High-tech microscope yields beautiful scientific images
By Colleen MacPherson
It has the impressive-sounding title of Atomic Force Microscope (AFM), and one University professor describes it as “the world’s smallest record player”, but instead of producing beautiful music, this unique piece of equipment produces beautiful images.
Matthew Paige, assistant professor of chemistry, explained that the AFM allows for a close-up look at the surface of various materials, mapping what he calls “the lumps and bumps” that are otherwise invisible to the human eye. Those lumps could be atoms (thus the ‘atomic’ in the microscope name) or much larger features, with the colours in the images reflecting the various heights and depths of the surface. Being able to view the surface features of a material makes the AFM an important tool for, among other things, understanding the characteristics of both new and existing materials or for quality control, he said.
The AFM consists of an insulated box, about the size of a microwave oven on its side, a suspended platform to limit vibration, and a removable cylindrical apparatus that holds the ‘turntable’ – a metal disk. Paige explained the AFM can be used to examine “anything you can pin down or glue to the turntable within certain height limitation”. The ‘tone arm’ is fitted with a microscopic ‘stylus’ that then scrapes over the material, creating an image by measuring the forces between the surface and the tip (this is where ‘force’ comes from in the AFM’s name).
Paige said one particularly valuable aspect of the AFM is its ability to create images under liquid. This allows researchers to study, for example, “proteins that are doing something in a living organism”. The AFM can produce time-lapse images of the protein at work “but at an atomic level”.
As if that’s not impressive enough, Paige is working to create an even more versatile tool. He is attempting to expand the AFM’s capability to include extracting chemical information from samples.