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Development of Diagnostic Test Strips

Location: Elkhart, IN, USA
Date: 1941
Creator(s): Free, Al, Free, Helen

It is difficult to recall a time when doctors and patients had trouble tracking the presence of glucose and other substances in urine and blood. Lack of sufficient measurement tools made it difficult to manage a host of diseases, including diabetes as well as other metabolic diseases and kidney and liver conditions. Today, self-management of these diseases is an easier process because of the development of diagnostic test strips by Alfred and Helen Free and their research team at Miles Laboratories.


The text of the plaque commemorating the development reads:

A Miles Laboratories research team led by Alfred and Helen Free developed the first diagnostic test strip, Clinistix®, for detecting glucose in urine. Reagent-impregnated strips changed color based on the concentration of glucose. This breakthrough led to additional dip-and-read tests for proteins and other substances. Subsequently, researchers devised a method to combine several tests on one strip to provide healthcare professionals with simple, immediate tools to aid in the detection of disease. These innovations, along with instrument-based measurement of glucose in fingertip blood, provided patients with inexpensive means to aid in the management of diabetes and kidney disease, significantly improving their quality of life.

Era: 1940s
Innovation designated by:
Development of Diagnostic Test Strips
Advert for Ames home urine testing kit
ETHOS Science Center
1025 N Michigan St
Elkhart, IN, USA

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