challenges of modern physics is how to contribute to biology and life-sciences including the emerging biotechnology and biomedical device industries, functional foods and nutraceuticals, but also the development of new biomaterials and pharmaceutical developments. There is a huge potential yet to unleash. In our Laboratory for Membrane and Protein Dynamics, we use X-ray and neutron scattering techniques to study molecular structure and dynamics in synthetic and biological tissue. We investigate for instance interaction of common drugs with biological tissue of different composition mimicking brain-like or muscle-like tissue. We also study more fundamental aspects such as motion of lipids and proteins in membranes and formation and properties of nanodomains, so-called rafts. Current projects include developing molecular models for the low-dose aspirin therapy and functioning of common drug enhancers. Our laboratory is equipped with a biophysical preparation facility and operates BLADE (Biological Large Angle Diffraction Experiment), Canada’s most powerful in-house X-ray diffractometer dedicated to membrane research. From the high resolution X-ray diffraction experiments we determine the molecular structure of biological tissue: (1) the out-of-plane structure of the membrane to determine the precise location of the different molecules in the membrane with sub-nanometer resolution and (2) the lateral organization of the different molecular components in the plane of the membrane. You are welcome to explore our research web page if you want to find out more about our research.

As a student in my group you will be trained to work in a biophysical preparation suite and use unique in-house scattering instruments, such as a BLADE. We also use scattering infrastructure at large scale facilities, such as the Canadian Neutron Beam Centre (CNBC) at Chalk River, the Spallation Neutron Source (SNS) in the US, ISIS in the UK and the ILL in France. You will develop excellent organization and teamwork skills to prepare and conduct experiments at these facilities and interact with outstanding scientists. Experiments using the in-house equipment will give you the time to develop your experimental skills.

You will learn to work in a team, however, take the lead in your own research project. The outcome of your work will be published in high impact research journals. This is a very important part of your training and will set the foundation for your future career. You will learn to combine your creativity, your intellect, and hard work to accomplish your discoveries.

You will also have the opportunity to present your work at national and international conferences and workshops such as the Biophysical Meeting and the American Physical Society’s March Meetings, and more specialized neutron and membrane conferences. These experiences will not only build the reputation of the group as a whole, but also your own reputation and training as a young scientist.

If you are interested in joining our team, please contact me at rheinstadter@mcmaster.ca to discuss the possibilities. I will be more than happy to tell you more about potential projects.

I look forward to hearing from you,

Maikel Rheinstadter

Research Interests: The Origin of Life, The RNA World, Protocells, RNA Viruses

Biophysics and Computational Biology

I use computational and theoretical methods to study problems in Biophysics, Molecular Evolution and Origins of Life. Details of my research interests are on my home page.

Supervisor Letter:

Paul Higgs
Department of Physics & Astronomy
McMaster University

Dear Prospective Graduate Student,

I am currently looking for new graduate students. Please check my home page to see the kind of research we are doing. I have students on several different departmental graduate programs – Physics, Biochemistry and Biology. You may like to contact me before applying to discuss which program would be best for you.

You may also be interested in our interdisciplinary graduate program in Astrobiology. This links students with interests in origins of life, evolutionary biology, geochemistry, and astrophysics of planet formation and exoplanets. Students in Astrobiology should apply to one of the departmental programs, selecting the Astrobiology option in the application.

If you would like more information on any of these things, please contact me via the email above.

Paul Higgs.