Woman of the Week – Helen Free

For the next few months, we’ve decided to dig into the CR4 archives and expand upon some blog posts from 2007. Back then, we published a series of lists of women inventors and now we will write full blog posts about those who have yet to be featured. Do you know of a great person to be a subject? Let us know!

It’s hard to imagine a time when people with diabetes couldn’t monitor their glucose levels at home. But thanks to the inventiveness of Helen Free and her husband, Alfred, managing the disease is possible.

The invention, a dip-and-read stick coated in chemicals, can help a person see their levels by changing color when dipped into a urine or blood sample.

Helen Free (Murray) was born February 20, 1923. She went to school in Youngstown, Ohio. During her summers, she attended camp at the College of Wooster and had her sights set on going to college there. She intended to become a teacher, but when Pearl Harbor was bombed in 1941, many women were encouraged to study science because of the amount of young men drafted into the service.

Her first job was as a quality control chemist for Miles Laboratories, who created Alka Seltzer. But she really wanted to be a researcher. Alfred Free had a job open in his biochemistry group and she was offered the position.

At first, the team was researching antibiotics but soon moved onto dry reagent systems. They did research on Clinitest and Acetest, both tablets used to test glucose levels.

The group was tasked with further researching Clinitest and making it more sensitive. They also hoped to make testing easier for people instead of having to fumble around with test tubes and droppers.

They knew Clinitest detected the presence of all sugar but they wanted more specific results, like specifically identifying glucose. They embedded the reagents onto a filter paper strip and the result was a dip-and-read Clinistix. The process was very labor intensive – researchers had to cut the paper, dip it in the solution and dry it out – but it worked.

The test was easy enough for people to do at home and it served as inspiration for similar products that detect other diseases like Ictotest, which diagnoses Hepatitis A.

Clinastix were made available in 1956 and are still in use today. The couple continued to research on this discovery and in 1981, developed Multistix, a single strip urine analysis that can test for multiple things including ketones and other urinary tract disorders.

Both Helen and Alfred retired in 1982. Helen spent many years as a champion for science education. In 1993, she became the third of only seven women elected president of the American Chemical Society.

In 2000, the couple was inducted into the National Inventors Hall of Fame. In 2010, President Barack Obama awarded her the National Medal of Technology and Innovation.

The American Chemical Society also designated their work as a National Historic Chemical Landmark on May 1, 2010.