The innovation and litigation behind biology’s most ubiquitous tool.

This essay has been cross-posted from Asimov Press, a publishing venture devoted to biotechnology.

I. “Hazards of Mouth Pipetting”

The micropipette, an instrument favored by researchers around the world to measure and move liquids from one container to another and used for everything from forensic analysis to DNA sequencing, was invented by an obscure, 32-year-old German postdoc after a particularly productive two-day tantrum.

Heinrich Schnitger was born in Lemgo, Germany in 1925. He fought in the Second World War, but was hospitalized with tuberculosis and removed from active duty as a result. The illness probably saved his life. After the war, Schnitger earned a PhD in medicine and began a research position at the University of Marburg.

There, Schnitger busied himself with chromatography, a technique to isolate molecules by flowing liquids through columns and then painstakingly sorting the tiny drops that emerged. At the time, these experiments were done entirely with mouth pipettes. Researchers would suck liquids into a glass tube and then transfer the liquid to another container. But mouth pipettes were fragile, inaccurate, and dangerous.

Dr. Adah Elizabeth Verder using a mouth pipette, ca. 1938. Credit: National Institutes of Health

A 1915 survey of 57 research laboratories found that 40 percent of workplace-related infections were directly linked to mouth pipetting. Decades later, in the 1960s, U.S. Army researchers penned an article entitled, “Hazards of Mouth Pipetting.” Leaving no room for ambiguity, they conclude in all caps: DO NOT MOUTH PIPETTE INFECTIOUS OR TOXIC FLUIDS and USE A PIPETTOR DEVICE FOR PIPETTING.1

Schnitger viewed mouth pipettes with “great contempt.” In 1957, presumably driven by this pique, he vanished from the laboratory and returned, two days later, “with a self-designed tool to pipette microlitre volumes.” On May 3rd, Schnitger filed a patent entitled, “Device for quick and precise pipetting of small amounts of liquid.” The patent was granted in 1961, and his design had “all the essential features of the modern pipette,” according to a close witness of the invention, including a spring-loaded piston, second spring to shoot out residual liquid, and plastic tip.2

It is nearly impossible to imagine modern biology without the micropipette, which has enabled scientists to ...

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