A new form of electron microscopy allows researchers to examine nano-scale tubular materials while they are “alive” and forming liquids—a first in the field.
Developed by a multidisciplinary team at the University of Tennessee, Knoxville, and Northwestern University, the new technique, called variable temperature liquid-phase transmission electron microscopy (VT-LPTEM), allows researchers to investigate these dynamic, sensitive materials with high resolution. With this information, researchers can better understand how nano-materials grow, form, and evolve.
The study was co-led by David Jenkins, UT associate professor of chemistry, and Northwestern’s Nathan Gianneschi, the Jacob and Rosaline Cohn Professor of Chemistry.
“Until now, we could only look at ‘dead,’ static materials,” said Gianneschi. “This new technique allows us to examine dynamics directly—something that could not be done before.”
The paper was published online in the Journal of the American Chemical Society.
After live-cell imaging became possible in the early 20th century, it revolutionized the field of biology. For the first time, scientists could watch living cells as they actively developed, migrated, and performed vital functions. Before, researchers could only study dead, fixed cells. The technological leap provided critical insight into the nature and behavior of cells and tissues.
“We think LPTEM could do for nano-science what live-cell light microscopy has done for biology,” Gianneschi said.
LPTEM allows researchers to mix components and perform chemical reactions while watching them unfold beneath a transmission electron microscope.
The team studied metal-organic nano-tubes (MONTs). A subclass of metal-organic frameworks, Jenkins said MONTs “have been postulated to be effective as nano-straws or nano-wires, which could have practical applications in nano-medicine or nano-electronics.”
Possible applications for MONTs as nano-wires include miniature electronic devices, nano-scale lasers, semiconductors, and sensors for detecting cancer bio-markers and virus particles. MONTs, however, are little explored because the key to unlocking their potential lies in understanding how they are formed.
For the first time, the UT–Northwestern team watched MONTs form with LPTEM and made the first measurements of finite bundles of MONTs on the nano-meter scale.
The research was a collaboration between Jenkins’s laboratory, which has expertise in metal-organic nano-tubes, and Gianneschi’s laboratory, which has expertise in transmission electron microscopy. UT graduate student Kristina Vailonis and Northwestern postdoctoral fellow Karthikeyan Gnanasekaran served as the paper’s co-first authors.
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Contact:
Andrea Schneibel (andrea.schneibel@utk.edu, 865-974-3993)
Amanda Morris (amandamo@northwestern.edu, 847-467-6790)