Helen Murray Free
First attending college with the intention of being an English and Latin teacher, Helen Murray Free was encouraged by her housemother to go into the sciences as the onset of World War II had taken many men from these fields.
Graduating with a degree in chemistry in 1945, she was hired at Miles Laboratories as a quality control chemist. Wanting to do research she interviewed to work in the lab of a new hire, Dr. Alfred Free. Not only did she join Dr. Free in his lab work, but a few years later the two would marry and spend the rest of their lives together working side by side.
Clinitest, previously developed at Miles Labs, was a tablet for testing the level of glucose in the urine of diabetes patients. The tablet, when placed in a test tube with a diluted urine solution, used a combination of chemicals that would react with a visible color change based on the amount of sugar present and the Free Research group was asked to improve the tablet’s sensitivity. Not settling for just improving the Clinitest, the group would develop other tablet based products first, Acetest, another product for diabetics followed by Icotest, a diagnostic tool for hepatitis A.
Wanting to move away from a tablet based test, the Frees worked together to develop the first urine test strip, a strip of paper coated with a chemical that turns color in the presence of a particular chemical substance in a urine sample. Their first product was Clinistix to test for glucose in urine but they quickly developed other strips for testing levels of other key diabetes indicators.
With that success they expanded yet again to combine more than one test on a single strip and by 1981 they had developed Multistix–a urinalysis strip that had ten different clinical tests on one strip.
Together Helen and Alfred Free had revolutionized diagnostic urine testing and in honor of this they were inducted into the National Inventors Hall of Fame in 2000 and eleven years later Helen was inducted into the National Women’s Hall of Fame.
Written by Angela Goad