When you need to see something so tiny that light skips right over it—and you don't want it vacuum-sealed and messed with in the way that a transmission electron microscope requires—you're in the market for a scanning electron microscope (SEM).
An SEM is the go-to machine for materials engineers, who are very interested in close-up pictures of faulty pipes or the inner workings of exotic, lab-created composites. That's why UAB's SEM is located on the ground floor of the School of Engineering. But the device is also gaining a following with researchers all over campus, says William Stonewall Monroe, director of the UAB Scanning Electron Microscope facility.
"If you want to look inside something, you use a transmission electron microscope," Monroe says. "That's what most people think of as an electron microscope. But the samples have to be elaborately prepared and able to survive the vacuum conditions."
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The SEM only shows the surface of an object, but its prep requirements are much more forgiving. And what it lacks in clarity—it can magnify objects up to 30,000 times, as opposed to the millions of times that a transmission electron microscope can achieve—it makes up in versatility. (There are several TEMs in the UAB High Resolution Imaging Facility.)
In its environmental mode, "we can put things that are still wet into this microscope," says Monroe. Researchers from the Department of Pathology are using the SEM to examine bone slices. A group in the Department of Physics is poring over its nanodiamonds in the device. And biologists are using it to look at how various processes affect cell growth. "They've been surprised by how much they can see," Monroe says.
Monroe spends his days at the Star Trek-style controls of the SEM, adjusting a range of dials and settings to bring out glorious details in a shattered pipe or sliver of sea urchin. Researchers often sit next to him while he works, observing the results on the lab's giant overhead flat-screen monitors. [The lab is so sleek it is a popular spot on campus tours.] The images he acquires help advance research; they also help it attract attention. "A picture really helps your case if you are publishing," Monroe observes.
Because the SEM lab is open to any investigator on campus, "I get to see research from all over," Monroe says. "It's a fascinating job."