Just the name of a remarkable new piece of equipment in chemistry researcher Rob Schurko’s lab is probably enough to pique the curiosity of the most casual observers of all things scientific: the ultra-fast magic-angle spinning probe.
“It’s amazing what you can do with this thing,” says Dr. Schurko. “The physics and engineering of it is just beautiful.”
One of only four in Canada, the probe is an analytical piece of equipment used to better understand the molecular structure of solid materials. Used in conjunction with the nuclear magnetic resonance (NMR) spectrometer in Schurko’s Essex Hall lab, it will be primarily for characterizing materials to help pharmaceutical companies make more effective medicines.
“The number one application for this will be to look at solid pharmaceutical compounds,” Schurko said.
The way molecules in solid pharmaceutical products are aligned with one another can affect everything from how long they last on a store shelf to how well they perform in your body, Schurko said. When drug companies make new products, they combine molecules from certain chemical materials and monitor how they interact. The ultra-fast magic angle spinning probe provides an efficient means of fingerprinting and identifying these forms, which are known as polymorphs.
In a nutshell, here’s how it works: samples of materials smaller than a grain of rice are placed in a tiny ceramic holder that’s inserted in the top of the stainless steel cylindrical probe. It’s then placed inside the NMR superconducting magnet, which is housed in a large tank and has an enormous magnetic field. The ceramic holder is oriented at the “magic” angle of 54.74 degrees with respect to that magnetic field. Gas jets force the sample to spin at an incredible 3.9 million revolutions per minute, or 65,000 revolutions per second. A coil wound around the sample holder blasts it with radio frequency fields, which generates a graph or “spectrum” that scientists can read to determine, among other things, the positioning of molecules in solid compounds such as drugs.
Most NMR experiments are done on liquid samples, in which molecules move about very rapidly, providing clearly defined “NMR spectra” which can be analyzed to predict molecular structure. That’s not the case with solids where molecules are stationary and important structural information is lost. However the rapid spinning of the ultra-fast magic-angle spinning probe mimics the motional process of the molecules resulting in high quality spectra similar to those found in liquids.
“This is going to open up a lot of doors in terms of the materials we can investigate,” Schurko said of the device. “Until recently, you had to use very cumbersome techniques to run these experiments that don’t always work out.”
Karen Johnston and Chris Harris, post-doctoral fellows in Schurko’s lab, are both very excited about the chance to work with the new equipment, which was bought from the German company Bruker BioSpin and paid for with a $111,000 grant from the Natural Sciences and Engineering Research Council.
“Just the engineering that goes in to making something like this is amazing,” said Harris, who originally hails from Edmonton. “It really changes what you’re capable of doing and puts you in a whole new experimental regime.”