The science of soft

Imagine the softest surface. Many will imagine pillows, reading socks, or a kitten — but how soft are they?

While you might perceive softness by running your hand across them, you might actually not be able to fully appreciate their velvet nature.

Researchers at the University of Calgary’s Schulich School of Engineering are focusing on the feeling of softness at the nanoscale, which could provide insights into material properties and heterogeneities of soft biomatter like skin tissues, single cancer cells and tumours.

Dr. Seonghwan (Sam) Kim, PhD, is the associate professor in the Department of Mechanical and Manufacturing Engineering and the Tier II Canada Research Chair in Nano Sensing Systems.

“Advances in nanoscience have created opportunities to design, synthesize, fabricate, and manufacture new functional nanomaterials and nanocomposites that have applications in a wide range of fields,” Kim says. “That includes everything from the energy sector to health care to information technology industries.”

He says his research team in the Nano/Micro-Sensors and Sensing Systems (NMSSS) Laboratory is developing novel, nanoscale, multi-modal imaging and characterization techniques and tools that will shed light on the properties of those materials and composites. Kim is hoping to do this through advanced, atomic force microscopy (AFM) techniques.

The smallest of details

Recently published in Communications Physics, findings of a new study by Kim’s team used ultra-light tapping techniques to determine the surface coverage of drug clusters on multi-layered graphene oxide for skin-patch, drug-delivery applications.

“Understanding dynamic, energy-loss mechanisms at the nanoscale is the holy grail of surface physics, surface chemistry, and in identifying cues in mechanobiology,” Dr. Arindam Phani, PhD, a postdoctoral associate in the NMSSS Laboratory, says. “Nature adopts such soft-touch mechanisms in probing its environment, which is abundant in the insect world.”

In this particular research, Phani says the correct estimation of the surface coverage and surface energy of the drug clusters is extremely crucial for optimum drug-release protocol and patch designs.

“We ventured deep into understanding the viscous losses since drug molecules exhibited viscosity owing to their soft-matter properties at the length and time-scales we were probing,” he says. “We also had to simultaneously ascertain the drug coverage density chemically, for which we focused on the dynamics of the AFM tip at contact-enhanced-resonance mode with an infrared beam.”

A mammoth undertaking

Understanding the molecular makeup and heterogeneities of biomaterials, and how they can dictate interaction kinetics, is at the heart of the team’s research. It also opens the door to more collaborative work in different fields.

“We have some very interesting results that connect the cell kinetics to the surface-energy evolution of cancer cells, which we will be communicating soon,” Phani says. “We will also be studying heterogeneities in small proteins to understand their role in folding-kinetics, which we believe will have far-reaching implications and relevance in diseases like Alzheimer’s Disease, Parkinson’s Disease, and even COVID-19.”

Not only will the team be working on the science part of its research, but there’s a commercial perspective as well.

“We will be reaching out to industry leaders in developing and implementing this into a full-fledged AFM, add-on mode with existing systems,” Phani adds.

The team is also working with Innovate Calgary to bring this innovation to market and have recently filed a patent application titled “Transitional Tapping Atomic Force Microscopy for High-Resolution Imaging.”

“Knowledge transition is a very important part of making research accessible to a wider research community,” says Rishi Batra, senior innovation manager at Innovate Calgary. “This innovation has the potential to significantly improve AFM systems for researchers worldwide.”

Read more on the team's findings.

The University of Calgary’s multidisciplinary Engineering Solutions for Health: Biomedical Engineering research strategy drives innovations that are saving lives and revolutionizing health care for Canadians.  With collaborative teams focused on human mobility, health monitoring, advanced biomedical imaging, precision biodiagnostics, regenerative medicine and novel medical technologies, our researchers are transforming quality of life and continuously improving the health system.