Biochemist and crystallographer Nadrian “Ned” Seeman died in New York City at the age of 75 on November 16. Seeman is best known for inventing self-assembling DNA structures, which launched the field of DNA nanotechnology.
Born in Chicago in 1945, Seeman was an only child whose father was a salesman and whose mother took a hiatus from teaching elementary school to take care of her own mother, who lived with them. Nature reports that Seeman developed a love of science because of his high school biology teacher. He studied biochemistry at the University of Chicago, graduating in 1966.
Seeman stayed in Chicago as he started graduate school, but then transferred to his mother’s hometown to attend the University of Pittsburgh, where he graduated with a PhD in crystallography in 1970. His first postdoc was a two-year stint at Columbia University. That was followed by five years at MIT in the lab of legendary molecular biologist Alexander Rich.
Seeman started his first lab at SUNY's Albany campus in 1977. In an autobiographical essay, he minced no words in calling that position a “scientific death sentence,” even though he did make significant strides during that time. At the request of a colleague in 1978, Seeman used synthetic DNA to build a model of a Holliday junction, an intersection of four strands of double-stranded DNA. That was the start of the field of DNA nanotechnology, which exploits the properties of nucleic acid binding to create shapes that may not appear in nature.
He began thinking about whether it could be possible to make more complex branched junctions, and an idea came to him in 1980, Seeman told The Scientist in a 2011 profile. “One day I went over to the pub to think about what six-armed junctions might look like when I realized that they’d be just like the flying fish in [artist M.C.] Escher’s woodcut Depth. The fish have heads and tails, top and bottom fins, and left and right fins. And they’re arranged like the molecules in a crystal.”
This type of design allowed Seeman to make crystalline structures out of molecules notoriously difficult to capture via x-ray crystallography. He learned how to synthesize DNA strands himself and eventually figured out how to make them self-assemble using sticky ends, bypassing the trial-and-error—or, as he called it, “piss-in-a-pot-and-pray”—experiments usually required for crystallization. “I don’t have the patience for it,” Seeman told The Scientist, “and I’m not quite enough of a jerk to force my students to do that kind of experiment for me.”
In 1988, Seeman moved downstate for a role in NYU’s chemistry department, where he remained until his death. His first graduate students at NYU built rigid motifs of DNA that set the stage for the creation of DNA nanomechanical devices—and perhaps, someday, nanocomputers.
Seeman rejoiced when DNA nanotechnology caught on and dozens of other labs began doing similar work. “We don’t have to have all the ideas anymore, and we don’t have to make all the mistakes,” he wrote in his autobiography.
Seeman’s work was recognized with many accolades throughout his career, including the 2010 Kavli Prize in neuroscience, which he shared with Donald Eigler “for their development of unprecedented methods to control matter on the nanoscale.”
According to his obituary on Legacy.com, Seeman met his wife, Barbara Lipski, at his 50th high school reunion. He is survived by Lipski and his “scientific children” around the world.
“I’m expecting to be carried feet first out of my office one day,” Seeman told The Scientist a decade ago. “Why would I ever want to retire? This is too much fun.”