The University of Newcastle, Australia

A fascination for physics

Associate Professor Vicki Keast’s enthusiasm for quantum mechanics and electron microscopy has taken her all over the world, and now she’s proud to call the University of Newcastle home.

“I haven’t had a moment of regret. As soon as I moved up here, I saw that it was a supportive, collegiate environment. It’s just a good environment to be around.”

From business to quantum mechanics

After high school, Vicki initially started out on a Bachelor of Business – but quickly realised it wasn’t for her.

“So when I saw that I really need to be doing something else, I decided to go back and do a science degree – expecting I would major in Physics.

“It was my favourite subject in school - but not my best subject.”

But with the support of her colleagues and mentors, including the late Professor David Cockayne – one of the fathers of electron microscopy in Australia – Vicki has excelled in her field.

“I always enjoyed quantum mechanics during my undergraduate studies, so I went to see David [Cockayne] about doing my Honours project on quantum wells. He actually convinced me to do another project (on electron microscopy) which he thought was more interesting! It turns out he was right and I haven’t looked back since.

“Electron microscopy actually involves quantum mechanics. It involves visualising structures at the atomic scale, it involves understanding the way atoms bond together and how that relates to their properties.”

After studying for her PhD at Lehigh University in Pennsylvania, Vicki went on to a post-doctoral position at the University of Cambridge.

Vicki’s current research interests include plasmonic materials and the corrosion of silver nanoparticles. She is a member of the Priority Research Centre for Advanced Fluids and Interfaces.

Looking into nanomaterials

Plasmonic materials are a new type of material built from nanostructured metals. They have unique properties and are able to capture, focus and transmit light in ways that can’t be achieved with conventional materials. They can be used in ultra-sensitive chemical and bio-sensing and can enhance the efficiency of light capture with solar cells.

It’s even been proposed that plasmonic materials could be used in invisibility cloaks and nanoscale circuitry.

Vicki’s research has seen her using high-resolution electron microscopy methods to visualise and understand the way plasmonic materials interact with light. One of her current projects, with PhD student Levi Tegg, involves developing a new group of plasmonic materials, which Vicki hopes will be taken to the point of commercialisation.

“They’re really fabulous materials, with potentially some really interesting applications – infra-red shielding windows, tumour therapy and chemical sensing.”

The mysteries behind antibacterial properties

As for silver nanoparticle corrosion, “You’d think we’d understand it by now but we don’t,” Vicki laughs. Silver nanoparticles are one of the most widely found materials in commercial nano-products, with their main purpose found in antibacterial applications. Antibacterial products are of major significance, as antibiotic resistance is a serious public health problem. As bacteria evolve resistance to everyday-antibiotics, common health complaints can spiral into chronic conditions.

As it stands, there is a significant gap in the knowledge-base between the silver nanoparticles’ antibacterial activity in the laboratory and their real-world effectiveness.

“Our data suggest that there is a common mechanism which lies at the heart of both corrosion and antibacterial activity.”

Vicki is using electron microscopy to study the atomic processes of this corrosion in order to give insight into how silver nanoparticles kill bacteria.

“It will also help us understand how much corrosion occurs even before the product is used. The aim is to inform the design of improved antibacterial products.”