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[Obituary] Helen Mae Murray Free

Chemist and co-inventor of dip-and-read diagnostic testing. She was born on Feb 20, 1923, in Pittsburgh, PA, USA, and died following a stroke in Elkhart, IN, USA, on May 1, 2021, aged 98 years.

In the early 1940s, testing for the presence and amount of glucose in urine was cumbersome and inaccurate. “It was wet chemistry”, says William Carroll, Jr, a former President of the American Chemical Society (ACS) and now, after his retirement from industry, an adjunct professor of chemistry at the Indiana University Bloomington, USA. “If you wanted to know how much glucose there was in urine, there were reagents you'd add, boil it up, and look for a colour change.” In the following decade, Helen Free and her husband-to-be Alfred (Al) Free, working at the Miles Laboratories in Elkhart, IN, USA, not only simplified testing for diabetes, but also began a revolution in the techniques of diagnostic chemistry. Her innovations established Free's reputation and she later used it to encourage a wider public interest in chemistry, especially among women and girls.

Science had not been on the young Free's agenda when she began contemplating a career. Her preference was for teaching English or Latin, and she enrolled at Ohio's liberal arts College of Wooster in 1941. With the advent of World War 2, much began to change for women. “It was an era of opportunity for professional women because a lot of the men were otherwise occupied”, says Carroll. Free was encouraged to switch to chemistry, did so, and enjoyed it. As she was later to reflect, “I think that was the most terrific thing that ever happened because I certainly wouldn't have done the things that I've done in my lifetime.”

Free graduated in 1944. Her first job offer was less than inspiring: the routine testing of creosote for sale to farmers. A more enticing offer came from Miles Laboratories, a company later to become part of Bayer. She joined it as a quality control chemist; 2 years later she was promoted to the role of research chemist in the biochemistry section of its Miles-Ames Research Laboratory. She stayed with the company until her retirement in 1982, by which time she was its Director of Marketing Services for the Research Products Division.

Free's big opportunity had come in 1946 when the newly appointed head of biochemistry, Al Free, recruited her to work with him on improving the company's test for glucose. This had already been simplified, and now comprised a tablet in a test tube to which urine was added using a dropper. Al and Helen aimed to go a step further, says Carroll. “What if we could just dip a strip of sensitised paper into the urine, they wondered, and use that colour change as an indicator? It was a brilliant insight…but [developing] the technology for actually making a strip was more daunting than having the insight.” Yet they succeeded, and 1956 saw the company launching its dip-and-read Clinistix. “Having something so simple and easy to use was really game-changing”, says Carolyn Ribes, a business analytical leader for Dow in Terneuzen, Netherlands, who first met Free through her work for the ACS. And as Carroll points out, “It took a lot less time and made it easier for physicians to do their own testing. It was more accurate, and served patients much better.” The Frees, who married in 1947, went on to devise tests for, among other things, ketones, bilirubin, protein, and nitrite. They also devised reagent strips for testing glucose in blood. Al Free died in 2000 but Helen maintained her involvement in chemistry, and in 2010 received the National Medal of Technology and Innovation.

“Helen brought great enthusiasm and energy to everything”, says Ribes. “She had a lot of drive. She was very optimistic, always convinced that she was going to find a way [of getting things done].” Carroll agrees: “Helen was an enormously practical person, and a strong advocate for chemistry.” As Ribes explains, Free, who was elected ACS President in 1993, began to take on an ambassadorial role for her subject. “She had a great enthusiasm for outreach, helping people understand the role of chemistry in everyday life…and encouraging children to study science, technology, engineering, and maths.” In 1995, the ACS presented her with an award for public outreach. Still made annually, the award is now named after her. A fitting tribute to someone who, as Carroll says, was “absolutely evangelical about chemistry”. Free is survived by her daughters, Bonnie, Nina, and Penny, and sons, Eric, Kurt, and Jake.

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Helen Mae Murray Free

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