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The scientists at UCD’s Nanoscale Function Group have access to six world-class atomic force microscopes (AFMs), incredibly powerful microscopes capable of imaging objects as small as single atoms. (For more background on AFMs, read this recent post and check out this online AFM tutorial.)    

Every day these scientists see stunning images of our world on the nanoscale, where the surfaces of tiny pieces of metal look like huge mountain ranges and the detail in biological components just a few atoms thick can be seen.

Let’s take a look at some recent images from the UCD lab.

 

This image of the residue left behind by ivy glue shows an area just 25 micrometers x 25 micrometers in size. A micrometer is one millionth of a metre.

Earlier this year, researchers at the University of Tennessee used an AFM to reveal that ivy plants secrete a glue that contains uniform nanoparticles 70 nanometres across to achieve their incredible gripping abilities. The team is currently investigating what makes the nanoparticles stick to surfaces and hope to develop a paint that can protect walls from damage by climbing ivy.

Lipid bilayers are composed of two layers of fat cells organised in sheets. At just 5 nanometers (nm) thick, these minute structures form a layer that allow only water and gases to pass through cell membranes. This image shows the surface of a lipid bilayer that’s 5 nm x 5nm in size. A nanometre is one biollionth of a metre, approximately the size of a single carbon nanotube.

Dr. Khizar Sheikh, a Senior Research Fellow in UCD is using AFM technology to study lipid bilayers. “This is the only instrument that can look at lipid bilayers in their natural environment,” says Sheikh.

See more incredible AFM images after the turn.

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This image shows an area of rat stem cell just 50 micrometres x 50 micrometers in size. Stem cells have the ability to become various types of cell, such as a brain cell, muscle cell or blood cell, making them one of the nature’s most versatile biological components.

In 2003, scientists at the Shea Lab for Cellular and Tissue Engineering at the University of Illinois, Chicago succeeded in growing a full-size copy of a human jaw joint complete with bone and cartilage by coaxing rat stem cells to multiply into a human jaw structure. Projects like these are helping to create a new era of designer replacement body parts.

In April, it was reported that the Pentagon is planning a US$250 million research collaboration with universities and hospitals to discover how to help wounded soldiers regenerate skin, muscle and limbs from their own stem cells. Their plan is to harvest adult stem cells before a soldier goes into the battle and then use them to regrow new limbs within days if that soldier gets wounded. U.S. Army scientists have already reconstructed one Marine’s ear using his own stem cells.

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UCD researchers are gaining a reputation as cutting-edge developers of AFMs. The team hacked an existing AFM to  incorporate a laser diode like those used for noise reduction in commercial CD and DVD players.

The diode was used to detect the motion of the AFM’s cantilever as it scanned the surface of the sample, and considerably improved the quality and resolution of the resulting image.

“This had never been used in an AFM before. This was the world’s first system like this to be completely built from the ground up,” says Jarvis.  

“Two of our AFMs are microscopes that we built ourselves and the other instruments have been modified in some way to maximise their potential. That’s why we have people come from all over the world to use our microscopes,” says Jarvis.  

The UCD lab even attracts students from the United States, because of the really high resolution its AFMs achieve.

“We’ve got a student from Cambridge with us at the moment who is here because he can’t do this kind of work at Cambridge. He was in the office first thing this morning telling us that the equipment works great. We like that,” says Jarvis.

Design features developed by the UCD team also feature in the new Cypher AFM (shown here), manufactured by US-based Asylum Research. The Cypher AFM is the world’s first completely new small sample AFM/SPM in over a decade and is one of the highest resolution AFMs in the world. 

Jarvis’ lab has had a long running collaboration with Asylum Research through which AFM designs and technologies are traded back and forth.

“We have students going back and forth all the time to the States to work on the system,” says Jarvis.  

As part of that collaboration, Jarvis’ lab is receiving a brand-new Cypher AFM sometime in the next few weeks.

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This 90 micrometre x 90 micrometre image of a live stem cell shows the cell’s underlying cytoskeleton. Cytoskeletons are flexible, acting as both muscle and skeletons and are responsible for cell movement, cytokinesis, and the organization of tiny components called organelles inside cells.

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Amyloids are insoluble protein fibres associated with a wide range of diseases, including Alzheimer’s disease, Huntington’s disease and Type 2 diabetes.

This image shows a tiny amyloid fibril 11 nm in diameter that’s wrapped in a layer of smaller protofilaments, like strands of rope. 

Dr. Mads Bruun Hovgaard, a Danish Postdoctoral fellow is using UCD’s AFM lab to study the structure of amyloids.

“You can’t get AFMs like these in Denmark,” says Hovgaard. “It’s a real step up in terms of how advanced the technology is.”

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Muscovite mica is commonly used in sample preparation for AFMs. Mica surfaces are used as clean imaging substrates, enabling the imaging of cell membranes and DNA molecules. This image shows an area of mica a whopping 8nm x 8nm in size. 

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Finally, here is an image of DNA on a mica surface. The image is 900nm x 900nm in size. To put that in context, a human chromsome is about 100nm in size.

(Our thanks to Professor Suzi Jarvis –leader of the Nanoscale Function Group’s multidisciplinary team of physcisists, engineers, and biologists– for kindly sharing some of her lab’s AFM images with MyScience.ie.)