Research from the laboratory of Matthew Lev at Washington University in St. Louis offers entirely new ways to see the little one.
The research – two papers written by PhD students at the McKelvey School of Engineering – has been published in the journals Optical and Nano-letters.
They have developed new hardware and algorithms that allow them to visualize the building blocks of the biological world beyond three dimensions in ways that until now have not been feasible. After all, cells are 3D objects and full of “things” – molecules – that move, twist, turn and tumble to drive life itself.
Like traditional microscopes, the work of two Lew Lab PhD students, Tingting Wu and Oumeng Zhang, uses light to peer into the microscopic world – but their innovations are anything but traditional. Currently, when people use light in imagery, they are probably interested in the brightness of that light or its color. But light has other properties, including polarization.
“Oumeng’s work distorts the polarization of light,” said Lew, assistant professor in the Department of Electrical and Systems Engineering at Preston M. Green. “That way you can see both how things translate (move in straight lines) and rotate at the same time” – something traditional imagery doesn’t.
“The development of new technologies and the ability to see things we couldn’t see before is exciting,” Zhang said. This unique ability to track both rotation and position gives it unique insight into how biological materials – human cells and pathogens, for example – interact.
Wu’s research also provides a new way to image cell membranes and, in a way, see inside them. Using fluorescent tracer molecules, she maps how tracers interact with fat and cholesterol molecules in the membrane, determining how lipids are arranged and organized.
“Any cell membrane, any nucleus, anything inside the cell is a 3D structure,” she said. “It helps us probe the full picture of a biological system. This allows us, for any biological sample, to see beyond three dimensions – we see 3D structure plus three dimensions of molecular orientation, giving us 6D images.
Researchers have developed computer imaging technology, which combines software and hardware, to successfully see what was previously invisible.
“That’s part of the innovation,” Lew said. “Traditionally, bioimaging labs were tied to whatever commercial manufacturers made. But if we think of things differently, we can do so much more.
This research was supported by the National Science Foundation, No. ECCS-1653777 and the National Institute of General Medical Sciences, No. R35GM124858.
The McKelvey School of Engineering at Washington University in St. Louis promotes independent research and education with an emphasis on scientific excellence, innovation, and collaboration without boundaries. McKelvey Engineering offers some of the best research and graduate programs in all departments, especially in biomedical engineering, environmental engineering, and computer science, and offers one of the most selective undergraduate programs in the country. With 140 full-time faculty, 1,387 undergraduate students, 1,448 graduate students, and 21,000 living alumni, we work to solve some of society’s greatest challenges; prepare students to become leaders and innovate throughout their careers; and to be a catalyst for economic development for the Saint-Louis region and beyond.
