Gaze at worlds too small to see with the naked eye
By Robin A. Smith
The sewer gnat is a common nuisance around kitchen and bathroom drains that’s no bigger than a pea. But magnified thousands of times, its compound eyes and bushy antennae resemble a first place winner in a Movember mustache contest.
Sewer gnats’ larger cousins, horseflies are known for their painful bite. Zoom in and it’s easy to see how they hold onto their furry livestock prey: the tiny hooked hairs on their feet look like Velcro.
Students in professor Fred Nijhout’s entomology class photograph these and other specimens at more than 300,000 times magnification at Duke’s Shared Materials Instrumentation Facility (SMIF) administered through the Pratt School of Engineering.
There the insects are dried, coated in gold and palladium, and then bombarded with a beam of electrons from a scanning electron microscope, which can resolve structures tens of thousands of times smaller than the width of a human hair.
From a ladybug’s leg to a weevil’s suit of armor, the bristly, bumpy, pitted surfaces of insects are surprisingly beautiful when viewed up close.
"The students have come to treat travels across the surface of an insect as the exploration of a different planet," Nijhout said.
You, too, can gaze at alien worlds too small to see with the naked eye. Students and instructors across campus can use the SMIF’s high-powered microscopes and other state of the art research equipment at no charge with support from the Class-Based Explorations Program.
Biologist Eric Spana’s experimental genetics class uses the microscopes to study fruit flies that carry genetic mutations that alter the shape of their wings.
Students in professor Hadley Cocks’ mechanical engineering 415L class take lessons from objects that break. A scanning electron micrograph of a cracked cymbal once used by the Duke pep band reveals grooves and ridges consistent with the wear and tear from repeated banging.
These students are among more than 200 undergraduates in eight classes who benefitted from the program last year, thanks to a grant from the Donald Alstadt Foundation.
You don’t have to be a scientist, either. Historians and art conservators have used scanning electron microscopes to study the surfaces of Bronze Age pottery, the composition of ancient paints and even dust from Egyptian mummies and the Shroud of Turin.
Instructors and undergraduates are invited to find out how they could use the microscopes and other nanotech equipment in the SMIF in their teaching and research. Queries should be directed to Dr. Mark Walters, Director of SMIF, via email at email@example.com.
Located on Duke’s West Campus in the Fitzpatrick Building, the SMIF is a shared use facility available to Duke researchers and educators as well as external users from other universities, government laboratories or industry through a partnership called the Research Triangle Nanotechnology Network. For more info visit http://smif.pratt.duke.edu/.