What is a ‘touching’ microscope and how does it ‘feel’ its subject?

8 Aug 2018

Prof Brian Rodriguez. Image: UCD

UCD researcher Prof Brian Rodriguez works with some pretty powerful equipment, much to the chagrin of US Homeland Security.

Behind many great technological breakthroughs are physicists who helped understand how it fundamentally works at an atomic level.

One such researcher is Prof Brian Rodriguez, a lecturer at the School of Physics and Conway Institute of Biomolecular and Biomedical Research at University College Dublin (UCD).

After completing his undergraduate degree, Rodriguez interned at Intel as a manufacturing engineer before moving on to Kobe Steel as a research assistant.

He obtained his master’s and PhD from North Carolina State University and, after completing his postdoctoral appointment at Oak Ridge National Laboratory, he went on to do research at what is now called the Max Planck Institute for Microstructure Physics.

In 2009, he moved to UCD as a lecturer in nanoscience and is now a senior lecturer in the School of Physics and a Conway Fellow at the Conway Institute of Biomolecular and Biomedical Research.

What inspired you to become a researcher?

My parents worked in education and I’ve always been inquisitive. Growing up, I spent a lot of time at the Oregon Museum of Science and Industry and participated in a quite a few of the summer camps it organised.

One specific memory that comes to mind is receiving a pocket microscope from an uncle who was a science teacher. I think this really cemented my interest in science.

In hindsight, it was quite empowering to be able to follow my own curiosity and put whatever I wanted under that microscope. I guess I haven’t changed much, since that’s basically what I do now.

Can you tell us about the research you’re currently working on?

In my group, we are primarily focused on developing scanning probe microscopy techniques and applying these techniques to a broad range of functional materials. This is to understand the properties that underpin the use of the materials in technological and biological applications, and to guide the design and optimisation of the materials.

To do this, we use a special kind of ‘touching’ microscope called an atomic force microscope that can be used to see individual atoms. It operates based on ‘feeling’ the interactions between the atomically sharp probe and the surface of interest, and can be used to provide 3D images of the surface.

We also use this microscope to measure local surface and materials properties, such as electric charge.

During my postdoc at Oak Ridge National Laboratory, under the mentorship of Sergei Kalinin, I was able to demonstrate that measuring nanoscale piezoelectricity in liquid was possible. In fact, it could be advantageous because the long range electrostatic forces could be screened by ions in the solution.

What applications does it have?

At UCD, I followed this recipe again with the help of PhD student Liam Collins – now at Oak Ridge National Laboratory – taking a technique widely used for measuring surface charge and surface potential in air and vacuum, and establishing it in a liquid environment.

Now, we are poised to use these techniques to understand what happens at the surface of a material when placed in solution (the solid-liquid interface). I find this interface incredibly interesting as it governs how cells interact with their surroundings and how the batteries we use in our phones, laptops and electric cars store energy.

I’ve remained fascinated with taking techniques used mainly in air and establishing them in liquid, and this has extended to a 3D bioprinting project with Dr Emmanuel Reynaud of the UCD School of Biomolecular and Biomedical Science.

We have been working, with the support of Enterprise Ireland and Science Foundation Ireland, to print hydrogels directly into a liquid and to use the liquid phase to control the mechanical and biochemical properties of the print.

This is a very exciting area of research. It gives us the opportunity to create complex and much more realistic and predictive prints for tissue engineering, and drug discovery applications.

In your opinion, why is your research important?

While my background has been primarily in fundamental research, through increased understanding and outreach we are moving closer to research that has the potential to impact society in the short term.

Clearly, improvements in energy storage capacity and the longevity and safety of batteries impacts all of us, from improving the battery life of your smartphone to increasing the range of electric cars.

Furthermore, if our 3D bioprinting approach can provide tissue models with better predictive value, it can greatly reduce the cost to bring an effective drug to market.

Are there any common misconceptions about this area of research?

The term atomic force microscopy has caused challenges for some of our colleagues traveling to the US carrying ‘parts for an atomic force microscope’.

While an accurate name for a technique, it is certain to draw the attention of US Homeland Security. We’ve opted for the less suspicious ‘touching’ microscope.

What are some of the areas of research you’d like to see tackled in the years ahead?

Well, as a type 1 diabetic, I’d like to see a cure for that sooner rather than later.

I also love the idea of energy harvesting – using mechanical motion and vibrations or thermal changes or more commonly photovoltaics – to harness energy to power devices.

It could be possible to convert every heartbeat or eye blink or step to energy to power a pacemaker or artificial pancreas and so on.