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Helen M. Free

Chemist developed dip-and-read test strips that revolutionized glucose monitoring for people with diabetes

by Linda Wang
May 6, 2021


Photo of Helen M. Free.
Credit: Linda Wang/C&EN
Helen M. Free

Helen M. Free, who, along with her late husband Albert Free, helped revolutionize diabetes testing in the 1950s by developing “dip-and-read” test strips that detected levels of glucose in urine, died on May 1 in Elkhart, Indiana. She was 98.

“Helen was a superstar who made enormous contributions to the chemistry enterprise,” says Harry B. Gray, the Arnold O. Beckman Professor of Chemistry and the Founding Director of the Beckman Institute at the California Institute of Technology.

While at Miles Laboratories (now Bayer), the Frees developed Clinistix, reagent strips impregnated with two enzymes and a chromophore that, when dipped in urine, change color based on the concentration of glucose. This simple test gave people with diabetes a convenient way to monitor their glucose levels at home. The research led to dip-and-read test strips for the detection of other biomolecules, including those elevated in pregnancy. ACS honored the Frees’ work with a National Historic Chemical Landmark designation in 2010.

Free earned a BS in chemistry from the College of Wooster in 1944 and a master’s degree in health-care management from Central Michigan University in 1978. She was inducted into the National Inventors Hall of Fame in 2000. She received the National Medal of Technology and Innovation in 2009.

Throughout her career, Free was “an amazing role model for generations of young women—carrying out important research and raising a large, blended family,” says Madeleine Jacobs, former CEO of ACS, who has known Free since 1970. “She said she never felt discrimination—she simply forged ahead. She always had time for people. She was proud to be a chemist and was a wonderful ACS President. There are few women chemists in the world who have had the impact that Helen Free had.” Free served as ACS president in 1993; she was the third woman ever elected to this role.

Free was not only an inspiration to countless women in chemistry, she was also a champion of public outreach. In 1995, the ACS Committee on Public Relations and Communications established the Helen M. Free Award for Public Outreach, and Free became its first recipient.

Lydia Hines, the 2020 recipient of the award, says that Free was always generous with her time, “be it by traveling to a local section as a speaker or by participating in teacher-training events at the request of individual ACS members who shared her vision that chemistry is a discipline that can be grasped by individuals at any age.” Hines also recalls that Free often wore a bright red jacket, making her easy to spot in professional settings.

E. Gerald Meyer, emeritus professor of chemistry and former Dean of the College of Arts and Sciences at the University of Wyoming, recalls Free’s passion for connecting with the global chemistry community. “In the later part of her career Helen took a great interest in international science from both the standpoint of the work and the people,” he says “Her efforts created the current international affairs structure within the [American Chemical Society], which is a wonderful legacy.”

Other colleagues remember Free for her personal touch. ”She was a famous scientist but found time to do so many wonderful things,” says Madeleine M. Joullié, professor of chemistry at the University of Pennsylvania. “She was a role model for all women but what I miss most is her beautiful smile that she had every time you met her.”

Free is survived by six children, three stepchildren, 17 grandchildren, and 9 great-grandchildren.


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